Companhia de Saneamento Básico do Estado de São Paulo - SABESP (SBS) 20-F 27 Apr 22 2021 FY Annual report (foreign) Financial data

Cover

Cover	12 Months Ended
	Dec. 31, 2021shares
Cover [Abstract]
Document Type	20-F
Amendment Flag	false
Document Registration Statement	false
Document Annual Report	true
Document Transition Report	false
Document Shell Company Report	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2021
Current Fiscal Year End Date	--12-31
Entity File Number	001-31317
Entity Registrant Name	COMPANHIA DE SANEAMENTO BASICO DO ESTADO DE SAO PAULO-SABESP
Entity Central Index Key	0001170858
Entity Address, Address Line One	Rua Costa Carvalho, 300
Entity Address, City or Town	São Paulo
Entity Address, Country	BR
Entity Address, Postal Zip Code	05429-900
City Area Code	+55 11
Local Phone Number	3388 8247
Title of 12(b) Security	American Depositary Shares
Trading Symbol	SBS
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Document Accounting Standard	International Financial Reporting Standards
Entity Shell Company	false
Entity Common Stock, Shares Outstanding	683,509,869
Contact Personnel Name	Osvaldo Garcia
Contact Personnel Email Address	osvaldogarcia@sabesp.com.br
ICFR Auditor Attestation Flag	true
Auditor Name	KPMG Auditores Independentes
Auditor Location	São Paulo, SP, Brasil
Auditor Firm ID	1124

Statement of Financial Position

Statement of Financial Position - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current
Cash and cash equivalents	R$ 717929	R$ 396401
Financial investments	2,433,385	3,411,146
Trade receivables	2,695,077	2,204,029
Accounts receivable from related parties	173,657	168,054
Inventories	113,506	104,848
Restricted cash	28,467	35,742
Recoverable taxes	276,104	22,672
Other assets	64,873	97,946
Total current assets	6,502,998	6,440,838
Noncurrent
Trade receivables	223,234	246,957
Accounts receivable from related parties	644,895	638,591
Escrow deposits	141,667	164,942
Water and Basic Sanitation National Agency – ANA	20,666	26,463
Other assets	161,369	148,164
Investments	79,437	63,417
Investment properties	46,126	46,274
Contract assets	8,550,102	7,969,164
Intangible assets	36,503,834	34,405,575
Property, plant and equipment	291,157	268,251
Total noncurrent assets	46,662,487	43,977,798
Total assets	53,165,485	50,418,636
Current
Trade payables and contractors	236,763	263,741
Borrowings and financing	1,830,617	3,034,449
Labor and social obligations	426,616	410,943
Taxes and contributions	257,130	266,819
Interest on capital	548,006	231,611
Provisions	809,821	760,209
Services payable	469,027	453,750
Public-Private Partnership - PPP	142,757	130,207
Program Contract Commitments	77,652	162,541
Other liabilities	294,538	185,860
Total current liabilities	5,092,927	5,900,130
Noncurrent
Borrowings and financing	15,893,219	14,224,175
Deferred income tax and social contribution	283,739	320,716
Deferred Cofins and PASEP	159,456	149,444
Provisions	638,672	492,093
Pension plan obligations	2,321,662	2,868,594
Public-Private Partnership - PPP	2,917,428	3,045,066
Program Contract Commitments	44,995	68,939
Other liabilities	881,528	555,775
Total noncurrent liabilities	23,140,699	21,724,802
Total liabilities	28,233,626	27,624,932
Equity
Capital stock	15,000,000	15,000,000
Earnings reserves	9,885,485	8,194,706
Other comprehensive loss	46,374	(401,002)
Total equity	24,931,859	22,793,704
Total equity and liabilities	R$ 53165485	R$ 50418636

Income Statements

Income Statements R$ in Thousands	12 Months Ended
	Dec. 31, 2021$ / shares	Dec. 31, 2021BRL (R$)	Dec. 31, 2020$ / shares	Dec. 31, 2020BRL (R$)	Dec. 31, 2019$ / shares	Dec. 31, 2019BRL (R$)
Profit or loss [abstract]
Net operating revenue		R$ 19491061		R$ 17797541		R$ 17983654
Operating costs		(12,800,042)		(11,179,667)		(10,137,637)
Gross profit		6,691,019		6,617,874		7,846,017
Selling expenses		(825,879)		(751,286)		(803,404)
Allowance for doubtful accounts		(643,730)		(444,826)		(128,099)
Administrative expenses		(1,124,069)		(1,051,181)		(1,187,844)
Other operating income (expenses), net		(21,841)		107,656		(18,748)
Equity results of investments in affiliaties		22,079		14,136		3,701
Profit from operations before finance income (expenses) and income tax and social contribution		4,097,579		4,492,373		5,711,623
Financial expenses		(1,448,295)		(1,324,759)		(1,173,425)
Financial revenues		472,408		336,731		372,842
Exchange result, net		48,464		(2,178,343)		(233,098)
Financial result, net		(927,423)		(3,166,371)		(1,033,681)
Profit before income tax and social contribution		3,170,156		1,326,002		4,677,942
Income tax and social contribution
Current		(961,556)		(460,721)		(1,155,463)
Deferred		97,269		108,037		(154,962)
Income tax and social contribution		(864,287)		(352,684)		(1,310,425)
Profit for the year		R$ 2305869		R$ 973318		R$ 3367517
Earnings per share – basic and diluted (in reais) | $ / shares	$ 3.37		$ 1.42		$ 4.93

Statements of Comprehensive Inc

Statements of Comprehensive Income - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Profit or loss [abstract]
Profit for the year	R$ 2305869	R$ 973318	R$ 3367517
Other comprehensive income (loss)	447,376	511,169	(363,076)
Items which will not be subsequently reclassified to the income statement:
Actuarial gains and (losses) on defined benefit Plans, net of income tax	447,376	511,152	(363,059)
Other		17	(17)
Total comprehensive income for the year	R$ 2753245	R$ 1484487	R$ 3004441

Statements of Changes in Equity

Statements of Changes in Equity - BRL (R$) R$ in Thousands	Issued capital [member]	Statutory reserve [member]	Investment Reserve [Member]	Additional Dividend Proposed [Member]	Retained earnings [member]	Accumulated other comprehensive income [member]	Total
Beginning balance, value at Dec. 31, 2018	R$ 15000000	R$ 1200030	R$ 3840422	R$ 60331		R$ 549095	R$ 19551688
IfrsStatementLineItems [Line Items]
Net income for the year					3,367,517		3,367,517
Actuarial gains (losses)						(363,076)	(363,076)
Total comprehensive income for the year					3,367,517	(363,076)	3,004,441
Legal Reserve		168,376			(168,376)
Interest on shareholder's equity (R$0.80122 per share)					(799,785)		(799,785)
2020 additional proposed dividends, approved (R$0.03859 per share)				(60,331)			(60,331)
Additional proposed dividends (R$ 0.14148 per share)				141,203	(141,203)
Withholding income tax on interest on capital attributable as minimum mandatory dividends				(60,230)			(60,230)
Transfer to investments reserve			2,258,153		(2,258,153)
Ending balance, value at Dec. 31, 2019	15,000,000	1,368,406	6,098,575	80,973		(912,171)	21,635,783
IfrsStatementLineItems [Line Items]
Net income for the year					973,318		973,318
Actuarial gains (losses)						511,169	511,169
Total comprehensive income for the year					973,318	511,169	1,484,487
Legal Reserve		48,666			(48,666)
Interest on shareholder's equity (R$0.80122 per share)					(231,163)		(231,163)
2020 additional proposed dividends, approved (R$0.03859 per share)				(80,973)			(80,973)
Additional proposed dividends (R$ 0.14148 per share)				40,806	(40,806)
Withholding income tax on interest on capital attributable as minimum mandatory dividends				(14,430)			(14,430)
Transfer to investments reserve			652,683		(652,683)
Ending balance, value at Dec. 31, 2020	15,000,000	1,417,072	6,751,258	26,376		(401,002)	22,793,704
IfrsStatementLineItems [Line Items]
Net income for the year					2,305,869		2,305,869
Actuarial gains (losses)						447,376	447,376
Total comprehensive income for the year					2,305,869	447,376	2,753,245
Legal Reserve		115,293			(115,293)
Interest on shareholder's equity (R$0.80122 per share)					(547,645)		(547,645)
2020 additional proposed dividends, approved (R$0.03859 per share)				(26,376)			(26,376)
Additional proposed dividends (R$ 0.14148 per share)				96,700	(96,700)
Withholding income tax on interest on capital attributable as minimum mandatory dividends				(41,069)			(41,069)
Transfer to investments reserve			1,546,231		(1,546,231)
Ending balance, value at Dec. 31, 2021	R$ 15000000	R$ 1532365	R$ 8297489	R$ 55631		R$ 46374	R$ 24931859

Statements of Changes in Equi_2

Statements of Changes in Equity (Parenthetical) - R$ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of changes in equity [abstract]
Interest on shareholder's equity	R$ 0.80122	R$ 0.33820	R$ 1.17012
Additional proposed dividends, approved	0.03859	0.11847	R$ 0.08827
Additional proposed dividends, per share	R$ 0.14148	R$ 0.05970

Statements of Cash Flows

Statements of Cash Flows - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flow from operating activities
Profit before income tax and social contribution	R$ 3170156	R$ 1326002	R$ 4677942
Adjustments for:
Depreciation and amortization	2,253,322	2,037,112	1,780,094
Residual value of property, plant and equipment, intangible assets and investment properties written-off	27,754	16,590	45,434
Bad debt expense	643,730	444,826	128,099
Agreement signed with the municipality of Mauá		(280,774)
Agreement signed with the municipality of Santo André			(1,336,908)
Provisions and inflation adjustment	380,624	444,090	384,620
Interest calculated on borrowings and financing payable	647,980	559,931	568,679
Inflation adjustment and exchange gains (losses) on borrowings and financing	177,269	2,267,179	280,526
Interest and inflation adjustment on liabilities	37,202	20,931	46,038
Interest and inflation adjustment on assets	(171,173)	(46,946)	(39,547)
Finance charges from customers	(349,491)	(344,513)	(364,291)
Construction margin on intangible assets arising from concession agreements	(98,402)	(86,477)	(65,172)
Provision for Consent Decree (TAC) and Knowledge Retention Program (PRC)	3,195	1,684	(130,345)
Equity results of investments in affiliaties	(22,079)	(14,136)	(3,701)
Interest and monetary restatement (PPP)	464,398	424,639	397,576
Provision from São Paulo agreement	131,878	142,232	135,013
Pension plan obligations	176,673	136,585	267,423
Other adjustments	15,152	5,283	5,863
	7,488,188	7,054,238	6,777,343
Changes in assets
Trade receivables	(742,260)	(213,084)	(72,538)
Accounts receivable from related parties	20,665	83,419	26,358
Inventories	(8,658)	(34,394)	(4,858)
Recoverable taxes	(253,432)	(342,127)	239,437
Escrow deposits	43,865	35,630	(12,302)
Other receivables	31,386	(36,264)	(1,966)
Changes in liabilities
Trade payables and contractors	(245,501)	(248,404)	(349,037)
Services payable	(116,601)	(162,560)	(114,957)
Accrued payroll and related taxes	12,478	(185,020)	159,794
Taxes and contributions	196,255	384,676	63,276
Deferred Cofins/PASEP	10,012	5,751	2,863
Provisions	(184,433)	(227,596)	(241,674)
Pension obligations	(215,937)	(123,014)	(221,784)
Other liabilities	(68,260)	(13,306)	(92,637)
Cash generated from operations	5,967,767	5,977,945	6,157,318
Interest paid	(845,445)	(626,625)	(737,326)
Income tax and social contribution paid	(1,208,569)	(373,112)	(1,222,747)
Net cash generated from operating activities	3,913,753	4,978,208	4,197,245
Cash flows from investing activities
Acquisition of contract assets and intangible assets	(3,696,669)	(3,299,657)	(3,195,247)
Restricted cash	7,275	(9,724)	5,882
Financial investments	1,076,468	(3,411,146)
Investment increase/(decrease)		(5,734)	240
Purchase of property, plant and equipment	(50,281)	(42,407)	(78,159)
Net cash used in investing activities	(2,663,207)	(6,768,668)	(3,267,284)
Borrowings and financing
Proceeds from loans	2,922,811	4,777,474	1,793,388
Payment of loans	(2,896,604)	(3,244,099)	(2,148,198)
Payment of interest on capital	(254,218)	(890,095)	(739,996)
Public-Private Partnership - PPP	(579,486)	(543,346)	(548,079)
Program Contract Commitments	(121,521)	(166,283)	(63,057)
Net cash used in financing activities	(929,018)	(66,349)	(1,705,942)
Increase / (decrease) in cash and cash equivalents	321,528	(1,856,809)	(775,981)
Represented by:
Cash and cash equivalents at the beginning of the year	396,401	2,253,210	3,029,191
Cash and cash equivalents at the end of the year	R$ 717929	R$ 396401	R$ 2253210

Operations

Operations	12 Months Ended
	Dec. 31, 2021
Operations
Operations	1 Operations Companhia de Saneamento Básico do Estado de São Paulo ("SABESP" or "Company") is a mixed-capital company headquartered in São Paulo, at Rua Costa Carvalho, 300, CEP 05429-900, controlled by the State of São Paulo. The Company is engaged in the provision of basic and environmental sanitation services in the State of São Paulo, as well as it supplies treated water and sewage services on a wholesale basis. In addition to providing basic sanitation services in the State of São Paulo, SABESP may performs these activities in other states and countries, and can operate in drainage, urban cleaning, solid waste handling and energy markets. SABESP aims to be a world reference in the provision of sanitation services, in a sustainable, competitive and innovative manner, with a focus on customers. As of December 31, 2021, the Company operated water and sewage services in 375 municipalities of the State of São Paulo, 342 have already signed contracts, pursuant to Law 11,445/2007. Most of these municipalities’ operations are based on 30-year concession, program and services contracts, except for the municipalities of Guarulhos, Mauá, Santo André, São Bernardo do Campo, São João da Boa Vista and Tejupá, which have a 40-year term. The table below shows a summary of the contractual situation of the municipalities served: December 31, 2021 December 31, 2020 Total municipalities that have already signed contracts 342 342 Balance – intangible and contract assets 42,260,091 39,440,568 Percentage of intangible and contract assets 93.80% 93.08% Revenue from sanitation services (excluding construction revenue) 15,490,808 14,406,803 Percentage of revenue from sanitation services (excluding construction revenue) 95.01% 95.05% Municipalities with expired contracts: 8 8 Balance – intangible and contract assets 214,329 264,931 Percentage of intangible and contract assets 0.48% 0.63% Revenue from sanitation services (excluding construction revenue) 41,194 39,088 Percentage of revenue from sanitation services (excluding construction revenue) 0.25% 0.26% Municipalities with concession agreements due by 2030: 25 25 Balance – intangible and contract assets 1,127,920 1,436,529 Percentage of intangible and contract assets 2.50% 3.39% Revenue from sanitation services (excluding construction revenue) 653,408 597,483 Percentage of revenue from sanitation services (excluding construction revenue) 4.01% 3.94% Municipality of São Paulo: Percentage of intangible and contract assets 43.11% 37.94% Percentage of revenue from sanitation services (excluding construction revenue) 44.45% 44.58% The Company's shares have been listed in the “Novo Mercado” (New Market) segment of B3 under the ticker symbol SBSP3 since April 2002 and on the New York Stock Exchange (NYSE) as American Depositary Receipts (“ADRs”) Level III, under the SBS code, since May 2002. Since 2008, the Company has been setting up partnerships with other companies, which resulted in the following companies: Sesamm, Águas de Andradina, Saneaqua Mairinque, Aquapolo Ambiental, Águas de Castilho, Attend Ambiental and Paulista Geradora de Energia. Although SABESP has no majority interest in the capital stock of these companies, the shareholders’ agreements provide for the power of veto and casting vote in certain issues jointly with associates, indicating the shared control in the management of investees, except for Saneaqua Mairinque, which, as of August 2020, no longer has a shared control. Economic instability worsened by COVID-19 The global economic instability worsened in early 2020 with the outbreak of a new coronavirus, which was considered pandemic by the World Health Organization (WHO). Accordingly, SABESP has been taken several preventive measures to ensure the continuity and quality of the services provided to the population, which have become even more essential. It is worth noting that any interruption in water supply by a basic sanitation company may compromise compliance with WHO’s recommendations for everyone to keep good hygiene habits, such as washing hands correctly and more frequently. The Company implemented a number of preventive measures so that its employees are not exposed to situations of risks, such as: (i) employees from the administrative sectors (especially) and those with more than 60 years of age are working under a remote system; (ii) restriction of domestic and international trips; (iii) anticipation of the influenza and pneumonia vaccination campaign, (iv) closing of all branches that assist the public, concentrating services in the digital channels, to protect customers and employees; among others. Regarding the effects of Covid-19, we highlight the migration of billed volume from the public, commercial and industrial categories that have higher average tariffs to the residential category, which showed a slight recovery in 2021 when compared to 2020. Expenses with allowance for doubtful accounts still show a significant growth due to the increase in delinquency in the period. Management expects that with the gradual resumption of economic activities, improved water security, due to the works carried out, the generation of operating cash, added to the credit lines available for investments, the financial resources will be sufficient to honor its commitments and not jeopardize the necessary investments. New Legal Sanitation Framework On July 15, 2020, the Brazilian President sanctioned Federal Law 14,026/2020, known as the New Legal Framework for Basic Sanitation. The new law expands competition in the sector, by extinguishing program contract. Additionally, the New Legal Framework imposes performance goals to reach 99% of the population served with drinking water and 90% with sewage collection and treatment by December 31, 2033, encouraging operators to increase efficiency. It also granted the Water and Basic Sanitation National Agency (ANA) with authority to edit reference rules to regulate sanitation with a view to minimize regulatory uncertainties, thus creating a more stable and attractive environment for investments in the sector. On May 31, 2021, Federal Decree No. 10,710 was edited, which regulates Art. 10-B of Law No. 11,445/2007, establishing the methodology for proving the economic and financial capacity of providers of public services for the supply of drinking water and sanitary sewage, with a view to enabling the achievement of universalization goals by 2033. The aforementioned regulation imposes metrics for the economic-financial evaluation of service providers to prove their ability to make investments within the intended period, in addition to a series of conditions so that the contracts in force can be considered regular, whose eventual adaptations must occur until March 31, 2022, in line with the provisions of Art. 11-B, §1, of the new law. According to the aforementioned Decree, as of December 30, 2021, the Company presented a requirement to the São Paulo State Utility Services Regulatory Agency (ARSESP) containing documents that prove its capacity to maintain the provision of services in the operated area to meet the goals of universal water and sewage collection and treatment by 2033, defined by the New Legal Framework, attested by the independent auditor and certifying body and at an extraordinary meeting held on March 28, 2022, ARSESP unanimously resolved to recognize the proven economic and financial capacity of Sabesp, as described in note 34. In this new context, the Company understands it is important to highlight that i) it has contracts that already include goals that meet or even anticipate those defined by the New Legal Framework, which correspond to around 70% of revenue; ii) it has access to public capital and the private capital market due to its sound reputation, favoring the maintenance and/or expansion of its operating base and compliance with the universalization of services within the deadline established by the new law; iii) it has high governance level; and iv) it has current contracts with the granting authorities that ensure 95% of revenue. Approvals The financial statements were approved by Management on April 27, 2022.

Basis of preparation and presen

Basis of preparation and presentation of the financial statements	12 Months Ended
	Dec. 31, 2021
Basis of preparation and presentation of the financial statements	2 Basis of preparation and presentation of the financial statements The financial statements of the Company have been prepared in accordance with the International Financial Reporting Standards – IFRS as issued by the International Accounting Standards Board – IASB. All material information related to the financial statements, and this information alone, is being disclosed and corresponds to the information used by the Company’s Management in its administration. The financial statements have been prepared under the historical cost except for certain financial instruments measured at fair value when required by the standards. The preparation of financial statements in conformity with IFRS requires the use of certain critical accounting estimates. It also requires Management to exercise its judgment in the process of applying the Company's accounting policies. The areas involving a higher degree to judgment or complexity, or areas where assumptions and estimates are significant to the financial statements are described in Note 6.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Summary of Significant Accounting Policies	3 Summary of Significant Accounting Policies The main accounting policies applied in the preparation of these financial statements are defined below. These policies have been applied consistently in all years presented. 3.1 Cash and cash equivalents Cash and cash equivalents include cash in hand, bank deposits, overdraft accounts and other short-term highly liquid investments with maturities and intention of use by the Company’s Management in a period lower than three months. 3.2 Financial assets and liabilities Financial Asset - Classification The Company classified its financial assets according to the following categories: measured at amortized cost, measured at fair value through other comprehensive income and measured at fair value through profit or loss. The classification depends on the purpose for which the financial assets were acquired. Management determines the classification of the financial assets at inception. As of December 31, 2021 and 2020, the Company did not have financial assets classified as fair value through other comprehensive income and fair value through profit or loss. • Amortized cost This comprises financial assets that meet the following conditions: (i) it is held within the business model whose objective is to hold financial assets to collect contractual cash flows; and (ii) the contractual terms of the financial asset give rise, on specified dates, to cash flows that are solely payments of principal and interest on the principal amount outstanding. Presented as current assets, except for those with maturity of more than 12 months after the reporting date (these are classified as noncurrent assets). The Company's financial assets measured at amortized cost include cash and cash equivalents, financial investments, restricted cash, balances of trade receivables, accounts receivable from related parties, other receivables, receivables from the Water and Basic Sanitation National Agency – ANA. Financial assets measured at amortized cost are recorded at fair value and subsequently at amortized cost, under the effective interest rate method, except for trade receivables, which is initially measured at transaction price, as it contains no financing items, and is subsequently measured at amortized cost. Financial Liabilities - Classification The Company classifies its financial liabilities measured at amortized cost. Classification depends on the purpose to which the financial liabilities were assumed. This category comprises balances payable to contractors and suppliers, borrowings and financing, services payable, balances payable from public-private partnership (PPP), and program contract commitments. The effective interest rate method is adopted to calculate the amortized cost of a financial liability and allocate its interest expense under the respective period. The effective interest rate exactly deducts the estimated future cash flows (including fees, transaction costs and other issue costs) throughout the financial liability’s estimated life or, when appropriate, during a shorter period, for initial recognition of the net carrying amount. Impairment of financial assets Trade receivables Due to the charactheristics of the Company’s accounts receivable such as (i) insignificant financial component, (ii) non-complex receivables portfolio, and (iii) low credit risk, the Company adopted the simplified approach of expected credit loss, which consists in recognizing the expected credit loss based on the total asset’s useful life. The methodology to calculate allowance for doubtful accounts consisted of using an estimate calculated based on the average default observed in the last 36 months, per maturity range, in addition to estimating the recovery of credits overdue for more than 360 days, based on the track record of the last three years. For estimate purposes, it also considered the category of private and public customers, and segregated accounts receivable among the regular consumption accounts and agreements. The Company also concluded that the estimates of the macroeconomic indicators Gross Domestic Product (GDP), Unemployment Rate and the Extended Consumer Price Index (IPCA) were not impacted, given that it carried out correlation analyses of these indicators and its default history, which did not result in significant correlation between them. Deposit transactions and financial investments measured at amortized cost The Company analyzes changes in the rates of investments in bank deposits certificates and information obtained from regulatory agencies about the financial institutions. The likelihood of delinquency over 12 months and during the terms of these investments was based on historical data provided by credit rating agencies for each credit level and analyzed in terms of sensitivity based on current returns. These deposits and financial investments are subject to an insignificant risk of change in value. 3.3 Operating income (a) Revenue from sanitation services Revenue from water supply and sanitation services are recognized as the water is consumed and services are provided. Revenues, including unbilled revenues, are recognized at the fair value of the consideration received or receivable for the rendering of those services. Revenue is shown net of value-added tax, rebates and discounts. Unbilled revenues represent incurred revenues in which the services were provided, but not yet billed until the end of the each period and are recorded as trade receivables based on monthly estimates of the completed services. Revenues are recognized based on IFRS 15 (Revenue from Contracts with Customers), which establishes a five-step model applicable over revenue from a contract with a customer. Revenues are recognized when the Company: i) it identifies the contracts with customers; ii) it identifies the different obligations in the contract; iii) it determines the transaction price; iv) it allocates the transaction price to the performance obligations in the contracts; and (v) it satisfies all performance obligations. Disputed amounts are recognized as revenue when collected. (b) Construction revenue Revenue from concession construction contracts is recognized in accordance with IFRS 15 (Revenue from Contracts with Customers) and IFRIC 12 (Service Concession Arrengements), as all performance obligations are satisfied over time. During the construction phase of the contract, an asset is classified as contract assets, as the Company estimates that the fair value of its consideration is equivalent to expected construction costs plus margin. The fee represents the additional margin related to the work performed by the Company in relation to such construction contracts and it is added to construction costs, resulting in the construction revenue. 3.4 Trade receivables and allowance for doubtful accounts Trade receivables are amounts due from customers for services performed in the ordinary course of business. These are classified as current assets, except when maturity exceeds 12 months after the end of the reporting period. In these cases, they are presented as noncurrent assets. The Company establishes an allowance for doubtful accounts for receivable balances at an amount that Management considers to be sufficient to cover eventual losses, as described in note 3.2. 3.5 Inventories Inventories comprise supplies for consumption and maintenance of the water and sewage systems are stated at the lower of average cost of acquisition or net realizable value, and are classified in current assets. 3.6 Investment properties Investment properties are recorded at the acquisition or construction cost, less accumulated depreciation, except for the land group, calculated by the straight-line method at rates that consider the estimated useful life of the assets. Expenditures related to repairs and maintenance are recorded in the income statement when incurred. The Company also maintains some assets for undetermined use in the future, i.e. it is not defined if the Company will use these assets in the operation or sell them in the short term during the ordinary course of business. 3.7 Contract asset The Contract Asset (works in progress) is the right to consideration in exchange for goods or services transferred to the customers. As determined by IFRS 15 - Revenue from contract with customer, assets related to the concession under construction, recorded under the scope of IFRIC 12 – Service Concession Arrengements, should be classified as contract asset during the construction period and transferred to the intangible assets only after the completion of the works. A contract asset is initially recognized at fair value and includes construction margin and borrowing costs capitalized in qualifying assets, when applicable, during the period in which the asset is in the construction phase, based on the weighted average rate of borrowings in effect on the capitalization date. A qualifying asset is an asset that necessarily requires a substantial period of time to be ready for its intended use or sale. 3.8 Property, plant and equipment Property, plant and equipment comprise mainly administrative facilities not composing the assets, subject-matter of the concession agreements. Those assets are stated at historical acquisition or construction cost less depreciation, net of impairment losses, when necessary. Interest, other finance charges and inflationary effects resulting from financing effectively applied to construction in progress are recorded as cost of respective property, plant and equipment, in this case, for the qualifying assets, as applicable. Qualifying assets are assets that, necessarily, required a substantial period to get ready for its intended use or sale. The Company defined that this period is higher than 12 months. Subsequent costs included in the existing asset's carrying amount or recognized as a separate asset, as appropriate, only when it is probable that the future economic benefit associated with the item will flow to the Company and the cost of the item can be reliably measured. Repairs and maintenance are charged to the income statement of the year, as incurred. Depreciation is calculated using the straight-line method to allocate their cost and the average rates are presented in Note 16 (a). Land is not depreciated. Residual values and the useful life of assets are revised and adjusted, where applicable, at the end of each year. Gain and losses on disposals are determined by the difference between the proceeds with the carrying amount and are recognized in other operating income (expenses) in the income statement. 3.9 Intangible assets Intangibles are stated at acquisition cost and/or construction of the underlying assets, including construction margin, interest and other finance charges capitalized during the construction period, in this case, for the qualifying assets. Qualifying assets are assets that, necessarily, take a substantial period to get ready for its intended use or sale. The Company considers that substantial period means a period greater than 12 months. This period was established by considering the completion period of the majority of its constructions, which is greater than 12 months, which corresponds to one fiscal year of the Company. The intangible has its amortization initiated when the intangible assets are available for use in location and the necessary condition when this asset becomes operational. The amortization of the intangible assets is discontinued when the asset is totally consumed or it is disposed of, whatever occurs first. Donations in assets, received from third parties and governmental entities, to allow the Company to render water and sewage services are recorded in the Company’s financial statements at zero cost, since these assets are controlled by the concession grantor. Financial resources received as donations for the construction of infrastructure are recorded under “Other operating income”. (a) Concession agreements/program contracts/service contracts The Company operates concession agreements including the rendering of basic sanitation, environmental, water supply and sewage services signed with the concession grantor. The infrastructure used by SABESP subject to service concession arrangements is considered to be controlled by the concession grantor when: (i) The grantor controls or regulates what services the operator must provide with the infrastructure, to whom it must provide them, and at what price; and (ii) The grantor controls the infrastructure, i.e., retains the right to take back the infrastructure at the end of the concession. The rights over the infrastructure operated under the concession agreements are accounted for as an intangible asset as the Company has the right to charge for the use of the infrastructure assets, and the users (consumers) have the primary responsibility to pay SABESP for the services. The fair value of construction and other works on the infrastructure is recognized as revenue, as its fair value, when the infrastructure is built, provided that this work is expected to generate future economic benefits. The accounting policy to recognize construction revenue is described in Note 3.3 (b). The details referring to amortization of intangible assets are described in Note 15 (c). (b) Software license of use Software licensing is capitalized based on the acquisition costs and other implementation costs. Amortizations are recorded according to the useful life and the expenses associated with maintaining them are recognized as expenses when incurred. 3.10 Impairment of non-financial assets Property, plant and equipment, intangible assets and other noncurrent assets with defined useful lives, are yearly reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The Company does not have assets with indefinite useful life and assessed that there are no indications of impairment losses, mainly supported by Law 14,026/2020, which ensures that basic sanitation public utilities will have assured its economic and financial sustainability to public sanitation services through tariffs or indemnity. 3.11 Trade payables and contractors Trade payables and contractors are obligations to pay for goods or services acquired from suppliers in the ordinary course of business and are initially measured at fair value, which generally correspond to the bill and subsequently at amortized cost, being classified as current liabilities, except when the maturity exceeds 12 months after the reporting date and are, otherwise, being presented as noncurrent liabilities. 3.12 Borrowings and financing Borrowings and financing are initially recognized at fair value, upon receipt of funds, net of transaction costs. Subsequently, borrowings and financing are stated at amortized cost, as presented in Note 17. Borrowings and financing are classified as current liabilities unless the Company has an unconditional right to defer the settlement of the liability for at least 12 months after the end of the reporting date. Nonconvertible bonds issued by the Company are recognized in a similar manner to borrowings. 3.13 Borrowing costs Borrowing costs attributable to acquisition, construction or production of an asset, which, necessarily, requires a substantial time period to be ready for use or sale are capitalized as part of the cost of these assets. Other borrowing costs are recognized as expenses in the period they are incurred. Borrowing costs are interest rates and other charges incurred by the Company related to borrowings, including exchange variation, as described below. The capitalization occurs during the period in which the asset has been built, considering the weighted average rate of borrowings effective on the capitalization date. For foreign currency-denominated borrowings or financing, the Company analyzes them as if they were contracted in local currency, restricting the capitalization of interest and/or exchange variation by the amount that would be capitalized if these were contracted in the domestic market in similar lines of credit and loans. 3.14 Salaries, payroll charges and contributions Salaries, vacations, Christmas bonus, profit sharing and additional payments negotiated in collective labor agreements plus related charges and contributions are recorded on the accrual basis. The profit sharing plan for its employees is based on operational and financial targets, and a provision is created when it is contractually required or when there is a past practice that created a constructive obligation, and is recorded on the accrual basis period as operating cost, selling and administrative expenses or capitalized in assets. 3.15 Provisions, legal obligations, escrow deposits and contingent assets Provisions related to claims are recognized when: i) the Company has a present (legal or constructive) obligation resulting from a past event; ii) it is probable that an outflow of resources that comprise economic benefits will be required to settle the obligation; and iii) the amount can be reliably estimated. Where there are a number of similar obligations, the likelihood that an outflow of resources will be required to settle an obligation is determined by considering the nature of the obligations as a whole. Provisions are measured at the present value of the disbursements expected to be required to settle the obligation using a pre-tax rate that reflects current market assessments of the time value of money and the risks specific to the obligation. The increase in the provision due to the passage of time is recognized as financial expense. For financial statement presentation purposes, the provision is stated net of escrow deposits, based on the legal offset right. Escrow deposits not linked to the related obligations are recorded in noncurrent assets. Escrow deposits not linked to the related obligations are recorded in noncurrent assets and adjusted by the indexes defined by the competent authorities. The Company does not recognize contingent liabilities in the financial statements since it either does not expect outflows to be required or the amount of the obligation cannot be reliably measured. Contingent assets are not recognized in the statements of financial position. 3.16 Environmental costs Costs related to ongoing environmental programs are expensed in the income statement, when there is any indication of an event. Ongoing programs are designed to minimize the environmental impact of the operations and to manage the environmental risks inherent to the Company's activities. 3.17 Income taxes – current and deferred Income taxes expenses comprise current and deferred income tax and social contributions. Current taxes The provision for income tax and social contribution is calculated based on the taxable income for the year and the rates effective at the end of the year. The income tax was accrued at rate of 15%, plus 10% surtax on taxable income exceeding R$ 240 9 Deferred taxes Deferred income tax is recognized, using the liability method, on temporary differences arising between the tax basis of assets and liabilities and their carrying amounts in the financial statements. However, the deferred income tax is not accounted for if it arises from initial recognition of an asset or liability in a transaction that at the time of the transaction affects neither accounting nor taxable profit nor loss, except for business combinations. Deferred income tax is determined using tax rates (and laws) effective at the end of the reporting period and expected to apply when the related deferred income tax asset is realized or the deferred income tax liability is settled. Deferred income tax and social contribution assets are recognized only to the extent that it is probable that future taxable profit will be available for which temporary differences can be utilized and tax losses can be carryforward. Deferred taxes assets and liabilities are offset when there is a legally enforceable right of offsetting current tax assets against current tax liabilities and when deferred income tax assets and liabilities are related to income taxes levied by same tax authority over the tax entity. 3.18 Taxes on revenues Revenues from sanitation services are recognized on accrual basis for PASEP (Programa de Formação do Patrimônio do Servidor Público) and Cofins (Contribuição para o Financiamento da Seguridade Social), calculated at the rates of 1.65 7.60 The taxes related to PASEP and Cofins incident on amounts invoiced to public entities are due when invoices are received. These taxes are calculated by the non-cumulativeness regime and presented net, as deductions from gross revenues. Tax debts calculated over “other operating income” are presented as deductions from the respective operating income. In addition, revenues from sanitation services are also subject to the Regulatory, Control and Oversight Fee (TRCF - Taxa de Regulação, Controle e Fiscalização), whose taxable event is the performance of regulatory, control and monitoring activities by ARSESP, calculated at 0.50 3.19 Pension plan obligations (a) Defined benefit The Company makes contributions to defined benefit plans on a contractual basis and sponsored thereby. The regular contributions comprise the net administrative expenses and are recognized in the income statement for the period. Liabilities from defined benefit pension plan obligations correspond to the present value of the defined benefit obligation at the end of the reporting period, less the fair value of the plan’s assets. The defined benefit obligation (G1) and (G0) are calculated on an annual basis by independent actuaries, using the projected unit credit method. The estimated future cash outflow is discounted to its present value, using the interest rates of Government bonds with maturities that approximate the maturity of the related liability. Referring to actuarial gains and losses deriving from adjustments based on the experience and changes in actuarial assumptions are directly recorded under equity, as other comprehensive income (OCI), so that the plan's net assets or liabilities are recognized in the statement of financial position in order to reflect the full amount of plan’s deficit or surplus. In an event where a curtailment relates to only some of the employees covered by a plan, or where only part of an obligation is settled, the gain or loss includes a proportionate share of the past service cost and actuarial gains and losses. The proportionate share is determined on the basis of the present value of the obligations before and after the curtailment or settlement. (b) Defined contribution The Company makes contributions to defined contribution plans on a contractual basis and sponsored thereby, a supplementary private pension entity that provides post-employment benefits to its employees, in which the Company makes fixed and equal contributions to employees, within the limits set by regulation. In this model, the benefits paid are directly related to the amount contributed, with no deficits to be covered by the Company. 3.20 Financial revenues and expenses Financial revenue is primarily comprised of interest and inflation adjustments resulting from financial investments, escrow deposits and negotiations with customer to pay by installments, calculated using the effective interest rate method. Financial expenses are primarily comprised of interest, inflation adjustments and exchange rate changes on borrowings and financing, provisions, public-private partnership and program contract commitments. These financial income and expenses are calculated using the effective interest rate method. Inflation adjustments and exchange gains and losses derive from the collection or payment to third parties, as contractually required by law or court decision, and recognized on an accrual basis pro rata temporis. Inflation adjustments included in the agreements are not considered embedded derivatives, since they are deemed as inflation adjustment rates for the Company’s economic scenario. 3.21 Leases Leases are recognized at the present value of the contractual obligations, presented in assets as Right of Use (Note 15 (j)) and in liabilities as Leases (Note 17 (b)), except for short-term contracts (12 months or less) and/or low value (below US$ 5 thousand), which are recorded in the income statement recognized as an expense when incurred. 3.22 Other current and noncurrent assets and liabilities Other assets are stated at acquisition cost, net of any impairment loss, where applicable. The amounts recognized as other liabilities are stated at known or estimated amounts, including, where applicable, related charges and inflation adjustments. 3.23 Dividends and interest on capital The Company uses the tax benefits of distributing dividends as interest on capital, as permitted by Brazilian Law and based on the Bylaws. This distribution of dividend is accounted for in accordance with Brazilian Law 9,249/95 for tax deductibility purposes, limited to the daily pro rata fluctuation of the Long-term Interest Rate (TJLP). The benefit attributed to the shareholders is recognized in the current liability against Equity, based on its by-laws. Dividends and interest on capital over the minimum established in the by-laws are recognized when approved by the shareholders in the shareholders’ meeting, except for taxes incurring in the distribution of interest on capital. The tax benefit of the interest on capital is accrued in the income statement of the year, under the same recognition basis of expenses with interest on capital. 3.24 Present value adjustment Current and noncurrent financial assets and liabilities arising from long- or short-term transactions are adjusted to present value based on market discount rates as of the transaction date, when the effects are significant. 3.25 Segment information Operating segments are determined in a manner consistent with the internal reporting to the Company’s chief operating decision maker (“CODM”), which, in the case of SABESP, is comprised of the Board of Directors and Board of Executive Officers, to make strategic decisions, allocate resources and evaluate performance. Consequently, the Company determined that it has one operating segment which is sanitation services. The accounting policies used to determine segment information are the same as those used to prepare the Company’s financial statements. The measure of the segment’s profit or loss is operating income before other operating expenses, net and equity accounting, which excludes construction revenue and related costs. The CODM analyzes asset and liabilitity information on a consolidated basis. Consequently, the Company does not disclose segment information on assets and liabilities. Substantially all of the Company’s noncurrent assets and revenue generated from customers are located in São Paulo State. Consequently, financial information is not disclosed by geographic area. 3.26 Translation into foreign currency (a) Functional and reporting currency Items included in the financial statements are measured using the currency of the primary economic environment in which the company operates ("the functional currency"). The financial statements are presented in Brazilian reais (R$), which is also the Company's functional currency. All financial information has been stated in reais and rounded to the next thousand, except where otherwise indicated. (b) Foreign currency translation Foreign currency-denominated transactions are translated into Brazilian reais using the exchange rates prevailing at the transaction dates. Statement of financial position accounts are translated by the exchange rate prevailing at reporting date. Exchange gains and losses resulting from the settlement of these transactions and the translation of foreign currency-denominated cash assets and liabilities are recognized in the income statement, except for borrowings and financing referring to property, plant and equipment or intangible assets in progress, where exchange losses are recognized as corresponding entry to the asset while construction is in progress, as described in Note 3.12.

Changes in accounting practices

Changes in accounting practices and disclosures	12 Months Ended
	Dec. 31, 2021
Changes in accounting practices and disclosures	4 Changes in accounting practices and disclosures 4.1 New standards, amendments and interpretations effective for periods beginning on or after January 1, 2021 New standards and revisions Standard Description Impact Amendments to IFRS 4 – Insurance Contracts, IFRS 7 – Financial Instruments: Disclosures, IFRS 9 – Financial Instruments, IFRS 16 – Leases Describes the amendments to the Reference Interest Rate Reform – Phase 2. The adoption of these amendments reflects the effects of the transition from interbank offered rates (“IBOR”) to alternative reference interest rates (also called interest-free rates risk or “risk free rates – RFRs”). The application of these amendments did not impact the disclosures or amounts recognized in the annual financial statements. Amendment to IFRS 16 – COVID-19 - Related Rent Concessions Establishes practical measures for lessees in the accounting for lease concessions that occurred as a direct result of COVID-19. Under the practical expedient, a lessee is not required to assess whether a COVID-19-related lease concession is a lease modification. The application of this amendment did not impact the disclosures or amounts recognized in the annual financial statements. 4.2 New standards, amendments and interpretations to existing standards that are not yet effective The Company did not early adopt these standards and is assessing the impacts of the new and revised IFRS below on the disclosures or amounts recognized in the financial statements: Standard Description Impact IFRS 17 – Insurance Contracts 2 Establishes the principles for the recognition, measurement, presentation and disclosure of insurance contracts. IFRS 17 will supersede IFRS 4 Insurance Contracts. The Company does not expect effects from adopting this standard. Amendments to IFRS 10 - Consolidated Statements and IAS 28 – Sale or Contribution of Assets between an Investor and its Associate or Joint Venture 3 Clarify situations that involve the sale or contribution of assets between an investor and its associates or joint venture. The Company is assessing the impacts and effects of the amendments; however, it does not expect any effects from the amendments. Amendments to IAS 1 – Classification of Liabilities as Current or Non-Current 2 These amendments to IAS 1 only affect the presentation of liabilities as current or non-current in the statement of financial position and not the amount or the time of recognition of any asset, liability, income or expense, or the information disclosed on such items. In addition, clarify that the classification of liabilities as current or non-current is based on the rights existing at the balance sheet date, specify that the classification is not affected by the expectations on whether an entity will exercise its right to postpone the settlement of the liability and introduce the definition of 'settlement' to clarify that settlement refers to the transfer to a counterparty, of cash, equity instruments, other assets or services. The Company does not expect any impacts from this standard. Amendments to IFRS 3 – Reference to the Conceptual Framework 1 The amendments update IFRS 3 so that it refers to the 2018 Conceptual Framework, not to the 1989 Framework. The amendments also include in IFRS 3 the requirement that, for obligations within the scope of IAS 37, the acquirer applies this standard to identify whether there is an obligation at the acquisition date arising from past events. For a tax within the scope of IFRIC 21 - Taxes, the acquirer applies IFRIC 21 to determine whether the event that resulted in the obligation to pay the tax occurred up to the date of acquisition date. Finally, the amendments add an explicit statement that the acquirer does not recognize contingent assets acquired in a business combination. The Company does not expect effects from this standard. Standard Description Impact Amendments to IAS 16 – Proceeds Before Intended Use 1 The amendments prohibit deducting from the cost of an item of property, plant and equipment any proceeds from the sale of items produced before the asset is available for use, i.e. proceeds to bring the asset to the location and in the condition necessary for it to be able to operate as intended by the Company. Consequently, the entity recognizes these proceeds from the sale and corresponding costs in the result and measures the costs of these items in accordance with IAS 2 - Inventories. The Company does not expect effects from this standard. Standard Description Impact Amendments to IAS 37 – Onerous Contracts – Cost of Compliance with the Contract 1 The amendments specify that the contract's "compliance cost" comprises costs directly related to the contract, which are the incremental costs of compliance with that contract (such as employees or materials) and the allocation of other costs directly related to contract compliance (such as allocation of depreciation expenses for an item of property, plant and equipment used in fulfilling the contract). The Company does not expect effects from this standard. Amendments to IAS 1 – Presentation of Financial Statements and IFRS Practice Statement 2 – “Making Materiality Judgments” – Disclosure of Accounting Policies 4 The amendments modify the requirements contained in IAS 1 regarding the disclosure of accounting policies. The amendments replace all the examples of the term “significant accounting policies” with “relevant accounting policy information”. Accounting policy information is material if, when considered together with other information included in an entity's financial statements, it could reasonably influence the decisions of key users of general purpose financial statements made on the basis of those financial statements. The supporting paragraphs have also been amended to clarify that accounting policy information relating to non-important transactions, other events or conditions is immaterial and need not be disclosed. The Company does not expect effects from these amendments. Standard Description Impact Amendments to IAS 8 - Accounting Policies, Changes in Accounting Estimates and Errors—Definition of Accounting Estimates 2 The amendment supersede the definition of change in accounting estimates with the definition of accounting estimates. According to the new definition, accounting estimates are “monetary amounts in the financial statements subject to measurement uncertainty”. The Company does not expect effects from these amendments. Amendments to IAS 12 – Income Taxes – Deferred Tax Related to Assets and Liabilities Resulting from a Single Transaction (“single transaction”) 2 The amendments introduce an additional exception to the exemption of first-time recognition. According to the amendments, an entity does not apply the exemption of first-time recognition for transactions resulting in equal taxable and deductible temporary differences. The Company does not expect effects from these amendments. Standard Description Impact Annual improvements to IFRSs: 2018-2020 Cycle Amendments to IFRS 1 – First-time Adoption of International Financial Reporting Standards 1 1 1 IFRS 1 – First-Time Adoption of International Accounting Standards - provides for an additional measure for a subsidiary that becomes an initial adopter after its parent company with respect to accounting for accumulated translation differences. The Company does not expect effects from these amendments. 1 Effective for annual periods beginning on or after January 1, 2022. 2 Effective for annual periods beginning on or after January 1, 2023. 3 The effective date of the amendments has not yet been defined by IASB. 4 The amendments to IFRS Practice Statement 2 do not have an effective date or transition requirements. There are no other standards and interpretations not yet adopted that may, in the opinion of Management, have a significant impact on the result for the year of equity disclosed by the Company in its financial statements.

Risk Management

Risk Management	12 Months Ended
	Dec. 31, 2021
Risk Management	5 Risk Management 5.1 Financial Risk Management Financial risk factors The Company's activities are affected by Brazilian economic scenario, making it exposed to market risk (exchange rate and interest rate), credit risk and liquidity risk. Financial risk management is focused on the unpredictability of financial markets and seeks to minimize potential adverse effects on the Company’s financial performance. The Company has not utilized derivative instruments in any of the reported periods. (a) Market risk Foreign currency risk Foreign exchange exposure implies market risks associated with currency fluctuations, since the Company has foreign currency-denominated liabilities, arising from long-term funding, in development institutions, at more attractive interest rates, in U.S. dollars and Yen The management of currency exposure considers several current and projected economic factors, besides market conditions. This risk arises from the possibility that the Company may incur in losses due to exchange rate fluctuations that would impact liability balances of foreign currency-denominated borrowings and financing raised in the market and related financial expenses. The Company does not maintain hedge or swap contracts or any derivative financial instrument to hedge against this risk. Part of the financial debt, totaling R$ 3.321.489 3,563,170 The exposure to exchange risk is as follows: Schedule of exposure to exchange risk December 31, 2021 December 31, 2020 Foreign currency (in thousands) R$ Foreign currency (in thousands) R$ Borrowings and financing – US$ 163,538 912,624 167,479 870,338 Borrowings and financing – Yen 49,324,813 2,390,774 52,969,560 2,671,255 Interest and charges from borrowings and financing – US$ 4,121 5,540 Interest and charges from borrowings and financing – Yen 13,970 16,037 Total exposure 3,321,489 3,563,170 Borrowing cost – US$ (22,486) (12,342) Borrowing cost – Yen (2,850) (2,966) Total foreign-currency denominated borrowings (Note 17) 3,296,153 3,547,862 The 7.1 The table below shows the exchange rate variation for the period: December 31, 2021 December 31, 2020 Variation US$ R$ 5.5805 R$ 5.1967 7.4 Iene R$ 0.04847 R$ 0.05043 -3.9 In 2021, there was a decrease in the liabilities of borrowings and financing contracts, in the amount of R$ 251,709 2,811 332,149 356,317 The probable scenario below presents the effect in the income statements for the next 12 months considering the projection of the U.S. dollar and the yen. The Company understands that the scenario presented is reasonable, given the instability of the Brazilian real against the U.S. dollar and the Yen. Scenario I (Probable) (*) Net currency exposure as of December 31, 2021 in US$ - Liabilities 163,538 US$ rate as of December 31, 2021 5.5805 Exchange rate estimated according to the scenario 5.6000 Difference between the rates ( 0.0195 Effect on the net financial result R$ - gain/(loss) (3,189) Net currency exposure as of December 31, 2021 in Yen - Liabilities 49,324,813 Yen rate as of December 31, 2021 0.04847 Exchange rate estimated according to the scenario 0.05093 Difference between the rates (0.00246) Effect on the net financial result R$ - gain/(loss) (121,339) Total effect on the net financial result in R$ - gain/(loss) (124,528) (*) For the probable scenario in U.S. dollar, the exchange rate estimated for December 31, 2022 was used, according to the BACEN Focus Report of December 31, 2021. For the Yen, the exchange rate estimated for December 31, 2022 was used, according to B3’s Reference Rates report of December 31, 2021. Interest rate risk This risk arises from the possibility that the Company could incur losses due to fluctuations in interest rates, increasing the financial expenses related to borrowings and financing. The Company has not entered into any derivative contract to hedge against this risk; however continually monitors market interest rates, in order to evaluate the possible need to replace its debt. The table below provides the Company's borrowings and financing subject to variable interest rates: December 31, 2021 December 31, 2020 CDI (i) 7,612,299 7,836,988 TR (ii) 1,638,079 1,619,416 IPCA (iii) 3,019,459 2,176,547 TJLP (iv) 1,478,740 1,517,657 LIBOR (v) 912,626 870,337 Interest and charges 243,696 164,439 Total 14,904,899 14,185,384 (i) CDI – (Certificado de Depósito Interbancário), an interbank deposit certificate (ii) TR – Interest Benchmark Rate (iii) IPCA – (Índice Nacional de Preços ao Consumidor Amplo), a consumer price index (iv) TJLP – (Taxa de Juros a Longo Prazo), a long-term interest rate index (v) LIBOR – London Interbank Offered Rate Another risk to which the Company is exposed, is the mismatch of monetary restatement indices of its debts with those of its service revenues. Tariff adjustments of services provided by the Company do not necessarily follow the increases in the inflation indexes to adjust borrowings, financing and interest rates affecting indebtedness As of December 31, 2021, if interest rates on borrowings and financing had been 1 percentage point higher or lower with all other variables held constant, the effects on profit before taxes would have been R$ 149,049 141,854 (b) Credit risk Credit risk arises from cash and cash equivalents, financial investments, as well as credit exposures to wholesale basis and retail customers, including outstanding accounts receivable, restricted cash and accounts receivable from related parties. Credit risk exposure to customers is mitigated by sales to a dispersed base. The maximum exposures to credit risk as of December 31, 2021 is the carrying amount of instruments classified as cash and cash equivalents, financial investments, restricted cash, trade receivables and accounts receivable from related parties in the balance sheet date. See additional information in Notes 7, 8, 9, 10 and 11. Regarding the financial assets held with financial institutions, the credit quality was assessed by reference to external credit ratings (if available) or to historical information about the bank’s default rates. For the credit quality of the banks, such as deposits and financial investments, the Company considers the lower rating published by three main international rating agencies (Fitch, Moody's and S&P), according to internal policy of market risk management: Banks Fitch Moody's Standard Poor's Banco do Brasil S/A AA(bra) AAA.br - Banco Santander Brasil S/A - AAA.br brAAA Brazilian Federal Savings Bank AA(bra) AAA.br brAAA Banco Bradesco S/A AAA(bra) AAA.br brAAA Itaú Unibanco Holding S/A AAA(bra) AAA.br brAAA Banco BV - AA.br brAAA Banco BTG Pactual S/A AA(bra) AAA.br brAA+ The table below shows the rating assessment released by the Fitch agency, for deposit transactions and financial investments in local currency (R$ - domestic rating): December 31, 2021 December 31, 2020 Cash and cash equivalents and financial investments AA(bra) 1,905,810 2,662,685 AAA(bra) 970,474 891,243 Other (*) 275,030 253,619 3,151,314 3,807,547 (*) This category includes current accounts and financial investmets in banks referring to Banco BV in the amount of R$ 262,465 253,066 (c) Liquidity risk Liquidity is primarily reliant upon cash provided by operating activities and borrowings and financing obtained in the local and international capital markets, as well as the payment of debts. The liquidity risk management considers the assessment of its liquidity requirements to ensure it has sufficient cash to meet its operating and capital expenditures needs, as well as the payment of debts. The funds held by the Company are invested in interest-bearing current accounts, time deposits and securities, selecting instruments with appropriate maturity or liquidity sufficient to provide margin as determined by projections mentioned above. The table below shows the financial liabilities of the Company, by relevant maturities, including the installments of principal and future interest to be paid according to the agreement. Future interest was calculated based on the contractual clauses for all agreements. For agreements with floating interest rate, the interest rates used correspond to the base dates above. 2022 2023 2024 2025 2026 2027 onwards Total As of December 31, 2021 Liabilities Borrowings and financing 2,767,867 2,749,335 2,939,155 2,976,535 2,721,792 12,484,891 26,639,575 Trade payables and contractors 236,763 — — — — — 236,763 Services payable 469,027 — — — — — 469,027 Public-Private Partnership – PPP 429,942 430,440 379,684 351,586 351,586 4,068,466 6,011,704 Program Contract Commitments 77,465 36,442 1,126 1,126 1,126 12,983 130,268 Cross default The Company has borrowings and financing agreements including cross default clauses, e.g., the early maturity of any debt, may imply the early maturity of these agreements. The indicators are continuously monitored in order to avoid the execution of these clauses and the more restrictive are showed in Note 17 (c). (d) Sensitivity analysis on interest rate risk The table below shows the sensitivity analysis of the financial instruments, prepared in accordance with IFRS 7, in order to evidence the balances of main financial assets and liabilities, calculated at a rate projected for the twelve-month period after December 31, 2021, or until the final settlement of each contract, whichever is shorter, considering a likely scenario. The purpose of the sensitivity analysis is to measure the impact of changes in the market over the financial instruments, considering constant all other variables. In the time of settlement the amounts can be different from those presented, due to the estimates used in the measurement. December 31, 2021 Indicators Exposure Scenario I (Probable) Assets CDI 1,533,614 11.79 (**) Financial income 180,813 Liabilities CDI (7,612,299) 11.79 (**) Interest to be incurred (897,490) CDI net exposure (6,078,685) (716,677) Liabilities TR (1,638,079) 0.0276 (**) Expenses to be incurred (452) IPCA (3,019,459) 5.0302 (*) Expenses to be incurred (151,885) TJLP (1,478,740) 6.4400 (***) Interest to be incurred (95,231) LIBOR (912,626) 0.536 (**) Interest to be incurred (4,892) Total expenses to be incurred, net (969,137) (*) Source: Focus-BACEN Report of December 31, 2021 (**) Source: B3 of December 31, 2021 (***) Source: LCA Consultores of December 31, 2021 5.2 Capital management The Company’s objectives when managing capital are ensure its ability to continue as a going concern in order to provide returns for shareholders and benefits for other stakeholders, and to maintain an optimal capital structure to reduce the cost of capital. Capital is monitored based on the leverage ratio, which corresponds to net debt divided by total capital (shareholders and providers of capital). Net debt corresponds to total borrowings and financing less cash and cash equivalents and financial investments. Total capital is calculated as total equity as shown in the statement of the financial position plus net debt. December 31, 2021 December 31, 2020 Total borrowings and financing (Note 17) 17,723,836 17,258,624 (-) Cash and cash equivalents (Note 7) (717,929) (396,401) (-) Financial investments (Note 8) (2,433,385) (3,411,146) Net debt 14,572,522 13,451,077 Total equity 24,931,859 22,793,704 Total capital (shareholders + providers of capital) 39,504,381 36,244,781 Leverage ratio 37 37 As of December 31, 2021, the leverage ratio remained at 37 5.3 Fair value estimates The Company considers that balances from trade receivables (current) and trade payables and contractors by carrying amount, less impairment approximate their fair values, considering the short maturity. Long-term trade receivables also approximate their fair values, as they will be adjusted by inflation and/or will bear contractual interest rates over time. 5.4 Financial instruments The Company did not have financial assets classified as fair value through other comprehensive income and fair value through profit or loss. The Company’s financial instruments included in the amortized cost category comprise cash and cash equivalents, restricted cash, trade receivables, balances with related parties, other receivables, and balances receivable from the Water and Basic Sanitation National Agency – ANA, trade payables and contractors, borrowings and financing, services payable, balances payable deriving from the Public Private Partnership-PPP and program contract commitments, which are non-derivative financial assets and liabilities with fixed or determinable payments, not quoted in an active market, except for cash equivalents and financial investments. The estimated fair values of the financial instruments are as follows: Financial assets December 31, 2021 December 31, 2020 Carrying amount Fair value Carrying amount Fair value Cash and cash equivalents 717,929 717,929 396,401 396,401 Financial investments 2,433,385 2,433,385 3,411,146 3,411,146 Restricted cash 28,467 28,467 35,742 35,742 Trade receivables 2,918,311 2,918,311 2,450,986 2,450,986 Water and Basic Sanitation National Agency – ANA 20,666 20,666 26,463 26,463 Other assets 226,242 226,242 246,110 246,110 Additionally, SABESP has financial instrument assets receivables from related parties, in the amount of R$ 818,552 806,645 741,910 732,391 Financial liabilities December 31, 2021 December 31, 2020 Carrying amount Fair value Carrying amount Fair value Borrowings and financing 17,723,836 17,947,954 17,258,624 17,702,649 Trade payables and contractors 236,763 236,763 263,741 263,741 Services payable 469,027 469,027 453,750 453,750 Program contract commitments 122,647 122,647 231,480 231,480 Public-Private Partnership - PPP 3,060,185 3,060,185 3,175,273 3,175,273 To obtain fair value of borrowings and financing, the following criteria have been adopted: (i) Agreements with CEF (Brazilian Federal Savings Bank) were projected until their final maturities, at the average interest rate plus TR x DI and the average contractual term, were adjusted to present value by a funding rate specific for the Company in similar contracts, plus TR x DI, on the end of the reporting period. TR x DI rates were obtained with B3. (ii) The debentures were projected up to the final maturity date according to contractual rates (IPCA, DI, TJLP or TR), and adjusted to present value considering the future interest rate published by ANBIMA in the secondary market, or by equivalent market rates, or the Company’s shares traded in the Brazilian market. (iii) Financing – BNDES corresponds to instruments valued at their carrying amount restated until the maturity date, and are indexed by the long-term interest rate (TJLP) . These financings have specific characteristics and conditions defined in the financing agreements with BNDES, between independent parties, and reflect the conditions for these types of financing. Brazil does not have a consolidated market of long-term debts with the same characteristics of BNDES financing; thus, the offering of credit to the entities in general, with such long-term characteristics, is usually restricted to BNDES. (iv) Other financings in local currency are considered by carrying the amount restated until the maturity date, adjusted to present value at future market interest rates. The future rates used were obtained on the website of B3. (v) Agreements with IDB and IBRD were projected until final maturity in origin currency, using the contracted interest rates + Libor’s future rate, adjusted to present value using the exchange coupon curve obtained with B3, plus future LFT, disclosed by ANBIMA in the secondary market. All the amounts obtained were translated into Brazilian reais at the exchange rate of December 31, 2021. (vi) Agreements with JICA were projected until final maturity in origin currency, using the contracted interest rates, translated to the U.S. dollar and adjusted to present value using the exchange coupon curve obtained with B3, plus future LFT, disclosed by ANBIMA in the secondary market. The amounts obtained were translated into Brazilian reais at the exchange rate of December 31, 2021. (vii) Lease and finance lease based on IFRS 16 correspond to instruments valued at their carrying amount restated until the maturity date, and are indexed by a fixed contractual rate. Thus, the Company discloses the amount recorded as of December 31, 2021 as market value. Financial instruments referring to financial investments and borrowings and financing are classified as Level 2 in the fair value hierarchy. Considering the nature of other financial instruments, assets and liabilities, the balances recognized in the statement of financial position approximate the fair values, except for borrowings and financing, considering the maturities close to the end of the reporting date, comparison of contractual interest rates with market rates in similar operations at the end of the reporting period, their nature and maturity terms.

Key accounting estimates and ju

Key accounting estimates and judgments	12 Months Ended
	Dec. 31, 2021
Key accounting estimates and judgments	6 Key accounting estimates and judgments The preparation of the financial statements requires management to make certain judgments (except for those involving estimates) that have a significant impact on the amounts recognized based on experience and other factors deemed as relevant, which affect the values of assets and liabilities and which may present results that may differ from the actual results. The Company establishes estimates and assumptions regarding the future, which are reviewed on a timely basis. Such accounting estimates, by definition, may differ from the actual results. The effects arising from the reviews of the accounting estimates are recognized in the period in which the estimates are reviewed. 6.1 Key accounting judgments in the application of accounting policies The Company assessed the main accounting policies that involve judgments, except those that involve estimates, and concluded that none of them have a significant effect. 6.2 Main sources of uncertainties in the estimates The areas that require a higher level of judgment and have greater complexity, as well as those in which assumptions and estimates that are significant for the financial statements are disclosed as follows: (a) Allowance for doubtful accounts The Company establishes an allowance for doubtful accounts in an amount that Management considers sufficient to cover expected losses (see Note 10 (c)), based on an analysis of trade receivables, in accordance with the accounting policy stated in Notes 3.2 and 3.4. The methodology for determining such losses requires significant estimates, considering several factors, among which an evaluation of receipts historical, current economic trends, estimates of forecast write-offs, the aging of the accounts receivable portfolio and expectation of future losses. Although the Company believes that the assumptions used are reasonable, the actual results may be different. (b) Intangible assets arising from concession agreements and program contracts The Company recognizes as intangible assets those arising from concession agreements and estimates the fair value of constructions and other infrastructure works to record the cost of intangible assets, which are recognized upon the construction of the infrastructure, and it is likely that such asset will generate future economic benefits. Intangible assets under Concession Agreements, Service Agreements and Program Contracts, are amortized on a straight-line basis according to the useful life of the asset or contract period, which occurs first. Additional information on the accounting for intangible assets arising from concession agreements is described in Notes 3.9 and 15. The recognition of the fair value of the intangible assets arising from concession agreements is subject to assumptions and estimates, and the use of different assumptions may affect the accounting records. Different assumptions and future changes in the useful life of these intangible assets may have significant impacts on the result of the operations. (c) Pension plan obligations The Company sponsors a defined benefit plan and the defined contribution plan, as described in Notes 3.19 and 21. Defined pension plan obligations recognized in the statement of financial position consist of the present value of the defined benefit obligation on the reporting date less the fair value of the plan’s assets. The obligation of such benefit is calculated on an annual basis by independent actuaries, using the projected credit unit method. The present value of the defined benefit obligation is determined by discounting estimated future cash outflows, using interest rates compatible with market returns, which are denominated in the currency in which benefits will be paid and with maturity terms close to those of corresponding pension plan obligation . (d) Deferred income tax and social contribution The Company recognizes and settles taxes on income based on the results of operations calculated according to Brazilian Corporation Law, taking into consideration the provisions of the tax laws. Deferred tax assets and liabilities are recorded based on the differences between the accounting balances and the tax bases of the assets and liabilities. The Company regularly reviews the recoverability of deferred tax assets and recognizes a provision for impairment if it is probable that these assets will not be realized, based on the historic taxable income, on the projection of future taxable income and on the estimated period for reversing the temporary differences. These calculations require the use of estimates and assumptions. The use of different estimates and assumptions could result in a provision for impairment of all or a significant part of the deferred tax asset. Additional information on deferred taxes is described in Notes 3.16 and 19 . (e) Provisions The provisions for civil, labor, environmental and tax risks are created based on Notes 3.15 and 20. Judgments regarding future events may significantly differ from actual estimates and exceed the amounts provisioned. The provisions are revised and adjusted to take into consideration changes in the circumstances involved. (f) Unbilled revenue Unbilled revenue corresponds to services rendered for which readings have not been made yet. They are recognized based on monthly estimates calculated according to average billing. Additional information on revenue and accounts receivable are described in Notes 3.3 and 10 .

Cash and cash equivalents

Cash and cash equivalents	12 Months Ended
	Dec. 31, 2021
Cash and cash equivalents	7 Cash and cash equivalents Cash and cash equivalents December 31, 2021 December 31, 2020 Cash and banks 146,853 74,033 Cash equivalents 571,076 322,368 Total 717,929 396,401 Cash and cash equivalents include cash, bank deposits and high-liquidity short-term financial investments, mainly represented by repurchase agreements (accruing CDI interest rates) and CDBs, whose original maturities or intention of realization are lower than three months, which are convertible into a cash amount and subject to an insignificant risk of change in value. The average yield of cash equivalents corresponds to 96.00 95.82

Financial investments

Financial investments	12 Months Ended
	Dec. 31, 2021
Financial investments	8 Financial investments The Company has financial investments in CDB, with daily liquidity, which it does not intend to use in the next three months, as shown below: December 31, 2021 December 31, 2020 Banco BV 262,465 253,066 Banco Itaú S/A 366,906 354,296 Banco Bradesco S/A 524,791 506,136 Banco BTG Pactual S/A 367,361 354,299 Banco do Brasil S/A 911,862 1,943,349 2,433,385 3,411,146 The average yield of financial investments corresponds to 101.57 98.95

Restricted cash

Restricted cash	12 Months Ended
	Dec. 31, 2021
Restricted cash	9 Restricted cash Schedule of restricted cash December 31, 2021 December 31, 2020 Agreement with the São Paulo municipal government (i) 21,464 29,599 Brazilian Federal Savings Bank – escrow deposits (ii) 740 272 Other 6,263 5,871 28,467 35,742 (i) Refers to the amount deducted from the transfer 7.5% of the revenue earned in the municipality to the Municipal Fund for Environmental Sanitation and Infrastructure, corresponding to eventual amounts unpaid by direct management bodies, foundations and government agencies, as established in the agreement entered into with the municipal government of São Paulo; and (ii) Refers to the savings account intended to receive escrow deposits from lawsuits with final and unappealable decisions in favor of the Company, which are blocked under the contractual clause.

Trade receivables

Trade receivables	12 Months Ended
	Dec. 31, 2021
Trade receivables	10 Trade receivables (a) Financial position balances Schedule of financial position December 31, 2021 December 31, 2020 Private sector: General (i) (ii) 2,042,023 1,663,738 Agreements (iii) 514,616 398,367 2,556,639 2,062,105 Government entities: Municipal 586,810 473,201 Federal 7,869 3,859 Agreements (iii) 278,844 333,740 873,523 810,800 Wholesale customers – Municipal governments: (iv) Mogi das Cruzes 3,580 3,582 São Caetano do Sul 24,464 18,808 Total wholesale customers – Municipal governments 28,044 22,390 Unbilled supply 740,193 713,310 Subtotal 4,198,399 3,608,605 Allowance for doubtful accounts (1,280,088) (1,157,619) Total 2,918,311 2,450,986 Current 2,695,077 2,204,029 Noncurrent 223,234 246,957 2,918,311 2,450,986 (i) General customers - residential and small and mid-sized companies; (ii) Special customers - large consumers, commercial, industries, condominiums and special billing customers (fixed demand agreements, industrial waste, wells, among others); (iii) Agreements - installment payments of past-due receivables, plus monetary adjustment and interest, according to the agreements; (iv) Wholesale basis customers - municipal governments - This balance refers to invoices issued as a result of services provided to municipalities, which are responsible for distributing to, billing and charging final customers. (b) The aging of trade receivables is as follows Schedule of aging of trade receivables December 31, 2021 December 31, 2020 Current 1,896,535 1,793,104 Past-due: Up to 30 days 502,164 340,760 From 31 to 60 days 267,723 177,103 From 61 to 90 days 182,977 120,488 From 91 to 120 days 155,018 88,323 From 121 to 180 days 258,718 113,060 From 181 to 360 days 95,751 82,365 Over 360 days 839,513 893,402 Total past-due 2,301,864 1,815,501 Total 4,198,399 3,608,605 The increase in the past-due balance was mainly due to higher delinquency in the private sector. (c) Allowance for doubtful accounts Schedule of allowance for doubtful accounts December 31, 2021 December 31, 2020 December 31, 2019 Balance at beginning of the year 1,157,619 1,042,015 1,099,442 Additions 182,547 176,776 54,064 Recoveries (60,078) (61,172) (111,491) Balance at the end of the year 1,280,088 1,157,619 1,042,015 Schedule of reconciliation of estimated/historic losses of income Reconciliation of estimated/historical losses of income December 31, 2021 December 31, 2020 December 31, 2019 Write-offs (508,055) (329,512) (179,929) (Losses)/reversal with state entities - related parties (13,206) 290 (5,597) (Losses) with the private sector / government entities (182,547) (176,776) (54,064) Recoveries 60,078 61,172 111,491 Amount recorded expense (Note 29) (643,730) (444,826) (128,099) The Company does not have customers representing 10% or more of its total revenues.

Related-Party Balances and Tran

Related-Party Balances and Transactions	12 Months Ended
	Dec. 31, 2021
Related-Party Balances and Transactions	11 Related-Party Balances and Transactions (a) Accounts receivable, interest on capital payable, revenue and expenses with São Paulo Schedule of accounts receivable, interest on capital payable, revenue and expenses with Sao Paulo December 31, 2021 December 31, 2020 Accounts receivable Current: Sanitation services (i) 127,614 109,078 Allowance for losses (i) (52,333) (39,127) Reimbursement for retirement and pension benefits paid (G0): - monthly flow (payments) (ii) and (vi) 11,930 22,726 - GESP Agreement – 2015 (iv) 86,446 75,377 Total current 173,657 168,054 Noncurrent: Agreement for the installment payment of sanitation services 1,361 4,303 Reimbursement of additional retirement and pension benefits paid (G0): - GESP Agreement – 2015 (iv) 643,534 634,288 Total noncurrent 644,895 638,591 Total receivables from shareholders 818,552 806,645 Assets: Sanitation services 76,642 74,254 Reimbursement of additional retirement and pension benefits (G0) 741,910 732,391 Total 818,552 806,645 Liabilities: Interest on capital payable to related parties 275,240 116,180 Schedule of loan agreement through credit facility 2021 2020 2019 Revenue from sanitation services 522,608 501,756 556,574 Payments received from related parties (439,349) (520,881) (546,365) Payment received from reimbursement referring to Law 4,819/58 (179,787) (173,874) (152,112) (i) Sanitation services The Company provides water supply and sewage services to the São Paulo State Government and other companies related to it in accordance with usual market terms and conditions, as considered by management, except for the settlement of credits which can be made according to items (iii) of this Note. The Company recognized R$ 52,333 39,127 39,417 (ii) Reimbursement of additional retirement and pension benefits paid Refers to additional retirement and pension benefits provided for in State Law 4,819/58 ("Benefits") paid by the Company to former employees and pensioners, referred to as Go. Under the Agreement referred on item (iii) the São Paulo State recognizes its liability from charges arising from the Benefits, provided that the payment criteria set forth by the State Department of Personnel (DDPE), based on legal guidance of the Legal Consultancy of the Department of Finance and of the State Attorney General's Office (PGE). As discussed on item (vi), during the assessment of the debt due from State of São Paulo to the Company there were certain divergences in the calculation and eligibility criteria of the benefits paid by the Company on behalf of GESP. See additional information about the Go plan in Note 22 (ii). As a result of a court decision, the responsibility for making the payments returned to SABESP. (iii) GESP Agreement On December 11, 2001, the Company, the State of São Paulo (through the State Department of Finance Affairs, currently Department of Finance and Planning) and the Water and Electricity Department (DAEE), with the intermediation of the State Department of Infrastructure and Environment (former Department of Water Resources, Sanitation and Construction Works), entered into the Obligations, Payment Commitment and Other Covenants Acknowledgement and Consolidation Agreement ("GESP Agreement") for the settlement of outstanding debts between State of São Paulo and the Company related to sanitation services and to the retirement benefits. In view of the strategic importance of the Taiaçupeba, Jundiaí, Biritiba Mirim, Paraitinga and Ponte Nova reservoirs for ensuring and maintaining the Alto Tietê water volume, the Company agreed to receive them as partial repayment of the reimbursement related to the Benefits. The DAEE would transfer the reservoirs to the Company, replacing the amount owed by State of São Paulo. However, the São Paulo State Public Prosecution Office challenges the legal validity of this agreement, and its main argument is the lack of bidding and the absence of a specific legislative authorization for disposal of DAEE's assets. There is an unfavorable decision to SABESP not yet unappealable. See additional information in item (iv) below. On March 22, 2004, the Company signed the first amendment to the GESP Agreement, settling the amounts due by the State of São Paulo for water supply and sewage services provided, monetarily adjusted through February 2004; and formally authorizing the offset of amounts due by the São Paulo State Government with interest on capital declared by the Company and any other debt owed to the State of São Paulo as of December 31, 2003, monetarily adjusted through February 2004; and defining the payment conditions of the remaining liabilities of the State of São Paulo for the receipt of the water supply and sewage services. On December 28, 2007, the Company and the São Paulo State Government, represented by the Department of Finance, signed the second amendment to the terms of the original GESP Agreement, agreeing upon the payment in installments of the remaining balance of the First Amendment. In December 2012 the last installment was paid. On November 17, 2008, State of São Paulo, SABESP and DAEE signed the third amendment to the GESP Agreement, through which State of São Paulo recognized a debt balance payable to SABESP of R$ 915,251 696,283 218,967 The Company had not recognize in its Financial Statements the amount receivable of R$ 696,283 The third amendment also provides for the regularization of the monthly flow of benefits. While SABESP is responsible for the monthly payments, the São Paulo State shall reimburse the Company based on the criteria identical to those applied when determining the Undisputed Amount. Should there be no preventive court decision, the State will directly assume the monthly payment flow of the portion deemed as undisputed. (iv) GESP Agreement - 2015 On March 18, 2015, the Company, the State of São Paulo and the Department of Water and Electricity (DAEE), and the Sanitation and Water Resources Department as the intervening party, entered into a Term of Agreement in the amount of R$ 1,012,310 696,283 316,027 The Principal Amount will be paid in 180 installments, as follows: The first 24 installments were settled by immediately transferring 2,221,000 87,174 The amount of R$ 609,109 Considering the lawsuit which objects the possibility of transferring the reservoirs is pending final and unappealable court decision, the agreement also provides for the following situations: If transfer is possible and the Reservoirs are effectively transferred to SABESP and registered at the notary’s office, SABESP will reimburse to the State the amounts paid in replacement of Reservoirs (Principal Amount) in 60 monthly installments adjusted by IPCA until the date of payment of each installment; and If the transfer of Reservoirs is not possible, the São Paulo State will pay to SABESP, in addition to the Principal Amount, the inflation adjustment credit of R$ 316,027 As of December 31, 2021, the balance receivable totaled R$ 86,446 75,377 643,534 634,288 (v) Disputed Amounts As mentioned before, on November 17, 2008 the Company and the São Paulo State signed the third amendment to the GESP Agreement, when the reimbursements called disputed and undisputed were quantified. The amendment established the efforts to calculate the so-called Disputed Reimbursement of the Benefits. Under the fourth clause of the amendment, the Disputed Reimbursement represents the difference between the Undisputable Reimbursement and the amount actually paid by the Company as pension benefits and pensioners set out in Law 4,819/58, for which, the Company understands, the State of São Paulo is originally liable, but paid by SABESP under a court order. By entering into the third amendment, the State's Legal Representative (PGE) agreed to reassess the differences that gave rise to the Disputed Amount of benefits set out in Law 4,819/58. At the time, the expectation was based on the willingness of the PGE to reanalyze the issue and the implied right of the Company to the reimbursement, including based on opinions from outside legal advisors. However, the latest opinions issued by the PGE and received on September 4 and 22, 2009 and January 4, 2010, refute the reimbursement of previously defined as Disputed Amount. Even though the negotiations with the State are still in progress, it is not possible to assure that the Company will recover the disputed receivables without dispute. As part of the actions intended to recover the receivables that management considers due by the State, related to discrepancies in the reimbursement of the pension benefits paid by the Company, SABESP: (i) on March 24, 2010, reported to the controlling shareholder the official letter approved by the executive committee, proposing that the matter be discussed at the São Paulo Stock Exchange (B3) Arbitration Chamber; (ii) in June 2010, presented to Department of Finance a proposal to solve the outstanding items, such proposal was not accepted; (iii) on November 9, 2010, filed a judicial action against the State of São Paulo pleading the entire reimbursement related to employee benefits set out in Law 4,819/58 to finalize the discussion between the Company and State of São Paulo. Despite the legal action, the expectation of which is a possible gain, the Company will persist to obtain an agreement with GESP since the management believes that it is the best course of action to the Company and to its shareholders than waiting until the end of the lawsuit. As of December 31, 2021 and 2020, the disputed amounts between SABESP and State of São Paulo, corresponding to additional retirement and pension benefits paid (Law 4,819/1958), totaled R$ 1,375,137 1,281,409 (vi) Actuarial Liability The Company also recognized an actuarial liability corresponding to additional retirement and pension benefits paid to employees, retired employees and pensioners of Plan G0. As of December 31, 2021 and 2020, the amounts corresponding to the actuarial liability totaled R$ 2,192,062 2,549,541 (b) Use of Reservoirs – EMAE Empresa Metropolitana de Águas e Energia S.A. - EMAE planned to receive for the credit and obtain financial compensation for alleged past and future losses in electricity generation arising from water collection, and compensation for costs already incurred and to be incurred with the operation, maintenance and inspection of the Guarapiranga and Billings reservoirs used by SABESP in its operations. On October 28, 2016, the Company entered into an agreement based on a Private Transaction Agreement and Other Adjustments to settle the disputes involving the two companies and the SABESP will continue using the reservoirs. As of December 31, 2021, the Company recorded R$ 7,956 88,264 17,255 73,660 (c) Agreements with reduced tariffs for State Entities that join the Rational Water Use Program (PURA) The Company has signed agreements with government entities related to the São Paulo State Government that benefit them with a reduction of 25% in the tariff of water supply and sewage services when they are not in default. These agreements provide for the implementation of the rational water use program, which takes into consideration the reduction in water consumption. (d) Guarantees The São Paulo State provides guarantees for some borrowings and financing of the Company and does not charge any fee with respect to such guarantees, see Note 17. (e) Personnel assignment agreement among entities related to the São Paulo State Government The Company has personnel assignment agreements with entities related to the São Paulo State Government, whose expenses are fully charged. In 2021, the expenses related to personnel assigned by SABESP to other state government entities amounted to R$ 734 2,108 4,881 In 2021, there were not expenses related to personnel assigned by other entities to SABESP (In 2020 and 2019, the expenses related to personnel assigned by other entities to SABESP were R$ 13 139 (f) Non-operating assets As of December 31, 2021 and 2020, the Company had an amount of R$ 3,613 (g) SABESPREV The Company sponsors a private defined benefit pension plan (G1 Plan), which is operated and administered by SABESPREV. The net actuarial liability recognized as of December 31, 2021 amounted to R$ 129,600 319,053 (h) Compensation of Management Key Personnel and Fiscal Council The compensation of the Executive Officers, members of the Audit Committee and Boards of Directors and Fiscal Councils of the Companies controlled by the São Paulo State complies with the guidelines of the State Capital Defense Council (CODEC) and is defined at the Annual Shareholders’ Meeting, as per article 152 of Brazilian Corporation Law. CODEC defines that the proposal for global and individual compensation of the statutory bodies for publicly held companies listed in B3’s Novo Mercado segment, controlled by the State, must be prepared by the Board of Directors under the Company’s Bylaws, within the scope of the Institutional Compensation Policy and submitted for approval of the Annual Shareholders’ Meeting. In addition to the monthly compensation, the members of the Board of Directors, Fiscal Council and Executive Board receive annual reward equivalent to a monthly fee, calculated on a prorated basis in December of each year. The purpose of this reward is to define a compensation similar to the Christmas bonus paid to the Company’s registered employees, given that the relationship of Management with the Company has a statutory nature. Benefits paid to Executive Officers only - meal vouchers, food vouchers, healthcare, private pension, annual rest (with the characteristic of paid leave of thirty (30) calendar days, with additional payment corresponding to one third of the monthly fees for such rest), and FGTS. SABESP pays bonuses for purposes of compensation of its Executive Officers, in accordance with the guidelines of the São Paulo State, such as a motivation policy, provided that the Company actually calculates quarterly, semi-annual and annual profits, and distributes mandatory dividends to shareholders, even if in the form of interest on capital. Annual bonuses cannot exceed six times Management’s monthly compensation or 10 % of the interest on capital paid by the Company, prevailing the shortest amount. Expenses related to the compensation of the members of the Fiscal Council appointed by the controlling shareholder and Management members totaled R$ 6,369 6,426 Additional amounts of R$ 1,440 1,439 (i) Loan agreement through credit facility The Company holds interest in certain Special Purpose Entities (SPEs), not holding the majority interest but with cast vote and power of veto in some issues, with no ability to use such power of veto in a way to affect returns over investments. Therefore, these SPEs are considered for accounting purposes as joint arrangements. Aquapolo Ambiental The Company entered into a loan agreement through credit facility with the SPE Aquapolo Ambiental S/A to finance the operations of this company, until the borrowings and financing requested with financial institutions is granted. As of December 31, 2021, the balance of principal and interest of this agreement totaled R$ 11,884 11,021 9,420 23,866 . The loan agreement originally matured on April 30, 2015 but was extended to October 30, 2015 and on November 25, 2015 a new amendment changed the payment schedule for three annual installments, the first of which maturing on December 30, 2021 and the last on December 30, 2023. Águas de Andradina The Company entered into a loan agreement through credit facility with the SPE Águas de Andradina S/A to finance the operations of this company. As of December 31, 2021, the balance of principal and interest of this agreement totaled R$ 34 1,009 . This agreement was signed on August 17, 2021. The principal with the readjustment, accrued interest and any taxes levied thereon, shall be fully reimbursed by the Borrower, to SABESP, until August 31, 2025. (j) FEHIDRO In April 2021, the Company entered into three financing agreements within the scope of the State Water Resources Fund – FEHIDRO. The funds will be allocated to the execution of sanitary sewage works and services in the municipalities of São Paulo, Itapecerica da Serra and Vargem Grande Paulista. The total investment amount is R$ 10.8 million 8.7 million 2.1 million 3.00

Investments

Investments	12 Months Ended
	Dec. 31, 2021
Investments	12 Investments The Company holds interest in certain Special Purpose Entities (SPE). Although SABESP has no majority shares of its investees, the shareholders’ agreement provides for the power of veto in certain management issues, however, with no ability to use such power of veto in a way to affect the returns over the investments, indicating participating shared control (joint venture – IFRS 11). The Company holds interest recognized by the equity accounting in the following investees: (a) Sesamm As of August 15, 2008, Sesamm – Serviços de Saneamento de Mogi Mirim S/A was incorporated for a period of 30 years from the date the concession agreement with the municipality for the purpose of providing complementary services to the sewage diversion system and implementing and operating sewage treatment system in the municipality of Mogi Mirim, including the disposal of solid waste. Sesamm's capital as of December 31, 2021, totaled R$ 19,532 19,532,409 36 64 The operations initiated in June 2012. (b) Águas de Andradina As of September 15, 2010, the Company, Águas de Andradina S.A. was incorporated, with indefinite term, for the purpose of providing water supply and sewage services to the municipality of Andradina. As of December 31, 2021, the capital of Águas de Andradina totaled R$ 17,936 17,936,174 30 70 The Company pledges as guarantee 100% of its shares in Águas de Andradina as a counter guarantee for the issuance of Letters of Guarantee with BNDES. The operations initiated in October 2010. (c) Águas de Castilho As of October 29, 2010, the Company, Águas de Castilho, was incorporated for the purpose of providing water supply and sewage services to the municipality of Castilho. As of December 31, 2021, the company’s capital was R$ 2,785 2,785,225 30 70 The Company pledges as guarantee 100% of its shares in Águas de Castilho as a counter guarantee for the issuance of Letters of Guarantee with BNDES. The operations initiated in January 2011. (d) Attend Ambiental As of August 23, 2020, Attend Ambiental S/A was incorporated with the purpose of implementing and operating a pre-treatment station of non-domestic effluents and sludge transportation in the metropolitan region of São Paulo, as well as the development of other related activities and the creation of similar infrastructures in other locations in Brazil and abroad. As of December 31, 2021, the capital totaled R$ 37,677, and was represented by 37,677,245 registered common shares without a par value. SABESP holds a 45% interest and Estre 55%. The operations initiated in December 2014. (e) Aquapolo Ambiental S/A. As of October 8, 2009, the Company, Aquapolo Ambiental S.A., was incorporated for the purpose of producing, providing and trading reused water for Quattor Química S.A., Quattor Petroquímica S.A., Quattor Participações S.A. and other companies comprising the Petrochemical Complex of Capuava and the metropolitan region of São Paulo. As of December 31, 2021, the capital of Aquapolo totaled R$ 36,412 42,419,045 The Company pledges as guarantee to the loan acquired through the issuance of debentures, 100% of its shares in Aquapolo Ambiental S/A. The operations initiated in October 2012. (f) Paulista Geradora de Energia As of April 13, 2015, the Company acquired shares from Empresa Paulista Geradora de Energia S/A - PGE, jointly with Servtec Investimentos e Participações Ltda ("Servtec) and Tecniplan Engenharia e Comércio Ltda ("Tecniplan"), which operational purpose is the implementation and commercial exploration of water potential in small hydroelectric power plants (PCHs), located at the Guaraú and Vertedouro Cascata Water Treatment Stations. As of December 31, 2020, the capital of Paulista Geradora de Energia was R$ 8,679 8,679,040 25 37.5 37.5 As of December 31, 2021, operations had not initiated yet. Below is a summary of the investees’ financial information and SABESP’s equity interest: Schedule of the investees' financial statements and equity interest Company Equity Dividends distributed Profit (loss) for the year 2021 2020 2019 2021 2021 (*) 2020 2019 Sesamm 58,421 51,514 45,923 (2,152) 9,059 — 7,332 4,418 Águas de Andradina 29,591 29,576 30,065 (2,320) 2,424 (89) 778 7,271 Águas de Castilho 9,384 8,533 7,242 (592) 1,428 15 1,613 1,767 Saneaqua Mairinque¹ — 4,013 4,783 — — — (770) (871) Attend Ambiental 23,493 11,409 7,486 — 4,701 7,383 3,923 (18,217) Aquapolo Ambiental 58,172 41,903 37,772 (9,000) 25,269 — 19,131 16,283 Paulista Geradora de Energia 6,153 6,692 7,144 — (539) — (452) (481) Company Investments Dividends distributed Other Comprehensive Income Reclassification Equity in the earnings of subsidiaries Interest percentage 2021 2020 2021 2020 2020 2021 (*) 2020 2019 2021 2020 2019 Sesamm 21,032 18,546 (775) — — 3,261 — 2,640 1,591 36 36 36 Águas de Andradina 8,877 8,873 (696) — — 727 (27) 233 2,181 30 30 30 Águas de Castilho 2,815 2,560 (178) — — 429 4 485 529 30 30 30 Saneaqua Mairinque² — — — 17 (1,203) — — (248) (262) 4,6 4,6 30 Attend Ambiental 10,572 5,134 — — — 2,116 3,322 1,765 (8,198) 45 45 45 Aquapolo Ambiental 28,504 20,532 (4,410) — — 12,382 — 9,374 7,979 49 49 49 Paulista Geradora de Energia 1,538 1,673 — — — (135) — (113) (119) 25 25 25 Total 73,338 57,318 (6,059) 17 (1,203) 18,780 3,299 14,136 3,701 Other investments 6,099 6,099 Overall total 79,437 63,417 (*) Refer to changes in the equity of investees, as their financial statements for the year ended December 31, 2020 were issued, including some adjustments, after the Company’s financial statements. (¹) The amounts presented for 2020 refer to July 31, 2020. (²) On August 20, 2020, the investee Saneaqua Mairinque held an Extraordinary Shareholders' Meeting that approved a capital increase in the amount of R$ 21,944 17,178,988 5,734

Investment properties

Investment properties	12 Months Ended
	Dec. 31, 2021
Investment properties	13 Investment properties Schedule of investment properties December 31, 2020 Write-offs and disposals Depreciation December 31, 2021 Investment properties 46,274 (100) (48) 46,126 December 31, 2019 Transfers Depreciation December 31, 2020 Investment properties 47,562 (1,240) (48) 46,274 December 31, 2018 Transfers Depreciation December 31, 2019 Investment properties 47,620 (9) (49) 47,562 As of December 31, 2021 and 2020, the market value of these properties was approximately R$ 386,000 383,000

Contract assets

Contract assets	12 Months Ended
	Dec. 31, 2021
Contract assets	14 Contract assets Schedule of contract assets December 31, 2020 Additions (i) Transfers Transfers of works to intangible assets (ii) December 31, 2021 (iii) Total contract assets 7,969,164 4,759,789 2,412 (4,181,263) 8,550,102 (i) The largest additions of the period are located in the municipalities of São Paulo, Guarulhos and Praia Grande, in the amounts of R$ 2,419 million, R$ 180 million and R$ 158 million, respectively. (ii) The largest transfers of the period are located in the municipalities of São Paulo, Itaquaquecetuba and São Bernardo do Campo, in the amounts of R$ 2,270 million, R$ 199 million and R$ 180 million, respectively. (iii) The largest works are located in the municipalities of São Paulo, Praia Grande and São Bernardo do Campo, in the amounts of R$ 3,955 million, R$ 634 million and R$ 407 million, respectively. As of December 31, 2021, contract assets include leases recognized before December 31, 2019 in accordance with IAS 17 amounting to R$ 276,893 276,893 December 31, 2019 Additions (i) Transfers Transfers of works to intangible assets (ii) December 31, 2020 (iii) Total contract assets 7,617,714 3,984,158 55,706 (3,688,414) 7,969,164 December 31, 2018 Additions Write-offs Transfers Transfers of works to intangible assets December 31, 2019 Total contract assets 7,407,948 3,532,283 (4,910) 10,710 (3,328,317) 7,617,714 (a) Capitalization of interest and other finance charges In 2021, the Company capitalized interest and inflation adjustment, including related foreign currency exchange effects in the contract asset, totaling R$ 300,792 238,330 233,251 (b) Construction margin The Company is primarily responsible for the construction and installation of the concession infrastructure related to the concession, using own efforts or hiring outsourcing services, receiving the risks and benefits. Accordingly, the Company recognizes revenue from construction service corresponding to the cost of construction increased by gross margin. Generally, the constructions related to the concessions are performed by third parties, in such case, the margin of the Company is lower, normally, to cover eventual administration costs, and the responsibility of the primary risk. In 2021 and 2020 the margin was 2.3%. Construction margin for 2021, 2020 and 2019 were R$ 98,402 86,477 65,172 (c) Expropriations As a result of the construction of priority projects related to water and sewage systems, the Company was required to expropriate third-parties' properties, and the owners of these properties will be compensated either amicably or through courts. The costs of such expropriations are recorded in contract assets during construction. In 2021 and 2020, the total referring to expropriations was R$ 67,714 33,136

Intangible assets

Intangible assets	12 Months Ended
	Dec. 31, 2021
Intangible assets	15 Intangible assets (a) Statement of financial position details December 31, 2021 December 31, 2020 Cost Accumulated amortization Net Cost Accumulated amortization Net Intangible right arising from: Concession agreements – equity value 696,728 (205,671) 491,057 671,904 (188,129) 483,775 Concession agreements – economic value 1,497,968 (816,527) 681,441 1,446,261 (711,596) 734,665 Program contracts 24,804,170 (7,652,149) 17,152,021 23,160,119 (6,799,812) 16,360,307 Program contracts – commitments 1,709,757 (391,800) 1,317,957 1,709,757 (338,834) 1,370,923 Services contracts – São Paulo 22,834,803 (6,676,032) 16,158,771 20,579,676 (5,707,072) 14,872,604 Software license of use 1,133,833 (535,099) 598,734 978,085 (437,460) 540,625 Right of use – other assets 173,715 (69,862) 103,853 141,782 (99,106) 42,676 Total 52,850,974 (16,347,140) 36,503,834 48,687,584 (14,282,009) 34,405,575 (b) Changes December 31, 2020 Addition Transfer of contract assets Transfers Write-offs and disposals Amortization December 31, 2021 Intangible right arising from: Concession agreements – equity value (*) 483,775 — 24,656 467 (148) (17,693) 491,057 Concession agreements – economic value 734,665 — 52,275 (14) (242) (105,243) 681,441 Program contracts (*) 16,360,307 17,690 1,640,733 13,744 (8,840) (871,613) 17,152,021 Program contracts – commitments 1,370,923 — — — — (52,966) 1,317,957 Services contracts – São Paulo 14,872,604 14,950 2,307,851 (13,827) (13,745) (1,009,062) 16,158,771 Software license of use 540,625 — 155,748 — — (97,639) 598,734 Right of use – Other assets 42,676 140,321 — — (4,103) (75,041) 103,853 Total 34,405,575 172,961 4,181,263 370 (27,078) (2,229,257) 36,503,834 (*) As of December 31, 2021, intangible assets include leases recognized before December 31, 2018 in accordance with IAS 17 amounting to R$ 245,681 65,012 180,669 269,561 76,454 193,107 December 31, 2019 Addition Contract renewal Transfer of contract assets Transfers Write-offs and disposals Amortization December 31, 2020 Intangible right arising from: Concession agreements – equity value (*) 1,494,853 1 (1,031,830) 47,154 1,440 (858) (26,985) 483,775 Concession agreements – economic value 712,852 — — 113,320 (1,403) (42) (90,062) 734,665 Program contracts (*) 13,819,700 303,472 1,031,830 2,075,268 (51,570) (5,423) (812,970) 16,360,307 Program contracts – commitments 1,364,875 58,323 — — — — (52,275) 1,370,923 Services contracts – São Paulo 14,390,763 20,940 — 1,382,656 (23,645) (9,990) (888,120) 14,872,604 Software license of use 471,706 — — 70,016 78,169 — (79,266) 540,625 Right of use – Other assets 70,698 28,549 — — — — (56,571) 42,676 Total 32,325,447 411,285 — 3,688,414 2,991 (16,313) (2,006,249) 34,405,575 (*) As of December 31, 2020, intangible assets includes leases recognized before December 31, 2018 in accordance with IAS 17 amounting to R$ 269,561 76,454 193,107 292,824 87,266 205,558 December 31, 2018 First-time adoption of IFRS 16 Addition Contract renewal Transfer to indemnities receivable Transfer of contract assets Transfers Write-offs and disposals Amortization December 31, 2019* Intangible right arising from: Concession agreements – equity value (*) 4,073,344 — 2 (2,690,660) (4,345) 131,809 76,804 (8,311) (83,790) 1,494,853 Concession agreements – economic value 1,232,009 — 2,034 (532,173) — 89,041 1,956 (569) (79,446) 712,852 Program contracts (*) 8,777,929 — 1,338,443 3,223,773 — 970,534 137,283 (10,312) (617,950) 13,819,700 Program contracts – commitments 1,079,551 — 331,328 — — — — — (46,004) 1,364,875 Services contracts – São Paulo 13,391,452 — 3,867 (940) — 2,054,940 (228,583) (20,739) (809,234) 14,390,763 Software license of use 458,175 — — — — 81,993 (991) — (67,471) 471,706 Right of use – Other assets — 64,955 48,278 — — — — — (42,535) 70,698 Total 29,012,460 64,955 1,723,952 — (4,345) 3,328,317 (13,531) (39,931) (1,746,430) 32,325,447 (*) As of December 31, 2019, intangible assets includes leases recognized before December 31, 2018 in accordance with IAS 17 amounting to R$ 292,824 315,717 98,077 217,640 As of June 30, 2020, a contract was signed for the provision of treatment services and final disposal of solid waste and collection of garbage tax in the Municipality of Diadema for 40 years. In order to reach the best operationalization format, treatment services and final disposal of solid waste are in the study phase and, based on contractual provision, are subject to a partnership between SABESP and a private party, which will occur by means of a public call. (c) Intangible arising from concession agreements The Company operates public utility service concession agreements for water supply and sewage services mostly based on agreements that set out rights and obligations relative to the exploration of assets related to the public utility service (See Note 3.9 (a)). The agreements provide for the return of the assets to the concession grantor at the end of the concession period. As of December 31, 2021 and 2020, the Company operated in 375 372 The services provided by the Company are billed at a price regulated and controlled by São Paulo State Sanitation and Energy Regulatory Agency (ARSESP). Intangible rights arising from concession agreements include: (i) Concession agreements – equity value These refer to municipalities assumed until 2006, except for the municipalities assumed by economic value through assets valuation report prepared by independent experts. The amortization of assets is calculated according to the straight-line method, which considers the assets useful life. (ii) Concession agreements – economic value From 1999 through 2006, the negotiations for new concessions were conducted on the basis of the economic and financial result of the transaction, determined in a valuation report issued by independent appraisers. The amount determined in the related contract, after the transaction is closed with the municipal authorities, realized through the subscription of the Company's shares or in cash, is recorded as "concession agreements" and amortized over the period of the related concession (usually 30 years). As of December 31, 2021 and 2020 there were no amounts pending related to these payments to the municipalities. Intangible assets are amortized on a straight-line basis over the period of the concession agreements or for the useful lives of the underlying assets, whichever is shorter. (iii) Program contracts These refer to the renewal of contracts previously referred to as concession agreements whose purpose is to provide sanitation services. The amortization of the assets acquired until the dates of signatures of the program contracts is calculated according to the straight-line method, which considers the assets’ useful lives. Assets acquired or built after the signature dates of program contracts are amortized during the contracted period (mostly, 30 years) or during the useful lives of underlying assets, whichever is shorter. (iv) Program contracts - Commitments After the enactment of the regulatory framework in 2007, renewals of concessions started to be made through of program contracts. In some of these program contracts, the Company undertook the commitment to financially participate in social and environmental actions. The assets built within the program contracts are recorded as intangible assets and are amortized by the straight-line method in accordance with the duration of the program contract (mostly, 30 years). As of December 31, 2021 and 2020, the amounts not yet disbursed were recorded under “program contract commitments”, in current liabilities, totaling R$ 77,652 162,541 44,995 68,939 (v) Services agreement with the Municipality of São Paulo On June 23, 2010, the Company entered into an agreement with the State of São Paulo and the Municipality of São Paulo to regulate the provision of water and sewage services in the municipality of São Paulo for a 30-year period, which is extendable for an another 30-year period. Also on June 23, 2010, an agreement was signed between the state and municipal government, and SABESP and the Sanitation and Energy Regulatory Agency of the State of São Paulo (“ARSESP”) are the consenting and intervening parties, whose main aspects are the following: 1. The State and the Municipality of São Paulo grant to SABESP the right to explore the sanitation services in the capital of the State of São Paulo, which consists of the obligation to provide such service and charge the respective tariff for this service; 2. The State and the Municipality sets forth ARSESP as the agency responsible for regulating the tariff, controlling and monitoring the services. 3. The evaluation model of the contract was the discounted cash flow, which considered the financial and economic sustainability of SABESP’s operations in the metropolitan region of São Paulo; 4. All operating costs, taxes, investments and the opportunity cost of investors and the creditors of SABESP’s were considered in the cash flow analysis; 5. The agreement provides for investments established in the agreement comply with the minimum of 13% of the gross revenue from the municipality of São Paulo, net of the taxes on revenues. Investment plans referring to SABESP’s execution shall be compatible with the activities and programs foreseen in the state, municipal sanitation plans, and where applicable, the metropolitan plan. The investment plan is not definite and will be revised by Managing Committee every four years, especially as to investments to be made in the following period; 6. The payment related to the Municipal Fund of Environmental Sanitation and Infrastructure to be applied in the sanitation service within the municipality must be recovered through the tariffs charges. Such payment represents 7.5 7. The opportunity cost of the investors and the creditors was established by the Weighted Average Cost of Capital (WACC) methodology. The WACC was the interest rate used to discount the cash flow of the operation; and 8. The agreement considers the recovery of net assets in operation, preferably evaluated through equity valuation or carrying amount monetarily restated, as defined by ARSESP. In addition, the agreement provides for the remuneration of investments to be made by SABESP, so that there is no residual value at the end of the agreement. Referring to the recovery through tariff, mentioned in item 6 above, of transfer to the Municipal Fund of Environmental Sanitation and Infrastructure, ARSESP issued in April 2013, the Resolution no. 413, postponing the application of Resolution no. 407 until the conclusion of the tariff revision process, the transfer to the bill of services of amounts referring to the municipal charges which were stipulated in Resolution no. 407. The postponement to apply Resolution no. 407 was due to a request by the São Paulo State Government to analyze, among other things, methods to reduce the impact on consumers. As of April 18, 2014, ARSESP Resolution no. 484 was published with the final results of SABESP’s Tariff Revision, however, both the São Paulo Municipal Government, through Official Letter no. 1,309/2014-SGM/GAB and the São Paulo State Government through a petition filed by the São Paulo State Office, through the Official Letter ATG/Official Letter no. 092/2014-CC, requested a postponement of the effects of ARSESP Resolution no. 413, published in the São Paulo State Official Gazette on March 20, 2013, until the conclusion of the revision of the Agreement entered into between the São Paulo Municipal Government, the São Paulo State and SABESP. On May 9, 2018, ARSESP announced the final result of the Second Ordinary Tariff Revision and, as of this revision cycle, ARSESP has been passing-on on the tariffs up to 4% of municipal revenue, which is transferred from SABESP to the Municipal Fund for Environmental Sanitation and Infrastructure legally created. Under the Second Ordinary Tariff Revision, concluded in May 2018, the only contract providing for that transfer and meeting the requirements of ARSESP was the one executed with the municipality of São Paulo. Accordingly, 4% of the funds transferred to the Municipal Fund for Environmental Sanitation and Infrastructure of São Paulo were passed-on to the tariffs of the tariff cycle ended in April 2021. The Municipal Government of São Paulo and the Company have not reached an agreement to define the percentage of the Municipal Fund for Environmental Sanitation and Infrastructure transfer to the tariffs charged by the Company in the Municipality of São Paulo, which led to the filing by the municipality claiming the percentage provided for in the contract between the parties. The municipality required the suspension of the lawsuit and SABESP has not yet been summoned. At the time of execution of the agreement, the municipality of São Paulo and the Company did not conclude an agreement to settle the pending financial issues existing, related to the rendering water supply and sewage services to the properties of the Municipality, and for that reason, the Company filed lawsuits for collection of the aforementioned amounts, which remain in progress and are recorded under allowance for doubtful accounts. The agreement represents 44.45 44.58 (d) Public-Private Partnership - PPP SABESP carries out operations related to the PPPs mentioned below. These operations and their respective obligations and guarantees are supported by agreements executed according to Law 11,079/2004. Alto Tietê Production System The Company and the special purpose entity CAB-Sistema Produtor Alto Tietê S/A (currently SPAT Saneamento S/A), formed by Galvão Engenharia S.A. and Companhia Águas do Brasil – Cab Ambiental, signed in June 2008 the contract of Public-Private Partnership of Alto Tietê production system. The service contract is valid for 15 years and has the purpose of expanding the capacity of the Taiaçupeba Water Treatment Station, from 10 thousand to 15 thousand of liters per second. The operation started in October 2011. As of December 31, 2021 and 2020, the carrying amounts related to this PPP recorded in intangible assets were R$ 269,062 287,645 SABESP monthly transfers funds from tariffs collected for services provided to the SPE CAB Sistema Produtor Alto Tietê S/A , in the amount of R$ 13,265 The guarantee has been effective since the beginning of the operation and will be valid until the end, termination, intervention, annulment or caducity of the Administrative Concession, or other events of extinction provided for in the Concession Agreement or in the legislation applicable to administrative concessions, including in the event of bankruptcy or dissolution of the SPE. São Lourenço Production System In August 2013, the Company and the special purpose entity Sistema Produtor São Lourenço S/A, formed by of Construções e Comércio Camargo Corrêa S/A and Construtora Andrade Gutierrez S/A, signed the Public-Private Partnership agreements of the São Lourenço Production System. In May 2018, the control of SPE Sistema Produtor São Lourenço S/A was transferred to CGGC Construtora do Brasil Ltda, previously formed of Construções e Comércio Camargo Corrêa S/A and Construtora Andrade Gutierrez S/A. The objective of the contract is: a) the construction of a water production system, mainly consisting of a water pipeline connecting Ibiúna to Barueri, a water collection station in Ibiúna, a water treatment station in Vargem Grande Paulista and water reservoirs; and b) the provision of services for a 25-year term, aiming at rendering services to operate the dehydration system, drying and final disposal of sludge, maintenance and works of the São Lourenço Production System. The works started in April 2014 and The São Lourenço Production System (SPSL) PPP started operating on July 10, 2018. Since the beginning of operations, the Company monthly transfers funds from tariffs collected for services provided to the SPE Sistema Produtor São Lourenço S/A, in the amount of R$ 36,519 The guarantee will become effective as of the beginning of the system’s appropriate operation, duly accepted by SABESP, valid until the occurrence of any of the following events, whichever occurs first: (i) the original payment date of the last installment of interest / amortization of the principal taken out by the SPE to execute the works; (ii) the end, termination, intervention, annulment, caducity of the Administrative Concession, or other extinction events provided for in the Concession Agreement or in the law applicable to administrative concessions, including bankruptcy or extinction of the SPE. As of December 31, 2021 and 2020, the carrying amounts recorded in the Company’s intangible assets, related to this PPP, amounted to R$ 2,895,798 3,065,445 7.80 The obligations assumed by the Company as of December 31, 2021 and 2020 are shown in the table below: December 31, 2021 December 31, 2020 Current liabilities Noncurrent liabilities Total liabilities Current liabilities Noncurrent liabilities Total liabilities Alto Tietê 69,442 102,873 172,315 59,429 149,726 209,155 São Lourenço 73,315 2,814,555 2,887,870 70,778 2,895,340 2,966,118 Total 142,757 2,917,428 3,060,185 130,207 3,045,066 3,175,273 (e) Amortization of intangible assets The amortization average rate totaled 4.9 4.7 4.2 . (f) Software license of use The software license of use is capitalized based on the costs incurred to acquire software and make them ready for use. As of April 10, 2017, the Company implemented the Integrated Business Management System (Enterprise Resource Planning – SAP ERP), which includes the administrative/financial module. The implementation of the commercial module is in progress. The implementation of the commercial module Net Suíte system was concluded on October 13, 2021. (g) Right of use Nature December 31, 2021 December 31, 2020 Leases - Contract Assets 276,893 276,893 Leases - Concession Agreements and Program Contracts Cost 405,446 405,426 Accumulated amortization (159,765) (135,865) (=) Net 245,681 269,561 Other assets (*) Vehicles 142,003 115,208 Properties 6,570 15,508 Equipment 9,841 4,541 Other assets 15,301 6,525 Accumulated amortization (69,862) (99,106) (=) Net 103,853 42,676 Right of use 626,427 589,130 (*) From January to December 2021, costs and accumulated totaling R$ 108,406 Lease liability corresponds to total future fixed lease payments, adjusted to present value, considering an incremental rate on borrowings. For further information, see Note 17. The table below shows the impact in the income statements: Impact in the income statement December 31, 2021 December 31, 2020 December 31, 2019 Right-of-use amortization (75,041) (79,834) (65,413) Financial result – interest expenses (68,730) (62,956) (54,791) Short-term and low-value lease expenses (22,467) (13,845) (51,855) Decrease of the income of the year (166,238) (156,635) (172,059) (h) Performance Agreements SABESP has performance agreements for the construction of assets, in which the contractor is paid for the delivery of results, not only for the execution of the construction works. The performance agreements have basically three phases: (i) implementation of the scope - construction of the asset; (ii) calculation of the performance of the asset built; and (iii) payment of fixed installments. SABESP monitors the performance of the agreement and recognizes the assets when future economic benefits are generated for the Company so that costs can be reliably measured. The performance value is part of the asset’s cost, as it has better performance and, consequently, generates additional future economic benefits for the Company. The limit to be paid to the supplier corresponds to 120 As of December 31, 2021 and 2020, the accounting balances of these agreements recorded in contract asset were R$ 737,657 306,738 871,488 265,940 .

Property, plant and equipment

Property, plant and equipment	12 Months Ended
	Dec. 31, 2021
Property, plant and equipment	16 Property, plant and equipment (a) Statement of financial position details Schedule of statement of financial position details December 31, 2021 December 31, 2020 Cost Accumulated depreciation Net Annual Depreciation average rate Cost Accumulated depreciation Net Annual Depreciation average rate Land 94,213 — 94,213 — 94,213 — 94,213 — Buildings 86,703 (41,205) 45,498 2.1 86,860 (41,513) 45,347 2.1 Equipment 397,782 (282,628) 115,154 15.1 372,103 (271,087) 101,016 14.8 Transportation equipment 10,434 (7,962) 2,472 9.9 10,319 (7,350) 2,969 9.9 Furniture and fixtures 36,561 (14,482) 22,079 6.7 31,232 (13,813) 17,419 6.7 Other 11,982 (241) 11,741 5.0 7,618 (331) 7,287 4.9 Total 637,675 (346,518) 291,157 11.1 602,345 (334,094) 268,251 11.2 (b) Changes Schedule of changes in property, plant, and equipment December 31, 2020 Additions Transfers Write-offs and disposals Depreciation December 31, 2021 Land 94,213 — — — — 94,213 Buildings 45,347 3,181 (1,965) (5) (1,060) 45,498 Equipment 101,016 38,807 (3,398) (365) (20,906) 115,154 Transportation equipment 2,969 97 69 — (663) 2,472 Furniture and fixtures 17,419 4,477 1,647 (206) (1,258) 22,079 Other 7,287 3,719 865 — (130) 11,741 Total 268,251 50,281 (2,782) (576) (24,017) 291,157 December 31, 2019 Additions Transfers Write-offs and disposals Depreciation December 31, 2020 Land 92,962 — 1,251 — — 94,213 Buildings 41,705 5,430 (713) — (1,075) 45,347 Equipment 152,273 26,055 (49,188) (174) (27,950) 101,016 Transportation equipment 1,984 298 1,351 — (664) 2,969 Furniture and fixtures 18,219 4,087 (3,712) (103) (1,072) 17,419 Other 7,250 6,537 (6,446) — (54) 7,287 Total 314,393 42,407 (57,457) (277) (30,815) 268,251 December 31, 2018 Additions Transfers Write-offs and disposals Depreciation December 31, 2019 Land 92,979 — (17) — — 92,962 Buildings 40,125 3,497 15 — (1,932) 41,705 Equipment 116,086 63,216 3,149 (429) (29,749) 152,273 Transportation equipment 3,473 308 (1,117) (2) (678) 1,984 Furniture and fixtures 13,578 5,266 734 (162) (1,197) 18,219 Other 1,371 5,872 66 — (59) 7,250 Total 267,612 78,159 2,830 (593) (33,615) 314,393

Borrowings and financing

Borrowings and financing	12 Months Ended
	Dec. 31, 2021
Borrowings and financing	17 Borrowings and financing Schedule of borrowings and financing outstanding Borrowings and financing outstanding balance December 31, 2021 December 31, 2020 Financial institution Current Noncurrent Total Current Noncurrent Total Local currency 12th issue debentures 45,450 113,049 158,499 45,450 158,425 203,875 14th issue debentures 25,388 — 25,388 51,873 24,205 76,078 17th issue debentures 102,252 101,982 204,234 91,850 183,335 275,185 18th issue debentures 48,479 92,677 141,156 45,918 135,105 181,023 21st issue debentures 174,849 — 174,849 175,000 174,769 349,769 22nd issue debentures 200,000 508,530 708,530 99,969 678,149 778,118 23rd issue debentures — 864,776 864,776 — 864,678 864,678 24th issue debentures — 461,350 461,350 — 414,994 414,994 25th issue debentures — — — 1,442,610 — 1,442,610 26th issue debentures — 1,168,317 1,168,317 — 1,047,767 1,047,767 27th issue debentures — 997,433 997,433 — 997,000 997,000 28th issue debentures — 1,197,395 1,197,395 — — — 29th issue debentures — 1,230,602 1,230,602 — — — Brazilian Federal Savings Bank 98,784 1,380,170 1,478,954 90,382 1,324,459 1,414,841 Brazilian Development Bank - BNDES PAC 13,394 6,665 20,059 13,185 20,247 33,432 Brazilian Development Bank - BNDES PAC II 9751 7,161 30,308 37,469 7,159 37,447 44,606 Brazilian Development Bank - BNDES PAC II 9752 4,851 20,619 25,470 4,851 25,470 30,321 Brazilian Development Bank - BNDES ONDA LIMPA 26,751 60,089 86,840 26,751 86,809 113,560 Brazilian Development Bank - BNDES TIETÊ III 117,593 617,251 734,844 86,823 542,519 629,342 Brazilian Development Bank - BNDES 2015 33,558 420,685 454,243 33,558 454,126 487,684 Brazilian Development Bank - BNDES 2014 6,524 22,874 29,398 5,143 23,017 28,160 Inter-American Development Bank - BID 2202 181,349 2,344,403 2,525,752 181,349 2,524,798 2,706,147 Inter-American Development Bank - BID INVEST 34,800 890,400 925,200 44,815 898,060 942,875 Leases (Concession Agreements, Program Contracts and Contract Assets) 36,640 360,671 397,311 28,847 399,896 428,743 Leases (Others) 69,306 56,663 125,969 36,576 9,300 45,876 Other 4,790 9,274 14,064 3,778 11,382 15,160 Interest and charges 239,581 — 239,581 158,918 — 158,918 Total in local currency 1,471,500 12,956,183 14,427,683 2,674,805 11,035,957 13,710,762 Borrowings and financing outstanding balance December 31, 2021 December 31, 2020 Financial institution Current Noncurrent Total Current Noncurrent Total Foreign currency Inter-American Development Bank - BID 1212 – US$41,112 thousand (US$51,390 thousand in December 2020) 57,357 172,071 229,428 53,412 213,649 267,061 Inter-American Development Bank - BID 4623 – US$30,329 thousand (US$ 10.220 thousand in December 2020) — 155,192 155,192 — 46,474 46,474 International Bank of Reconstruction and Development -BIRDs 7662 e 8906 – US$76,712 thousand (US$82,792 thousand in December 2020) 33,927 386,328 420,255 31,594 393,949 425,543 JICA 15 – ¥9,219,440 thousand (¥10,371,870 thousand in December 2020) 55,858 391,008 446,866 58,117 464,936 523,053 JICA 18 – ¥8,289,280 thousand (¥9,325,440 thousand in December 2020) 50,223 351,398 401,621 52,253 417,846 470,099 JICA 17 – ¥3,706,564 thousand (¥3,349,203 thousand in December 2020) 12,833 165,900 178,733 11,260 156,738 167,998 JICA 19 – ¥28,109,529 thousand (¥29,923,047 thousand in December 2020) 87,901 1,272,803 1,360,704 91,456 1,415,683 1,507,139 BID 1983AB – US$15,385 thousand (US$23,077 thousand in December 2020) 42,927 42,336 85,263 39,975 78,943 118,918 Interest and charges 18,091 — 18,091 21,577 — 21,577 Total in foreign currency 359,117 2,937,036 3,296,153 359,644 3,188,218 3,547,862 Total borrowings and financing 1,830,617 15,893,219 17,723,836 3,034,449 14,224,175 17,258,624 Exchange rate as of December 31, 2021: US$ 5.5805 0.04847 5.1967 0.05043 As of December 31, 2021, the Company did not have balances of borrowings and financing, raised during the year, to mature within 12 months. Schedule of borrowings terms Local currency Guarantees Maturity Annual interest rates Inflation adjustment 12th issue debentures Own funds 2025 TR + 9.5% 14th issue debentures Own funds 2022 TJLP +1.92% (Series 1 and 3) and 9.19% (Series 2) IPCA (Series 2) 17th issue debentures Own funds 2023 CDI +0.75% (Series 1) and 4.5% (Series 2) and 4.75% (Series 3) IPCA (Series 2 and 3) 18th issue debentures Own funds 2024 TJLP + 1.92 % (Series 1 and 3) and 8.25% (Series 2) IPCA (Series 2) 21st issue debentures Own funds 2022 CDI + 0.60% e CDI+ 0.90% 22nd issue debentures Own funds 2025 CDI +0.58% (Series 1) and CDI + 0.90% (Series 2) and 6.0% (Series 3) IPCA (Series 3) 23rd issue debentures Own funds 2027 CDI +0.49% (Series 1) and CDI + 0.63% (Series 2) 24th issue debentures Own funds 2029 3.20% (Series 1) and 3.37% (Series 2) IPCA (Series 1 and 2) 25th issue debentures Own funds 2021 CDI + 3.3% 26th issue debentures Own funds 2030 4.65% (series 1) and 4.95% (series 2) IPCA (series 1 and 2) 27th issue debentures Own funds 2027 CDI +1.60% (Series 1) and CDI + 1.80% (Series 2) and 2.25% (Series 3) 28th issue debentures Own funds 2028 CDI +1.20% (Series 1) and CDI + 1.44% (Series 2) and 1.60% (Series 3) 29th issue debentures Own funds 2036 CDI +1.29% (Series 1) and 5.3058% (Series 2) and 5.4478% (Series 3) IPCA (series 2 and 3) Brazilian Federal Savings Bank Own funds 2021/2042 5% to 9.5% TR Brazilian Development Bank - BNDES PAC Own funds 2023 TJLP+1.82% Brazilian Development Bank - BNDES PAC II 9751 Own funds 2027 TJLP+1.72% Brazilian Development Bank - BNDES PAC II 9752 Own funds 2027 TJLP+1.72% Brazilian Development Bank - BNDES ONDA LIMPA Own funds 2025 TJLP+1.92% Brazilian Development Bank - BNDES TIETÊ III Own funds 2028 TJLP+1.66% Brazilian Development Bank - BNDES 2015 Own funds 2035 TJLP+2.18% Brazilian Development Bank - BNDES 2014 Own funds 2026 TJLP+1.76% Inter-American Development Bank – BID 2202 Government 2035 CDI+0.86% Inter-American Development Bank – BID INVEST Own funds 2034 CDI+1.90% and CDI+2.70% Leases (Concession Agreements, Program Contracts and Contract Assets) 2035 7.73% to 10.12% IPC Leases (Others) 2023 4.25% to 12.34% Other Own funds 2025 3% (FEHIDRO) and TJLP + 1.5% (FINEP) Foreign currency Guarantees Maturity Annual interest rates Exchange rate changes Inter-American Development Bank - BID 1212 - US$41,112 thousand Government 2025 3.31% (*) US$ Inter-American Development Bank - BID 4623 - US$30,329 thousand Government 2044 1.12% (*) US$ International Bank for Reconstruction and Development – BIRDs 7662 and 8906 - US$76,712 thousand Government 2034 2.85% (*) US$ JICA 15 – ¥9,219,440 thousand Government 2029 1.8% and 2.5% Yen JICA 18 – ¥8,289,280 thousand Government 2029 1.8% and 2.5% Yen JICA 17– ¥3,706,564 thousand Government 2035 1.2% and 0.01% Yen JICA 19– ¥28,109,529 thousand Government 2037 1.7% and 0.01% Yen BID 1983AB – US$15,385 thousand - 2023 2.08% to 2.38% (*) US$ (*) Rates comprising LIBOR + contractually defined spread. (i) Payment schedule – book value as of December 31, 2021 Schedule of borrowings payment schedule 2022 2023 2024 2025 2026 2027 2028 to 2044 TOTAL LOCAL CURRENCY Debentures 596,418 694,806 1,062,558 1,194,424 1,074,178 1,153,648 1,556,497 7,332,529 Brazilian Federal Savings Bank 98,784 94,055 93,315 99,152 105,355 111,936 876,357 1,478,954 BNDES 209,832 203,103 196,438 176,274 166,466 154,029 282,181 1,388,323 BID 2202 181,349 181,349 181,349 181,349 181,349 181,349 1,437,658 2,525,752 BID INVEST 34,800 37,340 39,550 44,300 106,390 108,728 554,092 925,200 Leases (Concession Agreements, Program Contracts and Contract Assets) 36,640 39,132 40,228 44,322 30,846 30,481 175,662 397,311 Leases (Others) 69,306 40,094 9,640 5,656 1,273 — — 125,969 Other 4,790 4,719 2,393 2,162 — — — 14,064 Interest and charges 239,581 — — — — — — 239,581 TOTAL IN LOCAL CURRENCY 1,471,500 1,294,598 1,625,471 1,747,639 1,665,857 1,740,171 4,882,447 14,427,683 FOREIGN CURRENCY BID 57,357 57,357 57,357 61,811 8,908 8,908 132,922 384,620 BIRD 33,927 33,928 33,928 33,928 33,928 33,928 216,688 420,255 JICA 206,815 206,815 206,815 206,815 206,815 206,815 1,147,034 2,387,924 BID 1983AB 42,927 42,336 — — — — — 85,263 Interest and charges 18,091 — — — — — — 18,091 TOTAL IN FOREIGN CURRENCY 359,117 340,436 298,100 302,554 249,651 249,651 1,496,644 3,296,153 Overall Total 1,830,617 1,635,034 1,923,571 2,050,193 1,915,508 1,989,822 6,379,091 17,723,836 (ii) Changes Schedule of changes in borrowings December 31, 2020 Addition (lease) Funding Borrowing costs Monetary and exchange variation Inflation adjustment / exchange variation and incorporated interest – Capitalized Interest paid Amortization Accrued interest Provision for interest and fees – Capitalized Expenses with borrowing costs December 31, 2021 LOCAL CURRENCY Debentures 6,756,504 — 2,450,000 (25,717) 225,106 — (387,618) (1,963,282) 258,114 139,563 15,298 7,467,968 Brazilian Federal Savings Bank 1,418,832 — 156,488 — 685 — (113,030) (93,064) 79,966 33,236 — 1,483,113 BNDES 1,370,902 — 207,136 — — — (88,084) (186,179) 51,122 37,688 259 1,392,844 BID 2202 2,730,195 — — — — — (97,829) (181,349) 63,964 73,506 955 2,589,442 BID INVEST 944,513 — — — — — (33,276) (18,340) 63,380 — 665 956,942 Leases (Concession Agreements, Program Contracts and Contract Assets) 428,743 — — — — — (52,250) (31,432) 52,250 — — 397,311 Leases (Others) 45,876 140,187 — — — — (15,782) (76,013) 31,701 — — 125,969 Other 15,197 — 2,921 (32) — — (718) (3,986) 690 22 — 14,094 TOTAL IN LOCAL CURRENCY 13,710,762 140,187 2,816,545 (25,749) 225,791 — (788,587) (2,553,645) 601,187 284,015 17,177 14,427,683 FOREIGN CURRENCY BIDs 317,302 — 108,728 (7,620) 22,979 — (8,488) (53,197) 7,936 — 197 387,837 BIRD 426,860 — — (3,377) 30,814 — (2,481) (32,965) 1,789 — 241 420,881 Eurobonds 2,684,321 — 34,360 (76) (108,851) 10,198 (43,184) (216,190) 35,315 5,802 192 2,401,887 JICA 119,379 — — — 6,536 — (2,705) (40,607) 1,753 777 415 85,548 BID 1983AB 3,547,862 — 143,088 (11,073) (48,522) 10,198 (56,858) (342,959) 46,793 6,579 1,045 3,296,153 TOTAL IN FOREIGN CURRENCY 17,258,624 140,187 2,959,633 (36,822) 177,269 10,198 (845,445) (2,896,604) 647,980 290,594 18,222 17,723,836 December 31, 2019 Foreign/local currency translation Addition (lease) Funding Borrowing costs Monetary and exchange variation Inflation adjustment / exchange variation and incorporated interest – Capitalized Interest paid Amortization Accrued interest Provision for interest and fees – Capitalized Expenses with borrowing costs December 31, 2020 LOCAL CURRENCY Debentures 3,711,228 — — 3,507,640 (52,328) 86,939 — (161,494) (572,871) 201,150 26,073 10,167 6,756,504 Brazilian Federal Savings Bank 1,429,250 — — 74,485 — — — (111,601) (84,821) 73,067 38,452 — 1,418,832 BNDES 1,201,411 — — 213,514 — — — (47,164) (81,213) 47,668 36,427 259 1,370,902 BID 2202 — 2,807,371 — — — — — (37,613) (90,674) 22,668 27,886 557 2,730,195 BID INVEST — — — 950,000 (7,125) — — — — 1,638 — — 944,513 Leases (Concession Agreements, Program Contracts and Contract Assets) 459,671 — — — — — — (51,431) (30,928) 51,431 — — 428,743 Leases (Others) 74,453 — 28,549 — — — — (9,108) (56,571) 8,553 — — 45,876 Other 9,898 — — 7,250 — — — (671) (1,962) 651 31 — 15,197 TOTAL IN LOCAL CURRENCY 6,885,911 2,807,371 28,549 4,752,889 (59,453) 86,939 — (419,082) (919,040) 406,826 128,869 10,983 13,710,762 FOREIGN CURRENCY BIDs 2,316,190 (2,807,371) — 52,141 (6,635) 845,246 48,246 (45,010) (121,088) 10,490 24,695 398 317,302 BIRD 357,880 — — — (2,029) 102,029 1,217 (7,572) (31,216) 5,659 752 140 426,860 Eurobonds 1,413,956 — — — — 457,931 — (104,170) (1,868,676) 90,941 9,195 823 — JICA 2,106,908 — — 40,830 (117) 715,956 17,841 (43,758) (200,597) 40,172 6,897 189 2,684,321 BID 1983AB 163,864 — — — (152) 59,078 — (7,033) (103,482) 5,843 618 643 119,379 TOTAL IN FOREIGN CURRENCY 6,358,798 (2,807,371) — 92,971 (8,933) 2,180,240 67,304 (207,543) (2,325,059) 153,105 42,157 2,193 3,547,862 TOTAL 13,244,709 — 28,549 4,845,860 (68,386) 2,267,179 67,304 (626,625) (3,244,099) 559,931 171,026 13,176 17,258,624 December 31, 2018 Addition as per IFRS 16 Funding Borrowing costs Monetary variation and exchange rate changes Inflation adjustment / exchange rate changes - Capitalized Interest paid Amortization Accrued interest Provision for interest and fees - Capitalized Amortization of borrowing costs December 31, 2019 LOCAL CURRENCY Debentures 3,486,861 — 1,266,755 (11,814) 42,692 — (234,307) (1,055,623) 195,586 17,233 3,845 3,711,228 Brazilian Federal Savings Bank 1,345,684 — 162,767 — — — (109,128) (79,404) 74,421 34,910 — 1,429,250 BNDES 1,072,605 — 256,981 (628) 2,082 826 (83,419) (131,026) 60,644 23,112 234 1,201,411 Leases (Concession Agreements, Program Contracts and Contract Assets) 568,666 — — — 1,765 3,761 (47,663) (123,880) 49,160 7,862 — 459,671 Leases (Others) (*) — 113,233 — — — — (1,141) (42,646) 5,007 — — 74,453 Other 9,571 — 1,683 — 28 — (655) (1,383) 652 2 — 9,898 TOTAL IN LOCAL CURRENCY 6,483,387 113,233 1,688,186 (12,442) 46,567 4,587 (476,313) (1,433,962) 385,470 83,119 4,079 6,885,911 FOREIGN CURRENCY BID 2,399,985 — — — 40,594 49,387 (83,602) (171,892) 26,332 54,431 955 2,316,190 BIRD 356,420 — 2,540 (2,540) 12,575 1,657 (10,627) (12,273) 8,548 1,561 19 357,880 Deutsche Bank 292,872 — — — 13,255 — (18,562) (303,866) 12,929 1,240 2,132 — Eurobonds 1,358,412 — — — 54,565 — (102,883) — 94,095 8,943 824 1,413,956 JICA 2,036,128 — 117,861 (112) 104,027 3,675 (35,001) (155,064) 32,194 3,013 187 2,106,908 BID 1983AB 225,592 — — (105) 8,943 — (10,338) (71,141) 9,111 870 932 163,864 TOTAL IN FOREIGN CURRENCY 6,669,409 — 120,401 (2,757) 233,959 54,719 (261,013) (714,236) 183,209 70,058 5,049 6,358,798 Overall Total 13,152,796 113,233 1,808,587 (15,199) 280,526 59,306 (737,326) (2,148,198) 568,679 153,177 9,128 13,244,709 (*) The amount presented in Funding for Leasing (IFRS 16) includes R$ 64,955 referring to the initial adoption of the standard on January 1, 2019. (a) Main events in 2021 (i) Debentures In 2021, there were amortizations in the amounts of R$ 91.7 100.0 175.0 1,585.9 1,450.0 135.9 28th issue debentures In July 2021, the Company raised R$ 1.2 billion The 28th issue debentures was as follows: Schedule of funding Value Maturity Remuneration Series 1 R$ 127,800 07/2024 CDI + 1.20 p.a. Series 2 R$ 888,200 07/2026 CDI + 1.44 p.a. Series 3 R$ 184,000 07/2028 CDI + 1.60 p.a. 29th issue debentures On December 2021, the Company raised the amount of R$1.25 billion referring to the 29th issue of simple and unsecured type debentures, non-convertible into shares, in up three series, according to CVM Instruction 400. The funds raised of the first series will be used to refinance commitments maturing and to recompose the Company's cash. The funds raised of the second and the third series will be used for investment, related to the execution of the projects: (i) Expansion of the Water Supply and Sanitary Sewage Systems in the Metropolitan Region of São Paulo (RMSP) and (ii) Expansion of the Sanitary Sewage System in Baixada Santista. The 29th issue debentures was as follows: Value Maturity Remuneration Series 1 R$ 500,000 12/2026 CDI + 1.29% p.a. Series 2 R$ 600,000 12/2031 IPCA + 5.3058% p.a. Series 3 R$ 150,000 12/2036 IPCA + 5.4478% p.a. The total amount of the commission was R$ 21,250 • The covenants agreed for the 28 th th Calculated every quarter, when disclosing the quarterly information or annual financial statements: - Net debt/adjusted EBITDA lower than or equal to 3.50; - Adjusted EBITDA/paid financial expenses equal to or higher than 1.5; - Disposal of operating assets, termination of licenses, loss of concession or loss of the Issuer’s ability to execute and operate public sanitation services in areas of the São Paulo State which, individually or jointly during the term of the agreement, lead to a reduction of the Issuer’s net sales and/or service revenue of more than twenty- five percent ( 25 The failure to comply with the covenants for at least two consecutive quarters, or for two non-consecutive quarters within twelve months, will cause the early termination of the agreement (in which case the 30-day cure period does not apply). The contracts have a cross acceleration clause, i.e. the early maturity of any of the Company’s debts, in an individual or aggregate amount equal to or higher than R$ 166 th 175 th (b) Leases The Company has work service agreements which includes specific assets under lease terms. During the construction period, works are capitalized to intangible assets in progress and the lease amount is recorded at the same proportion. After startup, the lease payment period starts (240 monthly installments) The amounts payable for the right of use of assets are also recorded in this line (Note 15 (g)). (c) Financial commitments - Covenants The table below shows the more restrictive covenants ratios as of December 31, 2021. Schedule of restrictive covenants ratios Covenants Adjusted EBITDA / Adjusted Financial Expenses Equal to or higher than 2.80 EBITDA / Financial Expenses Paid Equal to or higher than 2.35 Adjusted Net Debt / Adjusted EBITDA Equal to or lower than 3.80 Net Debt / Adjusted EBITDA Equal to or lower than 3.50 Total Adjusted Debt / Adjusted EBITDA Lower than 3.65 Other Onerous Debt (1) Equal to or lower than 1.30 Adjusted Current Ratio Higher than 1.00 (1) The contractual definition of “Other Onerous Debts” corresponds to the sum of pension plan obligations and healthcare plan, installment payments of tax debts, and installments payments of debts with the electricity supplier. As of December 31, 2021 and 2020, the Company met the financial debt covenants as set forth by its borrowing and financing agreements. (d) Borrowings and financing – Credit Limits Schedule of borrowings and financing - Credit Limits Agent December 31, 2021 (in millions of reais (*)) Brazilian Federal Savings Bank 1,353 Brazilian Development Bank – BNDES 455 Japan International Cooperation Agency – JICA 48 Inter-American Development Bank – BID 1,505 International Bank for Reconstruction and Development - IBRD 1,392 Other 16 TOTAL 4,769 (*) Brazilian Central Bank’s exchange sell rate as of December 30, 2021 (US$ 1.00 = R$ 5.5805 0.04847 Financing resources contracted have specific purposes, which have been released for the execution of their respective investments, according to the progress of the works.

Taxes recoverable_payable

Taxes recoverable/payable	12 Months Ended
	Dec. 31, 2021
Taxes recoverable/payable	18 Taxes recoverable/payable (a) Current assets December 31, 2021 December 31, 2020 Recoverable taxes Income tax and social contribution 259,902 — Withholding income tax (IRRF) on financial investments 13,041 4,391 Other federal taxes 3,161 18,281 Total 276,104 22,672 As of December 31, 2021, the Company recorded income tax and social contribution recoverable due to the overpayment resulting from these taxes' estimates in the year. In 2020, the balance of these taxes resulted in a liability, which was recorded under "Taxes and Contributions Payable". (b) Current liabilities December 31, 2021 December 31, 2020 Taxes and contributions payable Income tax and social contribution — 69,041 Cofins and Pasep 111,963 93,601 INSS (social security contribution) 39,902 37,599 IRRF (withholding income tax) 49,468 21,287 Other 55,797 45,291 Total 257,130 266,819

Deferred taxes and contribution

Deferred taxes and contributions	12 Months Ended
	Dec. 31, 2021
Deferred taxes and contributions	19 Deferred taxes and contributions (a) Statement of financial position details Schedule of deferred taxes December 31, 2021 December 31, 2020 Deferred income tax assets Provisions 503,374 436,445 Pension obligations - G1 150,577 154,498 Donations of underlying asset on concession agreements 47,589 50,142 Credit losses 183,963 155,719 Other 127,092 134,932 Total deferred tax assets 1,012,595 931,736 Deferred income tax liabilities Temporary difference on concession of intangible asset (368,235) (388,675) Capitalization of borrowing costs (404,931) (390,211) Profit on supply to government entities (353,262) (356,513) Actuarial gain/loss – G1 Plan (109,271) (48,979) Construction margin (46,079) (48,843) Borrowing costs (14,556) (19,231) Total deferred tax liabilities (1,296,334) (1,252,452) Deferred tax assets (liabilities), net (283,739) (320,716) (b) Realization Schedule of realization December 31, 2021 December 31, 2020 Deferred income tax assets to be realized within 12 months 280,373 263,580 to be realized after one year 732,222 668,156 Total deferred tax asset 1,012,595 931,736 Deferred income tax liabilities to be realized within 12 months (31,777) (31,388) to be realized after one year (1,264,557) (1,221,064) Total deferred tax liabilities (1,296,334) (1,252,452) Deferred tax liability (283,739) (320,716) (c) Changes Schedule of changes Deferred income tax assets December 31, 2020 Net change December 31, 2021 Provisions 436,445 66,929 503,374 Pension obligations - G1 154,498 (3,921) 150,577 Donations of underlying asset on concession agreements 50,142 (2,553) 47,589 Credit losses 155,719 28,244 183,963 Other 134,932 (7,840) 127,092 Total 931,736 80,859 1,012,595 Deferred income tax liabilities Temporary difference on concession of intangible asset (388,675) 20,440 (368,235) Capitalization of borrowing costs (390,211) (14,720) (404,931) Profit on supply to governmental entities (356,513) 3,251 (353,262) Actuarial (gain)/loss – G1 (48,979) (60,292) (109,271) Construction margin (48,843) 2,764 (46,079) Borrowing costs (19,231) 4,675 (14,556) Total (1,252,452) (43,882) (1,296,334) Deferred tax liabilities, net (320,716) 36,977 (283,739) Deferred income tax assets December 31, 2019 Net change December 31, 2020 Provisions 366,673 69,772 436,445 Pension obligations - G1 157,998 (3,500) 154,498 Donations of underlying asset on concession agreements 51,818 (1,676) 50,142 Credit losses 145,622 10,097 155,719 Other 183,147 (48,215) 134,932 Total 905,258 26,478 931,736 Deferred income tax liabilities Temporary difference on concession of intangible asset (408,732) 20,057 (388,675) Capitalization of borrowing costs (409,236) 19,025 (390,211) Profit on supply to governmental entities (372,289) 15,776 (356,513) Actuarial (gain)/loss – G1 (54,222) 5,243 (48,979) Construction margin (83,399) 34,556 (48,843) Borrowing costs (11,376) (7,855) (19,231) Total (1,339,254) 86,802 (1,252,452) Deferred tax liabilities, net (433,996) 113,280 (320,716) Deferred income tax assets December 31, 2018 Net change December 31, 2019 Provisions 337,833 28,840 366,673 Pension obligations - G1 157,044 954 157,998 Donations of underlying asset on concession agreements 54,131 (2,313) 51,818 Credit losses 197,920 (52,298) 145,622 Other 186,887 (3,740) 183,147 Total 933,815 (28,557) 905,258 Deferred income tax liabilities Temporary difference on concession of intangible asset (433,842) 25,110 (408,732) Capitalization of borrowing costs (420,978) 11,742 (409,236) Profit on supply to governmental entities (206,978) (165,311) (372,289) Actuarial (gain)/loss – G1 (36,430) (17,792) (54,222) Construction margin (86,164) 2,765 (83,399) Borrowing costs (10,665) (711) (11,376) Total (1,195,057) (144,197) (1,339,254) Deferred tax assets (liabilities), net (261,242) (172,754) (433,996) December 31, 2021 December 31, 2020 December 31, 2019 Opening balance (320,716) (433,996) (261,242) Net change in the year: - corresponding entry to the income statement 97,269 108,037 (154,962) - corresponding entry to valuation adjustments to equity (Note 21 (b)) (60,292) 5,243 (17,792) Total net change 36,977 113,280 (172,754) Closing balance (283,739) (320,716) (433,996) (d) Reconciliation of the effective tax rate The amounts recorded as income tax and social contribution expenses in the financial statements are reconciled to the statutory rates, as shown below: December 31, 2021 December 31, 2020 December 31, 2019 Profit before income taxes 3,170,156 1,326,002 4,677,942 Statutory rate 34% 34% 34% Estimated expense at statutory rate (1,077,853) (450,841) (1,590,500) Tax benefit of interest on equity 200,073 126,604 312,339 Permanent differences Provision – Law 4,819/1958 – G0 (i) (22,640) (37,675) (44,426) Donations (16,723) (8,672) (19,888) Other differences 52,856 17,900 32,050 Income tax and social contribution (864,287) (352,684) (1,310,425) Current income tax and social contribution (961,556) (460,721) (1,155,463) Deferred income tax and social contribution 97,269 108,037 (154,962) Effective rate 27% 27% 28% (i) Permanent difference related to the provision for actuarial liability (Note 22 (ii) and (v)).

Provisions

Provisions	12 Months Ended
	Dec. 31, 2021
Provisions	20 Provisions (a) Lawsuits and proceedings that resulted in provisions (I) Statement of financial position details The Company is party to a number of legal claims and administrative proceedings arising from the normal course of business, including civil, tax, labor and environmental matters. Management recognizes provisions in the financial statements consistently with the recognition and measurement criteria established in Note 3.15. The ultimate timing and amounts of the payments depends on the outcome of the court cases. Schedule of lawsuits and proceedings that resulted in provisions December 31, 2021 December 31, 2020 Provisions Escrow deposits Provisions net of deposits Provisions Escrow deposits Provisions net of deposits Customer claims (i) 168,258 (10,780) 157,478 160,705 (10,553) 150,152 Supplier claims (ii) 477,854 (123) 477,731 410,734 (358) 410,376 Other civil claims (iii) 95,601 (2,523) 93,078 86,083 (2,505) 83,578 Tax claims (iv) 57,509 (2,693) 54,816 59,678 (2,410) 57,268 Labor claims (v) 349,962 (15,864) 334,098 316,880 (15,503) 301,377 Environmental claims (vi) 331,326 (34) 331,292 249,582 (31) 249,551 Total 1,480,510 (32,017) 1,448,493 1,283,662 (31,360) 1,252,302 Current 809,821 — 809,821 760,209 — 760,209 Noncurrent 670,689 (32,017) 638,672 523,453 (31,360) 492,093 (II) Changes Schedule of changes in provisions December 31, 2020 Additional provisions Interest and inflation adjustment Use of the accrual Amounts not used (reversal) December 31, 2021 Customer claims (i) 160,705 32,996 29,685 (30,972) (24,156) 168,258 Supplier claims (ii) 410,734 92,135 90,788 (71,238) (44,565) 477,854 Other civil claims (iii) 86,083 15,477 12,850 (10,056) (8,753) 95,601 Tax claims (iv) 59,678 8,630 8,054 (15,133) (3,720) 57,509 Labor claims (v) 316,880 100,245 36,373 (66,220) (37,316) 349,962 Environmental claims (vi) 249,582 40,477 50,957 (33) (9,657) 331,326 Subtotal 1,283,662 289,960 228,707 (193,652) (128,167) 1,480,510 Escrow deposits (31,360) (39,586) (11,852) 48,805 1,976 (32,017) Total 1,252,302 250,374 216,855 (144,847) (126,191) 1,448,493 December 31, 2019 Additional provisions Interest and inflation adjustment Use of the accrual Amounts not used (reversal) December 31, 2020 Customer claims (i) 253,665 16,465 19,638 (78,640) (50,423) 160,705 Supplier claims (ii) 153,654 149,566 201,259 (68,801) (24,944) 410,734 Other civil claims (iii) 93,910 15,944 11,109 (23,009) (11,871) 86,083 Tax claims (iv) 59,143 4,333 2,737 (1,875) (4,660) 59,678 Labor claims (v) 325,129 61,782 35,541 (61,039) (44,533) 316,880 Environmental claims (vi) 192,950 35,392 27,718 — (6,478) 249,582 Subtotal 1,078,451 283,482 298,002 (233,364) (142,909) 1,283,662 Escrow deposits (42,643) (12,907) (2,225) 18,675 7,740 (31,360) Total 1,035,808 270,575 295,777 (214,689) (135,169) 1,252,302 December 31, 2018 Additional provisions Interest and inflation adjustment Use of the accrual Amounts not used (reversal) December 31, 2019 Customer claims (i) 290,649 57,314 53,929 (99,379) (48,848) 253,665 Supplier claims (ii) 67,985 54,223 102,686 (42,948) (28,292) 153,654 Other civil claims (iii) 98,302 28,888 18,713 (9,766) (42,227) 93,910 Tax claims (iv) 63,335 11,821 2,918 (4,982) (13,949) 59,143 Labor claims (v) 302,935 167,995 61,483 (112,084) (95,200) 325,129 Environmental claims (vi) 170,419 42,198 24,358 (312) (43,713) 192,950 Subtotal 993,625 362,439 264,087 (269,471) (272,229) 1,078,451 Escrow deposits (100,763) (14,051) (11,844) 19,191 64,824 (42,643) Total 892,862 348,388 252,243 (250,280) (207,405) 1,035,808 (b) Lawsuits deemed as contingent liabilities The Company is party to lawsuits and administrative proceedings relating to environmental, tax, civil and labor claims, which are assessed as contingent liabilities in the financial statements, since it either does not expect outflows to be required or the amount of the obligation cannot be reliably measured. Contingent liabilities, net of escrow deposits, are represented as follows: December 31, 2021 December 31, 2020 Customer claims (i) 173,875 110,508 Supplier claims (ii) 1,521,935 1,350,308 Other civil claims (iii) 852,735 758,800 Tax claims (iv) 1,548,781 1,253,636 Labor claims (v) 1,095,841 1,005,648 Environmental claims (vi) 3,201,716 5,981,837 Total 8,394,883 10,460,737 (c) Explanation on the nature of main classes of lawsuits (i) Customer claims Refer to actions by commercial customers, who claim that their tariffs should correspond to other consumer categories, actions in which customers claim a reduction in the sewage tariff due to losses in the system, consequently requesting the refund of amounts charged by the Company and actions in which customers plead the reduction in tariff under the category as “Social Welfare Entity”. (ii) Supplier claims These lawsuits include lawsuits filed by some suppliers alleging underpayment of monetary restatements and the economic and financial imbalance of the agreements, and are in progress at different courts. (iii) Other civil claims These mainly refer to indemnities for property damage, pain and suffering, and loss of profits allegedly caused to third parties, such as vehicle accidents, claims, challenges on the methodology to collect tariffs, among others, filed at different court levels. (iv) Tax claims Tax claims refer mainly to issues related to tax collections and fines in general challenged due to disagreements regarding notification or differences in the interpretation of legislation by the Company's Management, that were accrued and others that were deemed as contingent liabilities. The municipality of São Paulo, through law, revoked the services tax exemption which until then the company withheld and thereafter issued tax deficiency notices related to the sewage service and ancillary activities, in the updated amount of R$ 857,688 (R$ 731,809 as of December 31, 2020), which currently are subject-matter of three Tax Foreclosures. SABESP filed a writ of mandamus against this revocation, which was rejected. Writs of prevention and actions for annulment were also filed, aiming the suspension of enforceability of credits and the annulment of tax deficiency notices, as it understands that notwithstanding the exemption revocation, the sewage activities and ancillary activities are not included in the list of activities subject to taxation by municipality. The appellate decision was favorable to the Company. The Municipality’s special and extraordinary appeal is still pending. The Company deemed the proceeding as contingent liability. (v) Labor claims The Company is a party to a number of labor lawsuits, involving issues such as overtime, shift schedule, health hazard premium and hazardous duty premium, prior notice, change of function, salary equalization, service outsourcing and other, which are at various court levels. (vi) Environmental claims These refer to several administrative proceedings and lawsuits filed by government entities, including Companhia Ambiental do Estado de São Paulo – CESTESB and the Public Prosecution Office of the State of São Paulo, which aim at certain obligations to do and not to do, with the provision of fines for non-compliance, and imposition of compensation for environmental damages allegedly caused by the Company. The main objects in which the Company is involved are: a) blame SABESP for discharging or releasing sewage without proper treatment; b) invest in the water and sewage treatment system of the municipality, under penalty of paying a fine; c) pay compensation for environmental damages; amongst others. The decrease in contingent liabilities was mainly due to reviews of lawsuit expectations, resulting from court decisions favorable to the Company. (d) Other concession-related legal proceedings The Company is a party to concessions-related legal proceedings, in which it challenges compensatory issues for the resumption of sanitation services by some municipalities or by the right to continue operating said services. The amount recorded as indemnities receivable in noncurrent assets, referring to municipalities of Cajobi, Macatuba, Álvares Florence, Embaúba, Araçoiaba da Serra and Itapira was R$ 27,539 as December 31, 2021 (R$ 27,539 as of December 31, 2020), with allowance for doubtful accounts in the full amount recorded. None of the above-mentioned municipalities are operated by the Company. When a municipality is awarded a final an unappealable favorable sentence, allowing it to repossess sanitation service assets and operations, the Brazilian legislation provides for the indemnity of the Company’s investments. (e) Environmental lawsuits with settlements During 2021, the Company did not enter into a legal agreement with any municipality. (f) Guarantee insurance for escrow deposit On May 25, 2021, the Company executed an agreement effective for one year for the issue of policies under several types of guarantee insurance. The limit that can be used for guarantee insurance for escrow deposit is R$ 600 . The guarantee insurance for escrow deposit is used in legal claims, where instead of immediately disbursing cash, the Company uses the guarantee provided by the insurance until the end of these proceedings, limited to up to five years . As of December 31, 2021, R$ 555 was available for use.

Labor and social obligations

Labor and social obligations	12 Months Ended
	Dec. 31, 2021
Labor and social obligations	21 Labor and social obligations Schedule of employees benefits December 31, 2021 December 31, 2020 Salaries and payroll charges 58,591 53,107 Provision for vacation 226,127 207,906 Healthcare plan (i) 45,915 45,768 Provision for profit sharing (ii) 88,376 91,209 Consent Decree (TAC) 5,723 8,978 Knowledge Retention Program (PRC) 1,884 3,975 Total 426,616 410,943 (i) Health plan – Medical Assistance Since August 1, 2019, the new health plans managed by Fundação CESP (VIVEST), which replaced the previous health plans managed by SABESPREV, have been in effect. Benefits became post-payment, with the premise of free choice remaining, maintained by contributions from the sponsor and employees. In 2021, the Company participated on average with 8.50 % of the gross payroll, totaling R$ 232,850 (in 2020 it was 7.79 %, totaling R$ 212,681 ). (ii) Profit sharing The profit sharing program was implemented in accordance with an agreement with the labor union. Payment corresponds to up to one-month salary for each employee, depending on performance of goals reached from January to December, and should be paid in April of the subsequent year.

Pension plan obligations

Pension plan obligations	12 Months Ended
	Dec. 31, 2021
Pension Plan Obligations
Pension plan obligations	22 Pension plan obligations The Company has Post-Employment Benefit Plans in the following modalities: Defined Benefit (BD) – G1 (i) and G0 (ii); Defined Contribution (CD) – Sabesprev Mais (iii) and VIVEST (iv). The reconciliation of costs and expenses with such plans is shown in item (v). Statements of defined benefit plans Summary of pension obligations – Liabilities Schedule of pension plan benefits December 31, 2021 December 31, 2020 G1 Plan G0 Plan Total G1 Plan G0 Plan Total Present value of the defined benefit obligations (2,764,027) (2,192,062) (4,956,089) (3,112,980) (2,549,541) (5,662,521) Fair value of the plan’s assets 2,634,427 — 2,634,427 2,793,927 — 2,793,927 Total pension plan liabilities (deficit) (129,600) (2,192,062) (2,321,662) (319,053) (2,549,541) (2,868,594) Changes in Liabilities Schedule of reconciliation of defined benefit obligations December 31, 2021 December 31, 2020 G1 Plan G0 Plan Total G1 Plan G0 Plan Total Plan’s liabilities Defined benefit obligation, beginning of the year (3,112,980) (2,549,541) (5,662,521) (3,067,094) (3,046,255) (6,113,349) Current service cost (32,777) — (32,777) (40,404) — (40,404) Interest costs (205,707) (158,244) (363,951) (208,485) (206,262) (414,747) Actuarial (gains)/losses recorded as other comprehensive income 414,823 330,337 745,160 64,637 521,331 585,968 Benefits paid 172,614 185,386 358,000 138,366 181,645 320,011 Defined benefit obligation, end of the year (2,764,027) (2,192,062) (4,956,089) (3,112,980) (2,549,541) (5,662,521) Plan’s assets Fair value of the plan’s assets, beginning of the year 2,793,927 — 2,793,927 2,752,417 — 2,752,417 Expected return of the plan’s assets 184,687 — 184,687 187,317 — 187,317 Company’s contributions 35,368 — 35,368 36,010 — 36,010 Participant’s contributions 30,551 — 30,551 36,608 — 36,608 Benefits paid (172,614) — (172,614) (138,366) — (138,366) Actuarial gains/(losses) recorded as other comprehensive income (237,492) — (237,492) (80,059) — (80,059) Fair value of the plan’s assets, end of the year 2,634,427 — 2,634,427 2,793,927 — 2,793,927 Total pension plan liabilities (deficit) (129,600) (2,192,062) (2,321,662) (319,053) (2,549,541) (2,868,594) Changes in equity - Other comprehensive income Pursuant to IAS19, the Company recognized gains/(losses), from changes in actuarial assumptions under equity, such as equity valuation adjustments, as shown below: Schedule of (gains)/losses, due to changes in assumptions December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan G0 Plan Total G1 Plan G0 Plan Total G1 Plan G0 Plan Total Actuarial gains/(losses) on obligations 414,823 330,337 745,160 64,637 521,331 585,968 (392,876) (397,597) (790,473) Actuarial gains/(losses) recorded as other comprehensive income (237,492) — (237,492) (80,059) — (80,059) 445,206 — 445,206 Total gains/(losses) 177,331 330,337 507,668 (15,422) 521,331 505,909 52,330 (397,597) (345,267) Deferred income tax and social contribution (60,292) — (60,292) 5,243 — 5,243 (17,792) — (17,792) Equity valuation adjustments 117,039 330,337 447,376 (10,179) 521,331 511,152 34,538 (397,597) (363,059) The amounts recognized in the year are as follows: Schedule of amounts recognized in income statement December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan G0 Plan Total G1 Plan G0 Plan Total G1 Plan G0 Plan Total Cost of service, net 2,227 — 2,227 4,608 — 4,608 8,609 227,367 235,976 Interest cost rates 205,707 158,244 363,951 208,485 206,262 414,747 224,429 — 224,429 Expected return on the plan’s assets (184,687) — (184,687) (187,317) — (187,317) (192,965) — (192,965) Amount received from State of São Paulo (undisputed) — (91,657) (91,657) — (95,452) (95,452) — (97,300) (97,300) Total expenses 23,247 66,587 89,834 25,776 110,810 136,586 40,073 130,067 170,140 Obligations’ maturity: December 31, 2021 G1 Plan G0 Plan Payment of benefits expected in 2022 198,074 179,875 Payment of benefits expected in 2023 188,437 173,944 Payment of benefits expected in 2024 178,787 167,140 Payment of benefits expected in 2025 169,738 159,604 Payment of benefits expected in 2026 or after 2,028,991 1,511,499 Total 2,764,027 2,192,062 Duration 11.63 years 9.24 years Actuarial assumptions: December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan G0 Plan G1 Plan G0 Plan G1 Plan G0 Plan Discount rate – actual rate (NTN-B) 5.53% p.a. 5.26% p.a. 3.44% p.a. 3.07% p.a. 3.37% p.a. 3.36% p.a. Inflation rate 3.00% p.a. 3.00% p.a. 3.25% p.a. 3.25% p.a. 3.5% p.a. 3.5% p.a. Nominal rate of salary growth 5.06% p.a. 5.06% p.a 5.32% p.a. 5.32% p.a 5.57% p.a. 5.57% p.a Mortality table AT-2000 AT-2000 AT-2000 AT-2000 AT-2000 AT-2000 Sensitivity analysis Sensitivity analysis of the defined benefit pension plan as of December 31, 2021 regarding the changes in the main assumptions are: Impact on the present value of the defined benefit obligations Assumptions Change in the assumption G1 G0 Discount rate Increase of 1.0% Decrease of R$ 244,999 Decrease of R$ 158,221 Decrease of 1.0% Increase of R$ 289,735 Increase of R$ 180,948 Life expectation Increase of 1 year Increase of R$ 61,361 Increase of R$ 101,021 Decrease of 1 year Decrease of R$ 56,181 Decrease of R$ 90,081 Wage growth rate Increase of 1.0% Increase of R$ 19,402 Increase of R$ 227,529 Decrease of 1.0% Decrease of R$ 16,464 Decrease of R$ 202,363 (i) G1 Plan Managed by Sabesprev, the defined benefit plan (“G1 Plan”), closed to new adhesions since July 2010, receives similar contributions established in a plan of subsidy of actuarial study of Sabesprev, as follows: 0.99% of the portion of the salary of participation up to 20 salaries; and 8.39% of the surplus, if any, of the portion of the salary of participation over 20 salaries. The active participants as of December 31, 2021 totaled 2,930 ( 3,512 as of December 31, 2020), while inactive participants were 8,109 ( 7,580 as of December 31, 2020). The contributions of the Company and participants of the G1 Plan in 2021 were R$ 35,368 (R$ 36,009 in 2020) and R$ 30,551 (R$ 36,608 in 2020), respectively. Of this amount, the Company and the participants’ payments corresponding to the actuarial deficit of the G1 pension plan totaled R$ 28,829 and R$ 23,609 , respectively, in 2021 (R$ 26,326 and R$ 26,895 , respectively, in 2020). Estimated expenses for the comig year 2022 Cost of services, net 1,020 Interest costs 231,745 Net profitability on financial assets (221,079) Expenditures to be recognized by the employer 11,686 Plan’s assets The plan’s investment policies and strategies are aim at getting consistent returns and reduce the risks associated to the utilization of financial assets available on the Capital Markets through diversification, considering factors, such as the liquidity needs and the long-term nature of the plan liability, types and availability of financial instruments in the local and international markets, general economic conditions and forecasts as well as requirements under the law. The plan's asset allocation management strategies are determined with the support of reports and analysis prepared by Sabesprev and independent financial advisors: Schedule Of Plan’s Assets December 31, 2021 % December 31, 2020 % Total fixed income 1,613,153 61.2 1,811,164 64.8 Total equities 261,665 9.9 311,958 11.2 Total structured investments 599,970 22.8 575,943 20.6 Other 159,639 6.1 94,862 3.4 Fair value of the plan’s assets 2,634,427 100 2,793,927 100 Restrictions with respect to asset portfolio investments, in the case of federal government securities: i) instruments securitized by the National Treasury will not be permitted; ii) derivative instruments must be used for hedge. Restrictions with respect to asset portfolio investments, in the case of variable-income securities for internal management, are as follows: i) day-trade operations will not be permitted; ii) sale of uncovered share is prohibited; iii) swap operations without guarantee are prohibited iv) leverage will not be permitted, i.e., operations with derivatives representing leverage of asset or selling short, such operations cannot result in losses higher than invested amounts. As of December 31, 2020, Sabesprev did not have financial assets issued by the Company in its own portfolio; however, said assets could have been part of the investment fund portfolio invested by the Foundation. The real estate held in the portfolio is not used by the Company. (ii) G0 Plan Pursuant to State Law 4,819/1958, employees who started providing services prior to May 1974 and retired as an employee of the Company acquired a legal right to receive supplemental pension payments, which rights are referred as "G0 Plan ". The Company pays these supplemental benefits on behalf of the State of São Paulo and makes claims for reimbursements from the State Government, which are recorded as accounts receivable from related parties, limited to the amounts considered virtually certain that will be reimbursed by the State of São Paulo. The number of active participants of Plan - Go as of December 31, 2021 was 8 ( 10 as of December 31, 2020). The number of beneficiaries, retirees and survivors as of December 31, 2021 was 1,794 ( 1,862 as of December 31, 2020). Estimated expenses for 2022 2022 Interest cost rate 176,953 Expense to be recognized 176,953 (iii) Sabesprev Mais Plan As of December 31, 2021, this Defined Contribution Plan administered by Sabesprev had 9,463 active and assisted participants ( 9,587 as of December 31, 2020). With respect to the Sabesprev Mais plan, the contributions from the sponsor represent 100% over the total basic contribution from the participants. (iv) VIVEST Since December 31, 2019, the Sabesprev Mais Plan has not been accepting any new adhesions and, since January 1, 2020, new employees have the option to enroll in Fundação CESP’s Defined Contribution Plan (VIVEST), as well as those who did not enroll in the Sabesprev Mais Plan. As of December 31, 2021, it had 46 participants ( 24 participants as of December 31, 2020). (v) Reconciliation of expenses with pension obligations December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan 23,247 25,776 40,073 G0 Plan 66,587 110,810 130,067 Sabesprev Mais Plan 22,406 21,700 22,461 VIVEST Plan 160 58 — Subtotal 112,400 158,344 192,601 Expenses capitalized in assets (4,118) (4,904) (6,022) Other 5,527 5,841 8,040 Pension plan obligations (Note 29) 113,809 159,281 194,619

Services payable

Services payable	12 Months Ended
	Dec. 31, 2021
Services payable	23 Services payable The services account records the balances payable, mainly from services received from third parties, such as supply of electric power, reading of hydrometers and delivery of water and sewage bills, cleaning, surveillance and security services, collection, legal counsel services, audit, marketing and advertising and consulting services, among others. This account also includes the amounts payable to the Municipal Fund of Environmental Sanitation and Infrastructure based on a percentage of the revenues from São Paulo municipal government (Note 15 (c) (v) (6)). The balances as of December 31, 2021 and 2020 were R$ 469,027 and R$ 453,750 , respectively.

Equity

Equity	12 Months Ended
	Dec. 31, 2021
Equity	24 Equity (a) Share capital As of December 31, 2021, and 2020, the authorized, subscribed and paid-in capital, in the amount of R$ 15,000.000 , was composed of 683,509,869 registered, book-entry common shares with no par value, as follows: December 31, 2021 December 31, 2020 Number of shares % Number of shares % State Department of Finance 343,506,664 50.3 343,507,729 50.26 Other shareholders In Brazil (1) 234,965,971 34.4 254,868,646 37.29 Abroad (2) (3) 105,037,234 15.3 85,133,494 12.45 683,509,869 100.0 683,509,869 100.00 (1) As of December 31, 2021, the common shares traded in Brazil were held by 40,428 shareholders. It includes six shares held by Companhia Paulista de Parcerias (CPP), which is controlled by the São Paulo State Government. (2) Shares traded as American Depositary Receipts (ADR) on the New York Stock Exchange, through The Bank New York Mellon, the depositary bank for the Company's ADRs. (3) Each ADR corresponds to 1 share. (b) Distribution of earnings Shareholders are entitled to a minimum mandatory dividend of 25% of the adjusted net income under Brazilian GAAP, calculated according to the Brazilian corporate law. The dividends do not bear interest and the amounts not claimed within three years from the date of the Shareholders' Meeting that approved them mature in favor of the Company. 2021 2020 2019 Profit for the year 2,305,869 973,318 3,367,517 (-) Legal reserve - 5% 115,293 48,666 168,376 2,190,576 924,652 3,199,141 Minimum mandatory dividend – 25% 547,645 231,163 799,785 Dividend per share and per ADS 0.80122 0.33820 1.17012 On April 29, 2021, the Shareholders’ General Meeting approved the distribution of additional dividends in the amount of R$ 40,806 related to 2020. Thus, the amount of R$ 26,376 , related to the portion exceeding the minimum mandatory dividends of 25%, established in the bylaws, recorded in the 2020 equity under “Additional proposed dividends” was transferred to current liabilities. These amounts started being paid in June 2021. The Company proposed dividends as interest on capital ad referendum 547,645 (R$ 231,163 in 2020) and additional proposed dividends in the amount of R$ 96,700 (R$ 40,806 in 2020), totaling R$ 644,345 (R$ 271,969 in 2020), corresponding to R$ 0.9427 per common share (R$ 0.3979 in 2020), to be resolved on the Shareholders’ Meeting to be held on April 28, 2022. The amount exceeding the minimum mandatory dividend due in the year of R$ 96,700 (R$ 40,806 in 2020) was reclassified into equity to the “Additional proposed dividends” account, this amount includes the withholding income tax of R$ 41,069 (R$ 14,430 in 2020). The Company charged interest on capital to minimum dividends by its net withholding income tax. The amount of R$ 41,069 (R$ 14,430 in 2020) referring to withholding income tax was recognized in current liabilities, in order to comply with tax liabilities related to the credit of interest on capital. The balance payable of interest on capital as of December 31, 2021 of R$ 548,006 (R$ 231,611 in 2020) refers to the amount of R$ 547,645 (R$ 231,163 in 2020) declared in 2021, net of withholding income tax and R$ 361 declared in prior years (R$ 448 in 2020). (c) Legal reserve Earnings reserve - legal reserve: created by allocating 5% of the net income for the year up to the limit of 20% of the share capital. The Company may not create the legal reserve in the year in which the balance of this reserve, plus the amount of the capital reserves, exceeds 30% of the share capital. The purpose of the legal reserve is to ensure the integrity of the share capital. It can only be used to offset losses or increase capital, but not to pay dividends . (d) Investments reserve Earnings reserve - investments reserve is specifically formed by the portion corresponding to own funds assigned to the expansion of the water supply and sewage treatment systems, based on capital budget approved by the Management. As of December 31, 2021 and 2020, the balance of investment reserve totaled R$ 8,297,489 and R$ 6,751,258 , respectively. Pursuant to paragraph four of article 28 of the by-laws, the Board of Directors may propose to the Shareholders’ Meeting that the remaining balance of profit for the year, after deducting the legal reserve and minimum mandatory dividends, be allocated to an investment reserve that will comply with the following criteria: I- its balance, jointly with the balance of the other earnings reserves, except for reserves for contingencies and realizable profits, may not exceed the capital stock; II- the reserve is intended to guarantee the investment plan and its balance may be used: a) to absorb losses, whenever necessary; b) to distribute dividends, at any moment; c) in share redemption, reimbursement or purchase transactions authorized by law; d) in incorporation to the capital stock. (e) Allocation of the profit for the year 2021 2020 2019 Profit (+) Profit for the year 2,305,869 973,318 3,367,517 (-) Legal reserve – 5% 115,293 48,666 168,376 (-) Minimum mandatory dividends 547,645 231,163 799,785 (-) Additional proposed dividends 96,700 40,806 141,203 Investment reserve recorded 1,546,231 652,863 2,258,153 Management will send for approval at the Shareholders’ Meeting, a proposal to reallocate retained earnings the amount of R$ 1,546,231 to the Investment Reserve account, in order to meet the investment needs foreseen in the Capital Budget. (f) Retained earnings Retained earnings (accumulated losses): the statutory balance of this account is zero as all retained earnings must be distributed or allocated to an earnings reserve. (g) Other comprehensive loss Gains and losses arising from changes in the actuarial assumptions are accounted for as equity valuation adjustments, net of the effects of income tax and social contribution effects. See Note 22 (b), the breakdown of amounts recorded in 2021 and 2020. G1 plan G0 plan Total Balance as of December 31, 2020 95,075 (496,077) (401,002) Actuarial gains/(losses) for the year (Note 22) 117,039 330,337 447,376 Balance as of December 31, 2021 212,114 (165,740) 46,374

Earnings per share

Earnings per share	12 Months Ended
	Dec. 31, 2021
Earnings per share	25 Earnings per share Basic and diluted Basic earnings per share is calculated by dividing the equity attributable to the Company’s owners by the weighted average number of outstanding common shares during the year. The Company does not have potentially dilutive common shares outstanding or debts convertible into common shares. Accordingly, basic and diluted earnings per share are equal. Schedule of earnings per share, basic and diluted 2021 2020 2019 Earnings attributable to Company’s owners 2,305,869 973,318 3,367,517 Weighted average number of common shares issued 683,509,869 683,509,869 683,509,869 Basic and diluted earnings per share (reais per share) 3.37 1.42 4.93

Operating segment information

Operating segment information	12 Months Ended
	Dec. 31, 2021
Operating segment information	26 Operating segment information Management, comprised of the Board of Directors and Board of Executive Officers, has determined the operating segment used to make strategic decisions, as sanitation services. Result Schedule of operating segment information 2021 Sanitation (i) Reconciliation to the financial statements (ii) Balance as per financial statements Gross operating revenue 16,304,206 4,376,739 20,680,945 Gross sales deductions (1,189,884) — (1,189,884) Net operating revenue 15,114,322 4,376,739 19,491,061 Costs, selling, general and administrative expenses (11,115,383) (4,278,337) (15,393,720) Income from operations before other operating expenses, net and equity accounting 3,998,939 98,402 4,097,341 Other operating income / (expenses), net (21,841) Equity accounting 22,079 Financial result, net (927,423) Income from operations before taxes 3,170,156 Depreciation and amortization (2,253,322) — (2,253,322) (i) See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information; (ii) Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (b). Result 2020 Sanitation (i) Reconciliation to the financial statements (ii) Balance as per financial statements Gross operating revenue 15,157,780 3,716,616 18,874,396 Gross sales deductions (1,076,855) — (1,076,855) Net operating revenue 14,080,925 3,716,616 17,797,541 Costs, selling, general and administrative expenses (9,796,821) (3,630,139) (13,426,960) Income from operations before other operating expenses, net and equity accounting 4,284,104 86,477 4,370,581 Other operating income / (expenses), net 107,656 Equity accounting 14,136 Financial result, net (3,166,371) Income from operations before taxes 1,326,002 Depreciation and amortization (2,037,112) — (2,037,112) (i) See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information; (ii) Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (e). Result 2019 Sanitation (i) Reconciliation to the financial statements (ii) Balance as per financial statements Gross operating revenue 16,134,032 2,946,566 19,080,598 Gross sales deductions (1,096,944) — (1,096,944) Net operating revenue 15,037,088 2,946,566 17,983,654 Costs, selling, general and administrative expenses (9,375,590) (2,881,394) (12,256,984) Income from operations before other operating expenses, net and equity accounting 5,661,498 65,172 5,726,670 Other operating income / (expenses), net (18,748) Equity accounting 3,701 Financial result, net (1,033,681) Income from operations before taxes 4,677,942 Depreciation and amortization (1,780,094) (1,780,094) (i) See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information; (ii) Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (b).

Insurance

Insurance	12 Months Ended
	Dec. 31, 2021
Insurance	27 Insurance The Company has insurance that covers, among others, fire and other damage to its assets and office buildings, and liability insurance against third parties. It also has civil liability insurance for the members of the Board of Directors and Board of Executive Officers (“D&O insurance”) and guarantee insurance for escrow deposit (as described in Note 20 (f)) and traditional guarantee insurance. . The risk assumptions adopted, given their nature, are not within the scope of a financial statement audit, and consequently have not been examined by our independent auditors . As of December 31, 2021, the Company’s insurance was as follows: Coverage Specified risks – fire 2,185,827 Engineering risk 2,254,238 Guarantee insurance for escrow deposit and traditional guarantee 600,000 * Civil liability– D&O (Directors and Officers) 100,000 Civil liability – works 172,140 Civil liability – operations 10,000 Other 26,900 Total 5,349,105 (*) SABESP has an agreement that allows issuing policies that total such insured amount. Of the total, R$ 98,530 thousand in policies with guarantee insurance were issued.

Operating revenue

Operating revenue	12 Months Ended
	Dec. 31, 2021
Operating revenue	28 Operating revenue (a) Revenue from sanitation services: 2021 2020 2019 Metropolitan Region of São Paulo 11,529,229 10,722,384 11,849,776 Regional Systems 4,774,977 4,435,396 4,284,256 Total 16,304,206 15,157,780 16,134,032 (b) Reconciliation from gross operating income to net operating income: 2021 2020 2019 Revenue from sanitation services (i) 16,304,206 15,157,780 16,134,032 Construction revenue 4,376,739 3,716,616 2,946,566 Sales tax (1,121,905) (1,009,358) (1,035,051) Regulatory, Control and Oversight Fee (TRCF) (67,979) (67,497) (61,893) Net revenue 19,491,061 17,797,541 17,983,654 (i) Includes the amount of R$ 80,329 corresponding to the TRCF charged from customers from the municipalities regulated by ARSESP (R$ 72,962 in 2020).

Operating costs and expenses

Operating costs and expenses	12 Months Ended
	Dec. 31, 2021
Operating costs and expenses	29 Operating costs and expenses Schedule of operating costs and expenses 2021 2020 2019 Operating costs Salaries, payroll charges and benefits (2,026,202) (1,958,395) (1,938,265) Pension plan obligations (36,771) (37,281) (49,564) Construction costs (Note 26) (4,278,337) (3,630,139) (2,881,394) General supplies (314,111) (244,054) (259,401) Treatment supplies (364,542) (338,756) (310,380) Outsourced services (1,517,196) (1,251,839) (1,250,890) Electricity (1,462,776) (1,214,831) (1,140,160) General expenses (717,352) (622,113) (647,804) Depreciation and amortization (2,082,755) (1,882,259) (1,659,779) (12,800,042) (11,179,667) (10,137,637) Selling expenses Salaries, payroll charges and benefits (265,435) (271,565) (270,549) Pension plan obligations (4,868) (5,059) (6,848) General supplies (7,976) (5,471) (10,332) Outsourced services (343,763) (290,512) (360,190) Electricity (1,340) (1,200) (1,333) General expenses (136,107) (118,278) (122,503) Depreciation and amortization (66,390) (59,201) (31,649) (825,879) (751,286) (803,404) Bad debt expense, net of recoveries (Note 10 (c)) (643,730) (444,826) (128,099) Administrative expenses Salaries, payroll charges and benefits (250,557) (257,829) (278,507) Pension plan obligations (72,170) (116,941) (138,207) General supplies (11,209) (14,237) (3,216) Outsourced services (250,801) (230,054) (197,357) Electricity (1,715) (1,359) (1,436) General expenses (357,564) (257,693) (407,250) Depreciation and amortization (104,177) (95,652) (88,666) Tax expenses (75,876) (77,416) (73,205) (1,124,069) (1,051,181) (1,187,844) Operating costs and expenses Salaries, payroll charges and benefits (2,542,194) (2,487,789) (2,487,321) Pension obligations (113,809) (159,281) (194,619) Construction costs (Note 26) (4,278,337) (3,630,139) (2,881,394) General supplies (333,296) (263,762) (272,949) Treatment supplies (364,542) (338,756) (310,380) Outsourced services (2,111,760) (1,772,405) (1,808,437) Electricity (1,465,831) (1,217,390) (1,142,929) General expenses (1,211,023) (998,084) (1,177,557) Depreciation and amortization (2,253,322) (2,037,112) (1,780,094) Tax expenses (75,876) (77,416) (73,205) Bad debt expense, net of recoveries (Note 10 (c)) (643,730) (444,826) (128,099) (15,393,720) (13,426,960) (12,256,984)

Financial Income (Expenses)

Financial Income (Expenses)	12 Months Ended
	Dec. 31, 2021
Financial Income (Expenses)	30 Financial Income (Expenses) Schedule of financial income (expenses) 2021 2020 2019 Financial expenses Interest and charges on borrowings and financing – local currency (517,235) (348,050) (331,367) Interest and charges on borrowings and financing – foreign currency (46,793) (136,257) (165,421) Other financial expenses (315,013) (328,413) (344,508) Income tax over international remittance — (15,134) (17,650) Inflation adjustment on borrowings and financing (225,791) (86,938) (44,802) Other inflation adjustments (172,632) (142,313) (107,584) Interest and inflation adjustments on provisions (i) (170,831) (267,654) (162,093) Total financial expenses (1,448,295) (1,324,759) (1,173,425) Financial income Inflation adjustment gains 198,907 120,957 91,180 Income on financial investments 150,632 75,522 151,622 Interest income 145,866 162,576 150,054 Cofins and Pasep (23,038) (22,328) (20,028) Other 41 4 14 Total financial income 472,408 336,731 372,842 Financial income (expenses), net before exchange rate changes (975,887) (988,028) (800,583) Exchange gains (losses) Exchange rate changes on borrowings and financing (ii) 48,522 (2,180,241) (233,960) Exchange rate changes on assets (36) 1,894 863 Other exchange rate changes (22) 4 (1) Exchange rate changes, net 48,464 (2,178,343) (233,098) Financial income (expenses), net (927,423) (3,166,371) (1,033,681)

Other operating income (expense

Other operating income (expenses), net	12 Months Ended
	Dec. 31, 2021
Other operating income (expenses), net	31 Other operating income (expenses), net Schedule of other operating income (expenses), net 2021 2020 2019 Other operating income, net 71,877 70,288 75,667 Other operating expenses (93,718) 37,368 (94,415) Other operating income (expenses), net (21,841) 107,656 (18,748) Other operating income includes the sale of property, plant and equipment, sale of contracts awarded in public bids, right to sell electricity, indemnities and reimbursement of expenses, fines and guarantees, property leases, reuse water, PURA projects and services, net of Cofins and Pasep. Other operating expenses consist mainly of derecognition of concessions assets due to obsolescence, discontinued construction works, unproductive wells, projects considered economically unfeasible, losses on property, plant and equipment, estimated losses and operational assets indemnification.

Commitments

Commitments	12 Months Ended
	Dec. 31, 2021
Commitments	32 Commitments The Company has agreements to manage and maintain its activities, as well as agreements to build new projects aiming at achieving the objectives proposed in its target plan. Below, the main unrecorded committed amounts as of December 31, 2020: 1 year 1-3 years 3-5 years More than 5 years Total Contractual obligations – Expenses 1,147,112 745,388 187,150 790,650 2,870,300 Contractual obligations – Investments 2,258,647 1,741,424 1,425,790 331,184 5,757,045 Total 3,405,759 2,486,812 1,612,940 1,121,834 8,627,345

Supplemental cash flow informat

Supplemental cash flow information	12 Months Ended
	Dec. 31, 2021
Supplemental Cash Flow Information
Supplemental cash flow information	33 Supplemental cash flow information Schedule of supplemental cash flow information 2021 2020 2019 Total additions to contract assets (Note 14) 4,759,789 3,948,158 3,532,283 Total additions to intangible assets (Note 15 (b)) 172,961 411,285 1,788,907 Items not affecting cash (see breakdown below) (1,236,081) (1,095,786) (2,125,943) Total additions to intangible assets as per statement of cash flows 3,696,669 3,299,657 3,195,247 Investments and financing operations affecting intangible assets but not cash: Interest capitalized in the year (Note 14 (a)) 300,792 238,330 233,251 Contractors payable 218,523 142,514 252,675 Program contract commitments — 4,422 35,817 Public Private Partnership - São Lourenço PPP (Note 15 (g)) — — 10,591 Performance agreements 478,177 314,720 78,296 Right of use 140,187 28,549 113,233 Construction margin (Note 26) 98,402 85,976 65,172 Agreement with the Municipality of Mauá — 280,774 — Agreement with the municipality of Santo André — — 1,336,908 Total 1,236,081 1,095,786 2,125,943

Events after the reporting peri

Events after the reporting period	12 Months Ended
	Dec. 31, 2021
Events after the reporting period	34 Events after the reporting period 30th Issue Debentures As of March 18, 2022, the Company raised R$ 1.0 billion from the 30th issue of simple, unsecured debentures, not convertible into shares, in two series, under CVM Instruction 476. The first and second series will mature in March 2027 and March 2029, respectively. The first series, totaling R$ 500.0 million, yields CDI + 1.30% p.a., with semi-annual interest payments. The second series, totaling R$ 500.0 million, yields CDI + 1.58% p.a., also with semi-annual interest payments. The proceeds from the Issue will be used to refinance financial commitments maturing in 2022 and to recompose and reinforce the Company’s cash position. ARSESP Resolution 1,278 - 2022 Tariff Adjustment As of March 17, 2022, ARSESP published Resolution 1,278, which addresses the 2022 tariff adjustment, in which the Company highlights the following points: Article 1. Approve the total adjustment of twelve point eight zero one nine percent (12.8019%) on the tariffs charged by Sabesp, according to the exhibits to this resolution, which consists of: I - Inflation from February 2021 to February 2022, measured by the IPCA, of 10.5437%. II - Efficiency factor (X Factor) to be discounted, of 0.2142%. III - Compensatory adjustment of 2.3932%, according to the calculation provided in NT.F.0010-2022. IV – GQI 2020 to be discounted, of 0.1490%, according to the calculation provided in NT.F.0010-2022. Article 6. Sabesp’s current tariff structure remains unchanged. Paragraph 1. The definitions that depend on the implementation of the new tariff structure are postponed until they become effective. Resolution 1,278 which defines the new tariff tables was published in the Official Gazette of the São Paulo State on March 17, 2022, and will become effective as of May 10, 2022.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Cash and cash equivalents	3.1 Cash and cash equivalents Cash and cash equivalents include cash in hand, bank deposits, overdraft accounts and other short-term highly liquid investments with maturities and intention of use by the Company’s Management in a period lower than three months.
Financial assets and liabilities	3.2 Financial assets and liabilities Financial Asset - Classification The Company classified its financial assets according to the following categories: measured at amortized cost, measured at fair value through other comprehensive income and measured at fair value through profit or loss. The classification depends on the purpose for which the financial assets were acquired. Management determines the classification of the financial assets at inception. As of December 31, 2021 and 2020, the Company did not have financial assets classified as fair value through other comprehensive income and fair value through profit or loss. • Amortized cost This comprises financial assets that meet the following conditions: (i) it is held within the business model whose objective is to hold financial assets to collect contractual cash flows; and (ii) the contractual terms of the financial asset give rise, on specified dates, to cash flows that are solely payments of principal and interest on the principal amount outstanding. Presented as current assets, except for those with maturity of more than 12 months after the reporting date (these are classified as noncurrent assets). The Company's financial assets measured at amortized cost include cash and cash equivalents, financial investments, restricted cash, balances of trade receivables, accounts receivable from related parties, other receivables, receivables from the Water and Basic Sanitation National Agency – ANA. Financial assets measured at amortized cost are recorded at fair value and subsequently at amortized cost, under the effective interest rate method, except for trade receivables, which is initially measured at transaction price, as it contains no financing items, and is subsequently measured at amortized cost. Financial Liabilities - Classification The Company classifies its financial liabilities measured at amortized cost. Classification depends on the purpose to which the financial liabilities were assumed. This category comprises balances payable to contractors and suppliers, borrowings and financing, services payable, balances payable from public-private partnership (PPP), and program contract commitments. The effective interest rate method is adopted to calculate the amortized cost of a financial liability and allocate its interest expense under the respective period. The effective interest rate exactly deducts the estimated future cash flows (including fees, transaction costs and other issue costs) throughout the financial liability’s estimated life or, when appropriate, during a shorter period, for initial recognition of the net carrying amount. Impairment of financial assets Trade receivables Due to the charactheristics of the Company’s accounts receivable such as (i) insignificant financial component, (ii) non-complex receivables portfolio, and (iii) low credit risk, the Company adopted the simplified approach of expected credit loss, which consists in recognizing the expected credit loss based on the total asset’s useful life. The methodology to calculate allowance for doubtful accounts consisted of using an estimate calculated based on the average default observed in the last 36 months, per maturity range, in addition to estimating the recovery of credits overdue for more than 360 days, based on the track record of the last three years. For estimate purposes, it also considered the category of private and public customers, and segregated accounts receivable among the regular consumption accounts and agreements. The Company also concluded that the estimates of the macroeconomic indicators Gross Domestic Product (GDP), Unemployment Rate and the Extended Consumer Price Index (IPCA) were not impacted, given that it carried out correlation analyses of these indicators and its default history, which did not result in significant correlation between them. Deposit transactions and financial investments measured at amortized cost The Company analyzes changes in the rates of investments in bank deposits certificates and information obtained from regulatory agencies about the financial institutions. The likelihood of delinquency over 12 months and during the terms of these investments was based on historical data provided by credit rating agencies for each credit level and analyzed in terms of sensitivity based on current returns. These deposits and financial investments are subject to an insignificant risk of change in value.
Operating income	3.3 Operating income (a) Revenue from sanitation services Revenue from water supply and sanitation services are recognized as the water is consumed and services are provided. Revenues, including unbilled revenues, are recognized at the fair value of the consideration received or receivable for the rendering of those services. Revenue is shown net of value-added tax, rebates and discounts. Unbilled revenues represent incurred revenues in which the services were provided, but not yet billed until the end of the each period and are recorded as trade receivables based on monthly estimates of the completed services. Revenues are recognized based on IFRS 15 (Revenue from Contracts with Customers), which establishes a five-step model applicable over revenue from a contract with a customer. Revenues are recognized when the Company: i) it identifies the contracts with customers; ii) it identifies the different obligations in the contract; iii) it determines the transaction price; iv) it allocates the transaction price to the performance obligations in the contracts; and (v) it satisfies all performance obligations. Disputed amounts are recognized as revenue when collected. (b) Construction revenue Revenue from concession construction contracts is recognized in accordance with IFRS 15 (Revenue from Contracts with Customers) and IFRIC 12 (Service Concession Arrengements), as all performance obligations are satisfied over time. During the construction phase of the contract, an asset is classified as contract assets, as the Company estimates that the fair value of its consideration is equivalent to expected construction costs plus margin. The fee represents the additional margin related to the work performed by the Company in relation to such construction contracts and it is added to construction costs, resulting in the construction revenue.
Trade receivables and allowance for doubtful accounts	3.4 Trade receivables and allowance for doubtful accounts Trade receivables are amounts due from customers for services performed in the ordinary course of business. These are classified as current assets, except when maturity exceeds 12 months after the end of the reporting period. In these cases, they are presented as noncurrent assets. The Company establishes an allowance for doubtful accounts for receivable balances at an amount that Management considers to be sufficient to cover eventual losses, as described in note 3.2.
Inventories	3.5 Inventories Inventories comprise supplies for consumption and maintenance of the water and sewage systems are stated at the lower of average cost of acquisition or net realizable value, and are classified in current assets.
Investment properties	3.6 Investment properties Investment properties are recorded at the acquisition or construction cost, less accumulated depreciation, except for the land group, calculated by the straight-line method at rates that consider the estimated useful life of the assets. Expenditures related to repairs and maintenance are recorded in the income statement when incurred. The Company also maintains some assets for undetermined use in the future, i.e. it is not defined if the Company will use these assets in the operation or sell them in the short term during the ordinary course of business.
Contract asset	3.7 Contract asset The Contract Asset (works in progress) is the right to consideration in exchange for goods or services transferred to the customers. As determined by IFRS 15 - Revenue from contract with customer, assets related to the concession under construction, recorded under the scope of IFRIC 12 – Service Concession Arrengements, should be classified as contract asset during the construction period and transferred to the intangible assets only after the completion of the works. A contract asset is initially recognized at fair value and includes construction margin and borrowing costs capitalized in qualifying assets, when applicable, during the period in which the asset is in the construction phase, based on the weighted average rate of borrowings in effect on the capitalization date. A qualifying asset is an asset that necessarily requires a substantial period of time to be ready for its intended use or sale.
Property, plant and equipment	3.8 Property, plant and equipment Property, plant and equipment comprise mainly administrative facilities not composing the assets, subject-matter of the concession agreements. Those assets are stated at historical acquisition or construction cost less depreciation, net of impairment losses, when necessary. Interest, other finance charges and inflationary effects resulting from financing effectively applied to construction in progress are recorded as cost of respective property, plant and equipment, in this case, for the qualifying assets, as applicable. Qualifying assets are assets that, necessarily, required a substantial period to get ready for its intended use or sale. The Company defined that this period is higher than 12 months. Subsequent costs included in the existing asset's carrying amount or recognized as a separate asset, as appropriate, only when it is probable that the future economic benefit associated with the item will flow to the Company and the cost of the item can be reliably measured. Repairs and maintenance are charged to the income statement of the year, as incurred. Depreciation is calculated using the straight-line method to allocate their cost and the average rates are presented in Note 16 (a). Land is not depreciated. Residual values and the useful life of assets are revised and adjusted, where applicable, at the end of each year. Gain and losses on disposals are determined by the difference between the proceeds with the carrying amount and are recognized in other operating income (expenses) in the income statement.
Intangible assets	3.9 Intangible assets Intangibles are stated at acquisition cost and/or construction of the underlying assets, including construction margin, interest and other finance charges capitalized during the construction period, in this case, for the qualifying assets. Qualifying assets are assets that, necessarily, take a substantial period to get ready for its intended use or sale. The Company considers that substantial period means a period greater than 12 months. This period was established by considering the completion period of the majority of its constructions, which is greater than 12 months, which corresponds to one fiscal year of the Company. The intangible has its amortization initiated when the intangible assets are available for use in location and the necessary condition when this asset becomes operational. The amortization of the intangible assets is discontinued when the asset is totally consumed or it is disposed of, whatever occurs first. Donations in assets, received from third parties and governmental entities, to allow the Company to render water and sewage services are recorded in the Company’s financial statements at zero cost, since these assets are controlled by the concession grantor. Financial resources received as donations for the construction of infrastructure are recorded under “Other operating income”. (a) Concession agreements/program contracts/service contracts The Company operates concession agreements including the rendering of basic sanitation, environmental, water supply and sewage services signed with the concession grantor. The infrastructure used by SABESP subject to service concession arrangements is considered to be controlled by the concession grantor when: (i) The grantor controls or regulates what services the operator must provide with the infrastructure, to whom it must provide them, and at what price; and (ii) The grantor controls the infrastructure, i.e., retains the right to take back the infrastructure at the end of the concession. The rights over the infrastructure operated under the concession agreements are accounted for as an intangible asset as the Company has the right to charge for the use of the infrastructure assets, and the users (consumers) have the primary responsibility to pay SABESP for the services. The fair value of construction and other works on the infrastructure is recognized as revenue, as its fair value, when the infrastructure is built, provided that this work is expected to generate future economic benefits. The accounting policy to recognize construction revenue is described in Note 3.3 (b). The details referring to amortization of intangible assets are described in Note 15 (c). (b) Software license of use Software licensing is capitalized based on the acquisition costs and other implementation costs. Amortizations are recorded according to the useful life and the expenses associated with maintaining them are recognized as expenses when incurred.
Impairment of non-financial assets	3.10 Impairment of non-financial assets Property, plant and equipment, intangible assets and other noncurrent assets with defined useful lives, are yearly reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The Company does not have assets with indefinite useful life and assessed that there are no indications of impairment losses, mainly supported by Law 14,026/2020, which ensures that basic sanitation public utilities will have assured its economic and financial sustainability to public sanitation services through tariffs or indemnity.
Trade payables and contractors	3.11 Trade payables and contractors Trade payables and contractors are obligations to pay for goods or services acquired from suppliers in the ordinary course of business and are initially measured at fair value, which generally correspond to the bill and subsequently at amortized cost, being classified as current liabilities, except when the maturity exceeds 12 months after the reporting date and are, otherwise, being presented as noncurrent liabilities.
Borrowings and financing	3.12 Borrowings and financing Borrowings and financing are initially recognized at fair value, upon receipt of funds, net of transaction costs. Subsequently, borrowings and financing are stated at amortized cost, as presented in Note 17. Borrowings and financing are classified as current liabilities unless the Company has an unconditional right to defer the settlement of the liability for at least 12 months after the end of the reporting date. Nonconvertible bonds issued by the Company are recognized in a similar manner to borrowings.
Borrowing costs	3.13 Borrowing costs Borrowing costs attributable to acquisition, construction or production of an asset, which, necessarily, requires a substantial time period to be ready for use or sale are capitalized as part of the cost of these assets. Other borrowing costs are recognized as expenses in the period they are incurred. Borrowing costs are interest rates and other charges incurred by the Company related to borrowings, including exchange variation, as described below. The capitalization occurs during the period in which the asset has been built, considering the weighted average rate of borrowings effective on the capitalization date. For foreign currency-denominated borrowings or financing, the Company analyzes them as if they were contracted in local currency, restricting the capitalization of interest and/or exchange variation by the amount that would be capitalized if these were contracted in the domestic market in similar lines of credit and loans.
Salaries, payroll charges and contributions	3.14 Salaries, payroll charges and contributions Salaries, vacations, Christmas bonus, profit sharing and additional payments negotiated in collective labor agreements plus related charges and contributions are recorded on the accrual basis. The profit sharing plan for its employees is based on operational and financial targets, and a provision is created when it is contractually required or when there is a past practice that created a constructive obligation, and is recorded on the accrual basis period as operating cost, selling and administrative expenses or capitalized in assets.
Provisions, legal obligations, escrow deposits and contingent assets	3.15 Provisions, legal obligations, escrow deposits and contingent assets Provisions related to claims are recognized when: i) the Company has a present (legal or constructive) obligation resulting from a past event; ii) it is probable that an outflow of resources that comprise economic benefits will be required to settle the obligation; and iii) the amount can be reliably estimated. Where there are a number of similar obligations, the likelihood that an outflow of resources will be required to settle an obligation is determined by considering the nature of the obligations as a whole. Provisions are measured at the present value of the disbursements expected to be required to settle the obligation using a pre-tax rate that reflects current market assessments of the time value of money and the risks specific to the obligation. The increase in the provision due to the passage of time is recognized as financial expense. For financial statement presentation purposes, the provision is stated net of escrow deposits, based on the legal offset right. Escrow deposits not linked to the related obligations are recorded in noncurrent assets. Escrow deposits not linked to the related obligations are recorded in noncurrent assets and adjusted by the indexes defined by the competent authorities. The Company does not recognize contingent liabilities in the financial statements since it either does not expect outflows to be required or the amount of the obligation cannot be reliably measured. Contingent assets are not recognized in the statements of financial position.
Environmental costs	3.16 Environmental costs Costs related to ongoing environmental programs are expensed in the income statement, when there is any indication of an event. Ongoing programs are designed to minimize the environmental impact of the operations and to manage the environmental risks inherent to the Company's activities.
Income taxes – current and deferred	3.17 Income taxes – current and deferred Income taxes expenses comprise current and deferred income tax and social contributions. Current taxes The provision for income tax and social contribution is calculated based on the taxable income for the year and the rates effective at the end of the year. The income tax was accrued at rate of 15%, plus 10% surtax on taxable income exceeding R$ 240 9 Deferred taxes Deferred income tax is recognized, using the liability method, on temporary differences arising between the tax basis of assets and liabilities and their carrying amounts in the financial statements. However, the deferred income tax is not accounted for if it arises from initial recognition of an asset or liability in a transaction that at the time of the transaction affects neither accounting nor taxable profit nor loss, except for business combinations. Deferred income tax is determined using tax rates (and laws) effective at the end of the reporting period and expected to apply when the related deferred income tax asset is realized or the deferred income tax liability is settled. Deferred income tax and social contribution assets are recognized only to the extent that it is probable that future taxable profit will be available for which temporary differences can be utilized and tax losses can be carryforward. Deferred taxes assets and liabilities are offset when there is a legally enforceable right of offsetting current tax assets against current tax liabilities and when deferred income tax assets and liabilities are related to income taxes levied by same tax authority over the tax entity.
Taxes on revenues	3.18 Taxes on revenues Revenues from sanitation services are recognized on accrual basis for PASEP (Programa de Formação do Patrimônio do Servidor Público) and Cofins (Contribuição para o Financiamento da Seguridade Social), calculated at the rates of 1.65 7.60 The taxes related to PASEP and Cofins incident on amounts invoiced to public entities are due when invoices are received. These taxes are calculated by the non-cumulativeness regime and presented net, as deductions from gross revenues. Tax debts calculated over “other operating income” are presented as deductions from the respective operating income. In addition, revenues from sanitation services are also subject to the Regulatory, Control and Oversight Fee (TRCF - Taxa de Regulação, Controle e Fiscalização), whose taxable event is the performance of regulatory, control and monitoring activities by ARSESP, calculated at 0.50
3.19 Pension plan obligations	3.19 Pension plan obligations (a) Defined benefit The Company makes contributions to defined benefit plans on a contractual basis and sponsored thereby. The regular contributions comprise the net administrative expenses and are recognized in the income statement for the period. Liabilities from defined benefit pension plan obligations correspond to the present value of the defined benefit obligation at the end of the reporting period, less the fair value of the plan’s assets. The defined benefit obligation (G1) and (G0) are calculated on an annual basis by independent actuaries, using the projected unit credit method. The estimated future cash outflow is discounted to its present value, using the interest rates of Government bonds with maturities that approximate the maturity of the related liability. Referring to actuarial gains and losses deriving from adjustments based on the experience and changes in actuarial assumptions are directly recorded under equity, as other comprehensive income (OCI), so that the plan's net assets or liabilities are recognized in the statement of financial position in order to reflect the full amount of plan’s deficit or surplus. In an event where a curtailment relates to only some of the employees covered by a plan, or where only part of an obligation is settled, the gain or loss includes a proportionate share of the past service cost and actuarial gains and losses. The proportionate share is determined on the basis of the present value of the obligations before and after the curtailment or settlement. (b) Defined contribution The Company makes contributions to defined contribution plans on a contractual basis and sponsored thereby, a supplementary private pension entity that provides post-employment benefits to its employees, in which the Company makes fixed and equal contributions to employees, within the limits set by regulation. In this model, the benefits paid are directly related to the amount contributed, with no deficits to be covered by the Company.
Financial revenues and expenses	3.20 Financial revenues and expenses Financial revenue is primarily comprised of interest and inflation adjustments resulting from financial investments, escrow deposits and negotiations with customer to pay by installments, calculated using the effective interest rate method. Financial expenses are primarily comprised of interest, inflation adjustments and exchange rate changes on borrowings and financing, provisions, public-private partnership and program contract commitments. These financial income and expenses are calculated using the effective interest rate method. Inflation adjustments and exchange gains and losses derive from the collection or payment to third parties, as contractually required by law or court decision, and recognized on an accrual basis pro rata temporis. Inflation adjustments included in the agreements are not considered embedded derivatives, since they are deemed as inflation adjustment rates for the Company’s economic scenario.
Leases	3.21 Leases Leases are recognized at the present value of the contractual obligations, presented in assets as Right of Use (Note 15 (j)) and in liabilities as Leases (Note 17 (b)), except for short-term contracts (12 months or less) and/or low value (below US$ 5 thousand), which are recorded in the income statement recognized as an expense when incurred.
Other current and noncurrent assets and liabilities	3.22 Other current and noncurrent assets and liabilities Other assets are stated at acquisition cost, net of any impairment loss, where applicable. The amounts recognized as other liabilities are stated at known or estimated amounts, including, where applicable, related charges and inflation adjustments.
Dividends and interest on capital	3.23 Dividends and interest on capital The Company uses the tax benefits of distributing dividends as interest on capital, as permitted by Brazilian Law and based on the Bylaws. This distribution of dividend is accounted for in accordance with Brazilian Law 9,249/95 for tax deductibility purposes, limited to the daily pro rata fluctuation of the Long-term Interest Rate (TJLP). The benefit attributed to the shareholders is recognized in the current liability against Equity, based on its by-laws. Dividends and interest on capital over the minimum established in the by-laws are recognized when approved by the shareholders in the shareholders’ meeting, except for taxes incurring in the distribution of interest on capital. The tax benefit of the interest on capital is accrued in the income statement of the year, under the same recognition basis of expenses with interest on capital.
Present value adjustment	3.24 Present value adjustment Current and noncurrent financial assets and liabilities arising from long- or short-term transactions are adjusted to present value based on market discount rates as of the transaction date, when the effects are significant.
Segment information	3.25 Segment information Operating segments are determined in a manner consistent with the internal reporting to the Company’s chief operating decision maker (“CODM”), which, in the case of SABESP, is comprised of the Board of Directors and Board of Executive Officers, to make strategic decisions, allocate resources and evaluate performance. Consequently, the Company determined that it has one operating segment which is sanitation services. The accounting policies used to determine segment information are the same as those used to prepare the Company’s financial statements. The measure of the segment’s profit or loss is operating income before other operating expenses, net and equity accounting, which excludes construction revenue and related costs. The CODM analyzes asset and liabilitity information on a consolidated basis. Consequently, the Company does not disclose segment information on assets and liabilities. Substantially all of the Company’s noncurrent assets and revenue generated from customers are located in São Paulo State. Consequently, financial information is not disclosed by geographic area.
Translation into foreign currency	3.26 Translation into foreign currency (a) Functional and reporting currency Items included in the financial statements are measured using the currency of the primary economic environment in which the company operates ("the functional currency"). The financial statements are presented in Brazilian reais (R$), which is also the Company's functional currency. All financial information has been stated in reais and rounded to the next thousand, except where otherwise indicated. (b) Foreign currency translation Foreign currency-denominated transactions are translated into Brazilian reais using the exchange rates prevailing at the transaction dates. Statement of financial position accounts are translated by the exchange rate prevailing at reporting date. Exchange gains and losses resulting from the settlement of these transactions and the translation of foreign currency-denominated cash assets and liabilities are recognized in the income statement, except for borrowings and financing referring to property, plant and equipment or intangible assets in progress, where exchange losses are recognized as corresponding entry to the asset while construction is in progress, as described in Note 3.12.

Operations (Tables)

Operations (Tables)	12 Months Ended
	Dec. 31, 2021
Operations
The table below shows a summary of the contractual situation of the municipalities served:	The table below shows a summary of the contractual situation of the municipalities served: December 31, 2021 December 31, 2020 Total municipalities that have already signed contracts 342 342 Balance – intangible and contract assets 42,260,091 39,440,568 Percentage of intangible and contract assets 93.80% 93.08% Revenue from sanitation services (excluding construction revenue) 15,490,808 14,406,803 Percentage of revenue from sanitation services (excluding construction revenue) 95.01% 95.05% Municipalities with expired contracts: 8 8 Balance – intangible and contract assets 214,329 264,931 Percentage of intangible and contract assets 0.48% 0.63% Revenue from sanitation services (excluding construction revenue) 41,194 39,088 Percentage of revenue from sanitation services (excluding construction revenue) 0.25% 0.26% Municipalities with concession agreements due by 2030: 25 25 Balance – intangible and contract assets 1,127,920 1,436,529 Percentage of intangible and contract assets 2.50% 3.39% Revenue from sanitation services (excluding construction revenue) 653,408 597,483 Percentage of revenue from sanitation services (excluding construction revenue) 4.01% 3.94% Municipality of São Paulo: Percentage of intangible and contract assets 43.11% 37.94% Percentage of revenue from sanitation services (excluding construction revenue) 44.45% 44.58%

Changes in accounting practic_2

Changes in accounting practices and disclosures (Tables)	12 Months Ended
	Dec. 31, 2021
New standards and revisions	New standards and revisions Standard Description Impact Amendments to IFRS 4 – Insurance Contracts, IFRS 7 – Financial Instruments: Disclosures, IFRS 9 – Financial Instruments, IFRS 16 – Leases Describes the amendments to the Reference Interest Rate Reform – Phase 2. The adoption of these amendments reflects the effects of the transition from interbank offered rates (“IBOR”) to alternative reference interest rates (also called interest-free rates risk or “risk free rates – RFRs”). The application of these amendments did not impact the disclosures or amounts recognized in the annual financial statements. Amendment to IFRS 16 – COVID-19 - Related Rent Concessions Establishes practical measures for lessees in the accounting for lease concessions that occurred as a direct result of COVID-19. Under the practical expedient, a lessee is not required to assess whether a COVID-19-related lease concession is a lease modification. The application of this amendment did not impact the disclosures or amounts recognized in the annual financial statements.
The Company did not early adopt these standards and is assessing the impacts of the new and revised IFRS below on the disclosures or amounts recognized in the financial statements:	The Company did not early adopt these standards and is assessing the impacts of the new and revised IFRS below on the disclosures or amounts recognized in the financial statements: Standard Description Impact IFRS 17 – Insurance Contracts 2 Establishes the principles for the recognition, measurement, presentation and disclosure of insurance contracts. IFRS 17 will supersede IFRS 4 Insurance Contracts. The Company does not expect effects from adopting this standard. Amendments to IFRS 10 - Consolidated Statements and IAS 28 – Sale or Contribution of Assets between an Investor and its Associate or Joint Venture 3 Clarify situations that involve the sale or contribution of assets between an investor and its associates or joint venture. The Company is assessing the impacts and effects of the amendments; however, it does not expect any effects from the amendments. Amendments to IAS 1 – Classification of Liabilities as Current or Non-Current 2 These amendments to IAS 1 only affect the presentation of liabilities as current or non-current in the statement of financial position and not the amount or the time of recognition of any asset, liability, income or expense, or the information disclosed on such items. In addition, clarify that the classification of liabilities as current or non-current is based on the rights existing at the balance sheet date, specify that the classification is not affected by the expectations on whether an entity will exercise its right to postpone the settlement of the liability and introduce the definition of 'settlement' to clarify that settlement refers to the transfer to a counterparty, of cash, equity instruments, other assets or services. The Company does not expect any impacts from this standard. Amendments to IFRS 3 – Reference to the Conceptual Framework 1 The amendments update IFRS 3 so that it refers to the 2018 Conceptual Framework, not to the 1989 Framework. The amendments also include in IFRS 3 the requirement that, for obligations within the scope of IAS 37, the acquirer applies this standard to identify whether there is an obligation at the acquisition date arising from past events. For a tax within the scope of IFRIC 21 - Taxes, the acquirer applies IFRIC 21 to determine whether the event that resulted in the obligation to pay the tax occurred up to the date of acquisition date. Finally, the amendments add an explicit statement that the acquirer does not recognize contingent assets acquired in a business combination. The Company does not expect effects from this standard. Standard Description Impact Amendments to IAS 16 – Proceeds Before Intended Use 1 The amendments prohibit deducting from the cost of an item of property, plant and equipment any proceeds from the sale of items produced before the asset is available for use, i.e. proceeds to bring the asset to the location and in the condition necessary for it to be able to operate as intended by the Company. Consequently, the entity recognizes these proceeds from the sale and corresponding costs in the result and measures the costs of these items in accordance with IAS 2 - Inventories. The Company does not expect effects from this standard. Standard Description Impact Amendments to IAS 37 – Onerous Contracts – Cost of Compliance with the Contract 1 The amendments specify that the contract's "compliance cost" comprises costs directly related to the contract, which are the incremental costs of compliance with that contract (such as employees or materials) and the allocation of other costs directly related to contract compliance (such as allocation of depreciation expenses for an item of property, plant and equipment used in fulfilling the contract). The Company does not expect effects from this standard. Amendments to IAS 1 – Presentation of Financial Statements and IFRS Practice Statement 2 – “Making Materiality Judgments” – Disclosure of Accounting Policies 4 The amendments modify the requirements contained in IAS 1 regarding the disclosure of accounting policies. The amendments replace all the examples of the term “significant accounting policies” with “relevant accounting policy information”. Accounting policy information is material if, when considered together with other information included in an entity's financial statements, it could reasonably influence the decisions of key users of general purpose financial statements made on the basis of those financial statements. The supporting paragraphs have also been amended to clarify that accounting policy information relating to non-important transactions, other events or conditions is immaterial and need not be disclosed. The Company does not expect effects from these amendments. Standard Description Impact Amendments to IAS 8 - Accounting Policies, Changes in Accounting Estimates and Errors—Definition of Accounting Estimates 2 The amendment supersede the definition of change in accounting estimates with the definition of accounting estimates. According to the new definition, accounting estimates are “monetary amounts in the financial statements subject to measurement uncertainty”. The Company does not expect effects from these amendments. Amendments to IAS 12 – Income Taxes – Deferred Tax Related to Assets and Liabilities Resulting from a Single Transaction (“single transaction”) 2 The amendments introduce an additional exception to the exemption of first-time recognition. According to the amendments, an entity does not apply the exemption of first-time recognition for transactions resulting in equal taxable and deductible temporary differences. The Company does not expect effects from these amendments. Standard Description Impact Annual improvements to IFRSs: 2018-2020 Cycle Amendments to IFRS 1 – First-time Adoption of International Financial Reporting Standards 1 1 1 IFRS 1 – First-Time Adoption of International Accounting Standards - provides for an additional measure for a subsidiary that becomes an initial adopter after its parent company with respect to accounting for accumulated translation differences. The Company does not expect effects from these amendments. 1 Effective for annual periods beginning on or after January 1, 2022. 2 Effective for annual periods beginning on or after January 1, 2023. 3 The effective date of the amendments has not yet been defined by IASB. 4 The amendments to IFRS Practice Statement 2 do not have an effective date or transition requirements.

Risk Management (Tables)

Risk Management (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of exposure to exchange risk	Schedule of exposure to exchange risk December 31, 2021 December 31, 2020 Foreign currency (in thousands) R$ Foreign currency (in thousands) R$ Borrowings and financing – US$ 163,538 912,624 167,479 870,338 Borrowings and financing – Yen 49,324,813 2,390,774 52,969,560 2,671,255 Interest and charges from borrowings and financing – US$ 4,121 5,540 Interest and charges from borrowings and financing – Yen 13,970 16,037 Total exposure 3,321,489 3,563,170 Borrowing cost – US$ (22,486) (12,342) Borrowing cost – Yen (2,850) (2,966) Total foreign-currency denominated borrowings (Note 17) 3,296,153 3,547,862
The table below shows the exchange rate variation for the period:	The table below shows the exchange rate variation for the period: December 31, 2021 December 31, 2020 Variation US$ R$ 5.5805 R$ 5.1967 7.4 Iene R$ 0.04847 R$ 0.05043 -3.9
The Company understands that the scenario presented is reasonable, given the instability of the Brazilian real against the U.S. dollar and the Yen.	The Company understands that the scenario presented is reasonable, given the instability of the Brazilian real against the U.S. dollar and the Yen. Scenario I (Probable) (*) Net currency exposure as of December 31, 2021 in US$ - Liabilities 163,538 US$ rate as of December 31, 2021 5.5805 Exchange rate estimated according to the scenario 5.6000 Difference between the rates ( 0.0195 Effect on the net financial result R$ - gain/(loss) (3,189) Net currency exposure as of December 31, 2021 in Yen - Liabilities 49,324,813 Yen rate as of December 31, 2021 0.04847 Exchange rate estimated according to the scenario 0.05093 Difference between the rates (0.00246) Effect on the net financial result R$ - gain/(loss) (121,339) Total effect on the net financial result in R$ - gain/(loss) (124,528)
The table below provides the Company's borrowings and financing subject to variable interest rates:	The table below provides the Company's borrowings and financing subject to variable interest rates: December 31, 2021 December 31, 2020 CDI (i) 7,612,299 7,836,988 TR (ii) 1,638,079 1,619,416 IPCA (iii) 3,019,459 2,176,547 TJLP (iv) 1,478,740 1,517,657 LIBOR (v) 912,626 870,337 Interest and charges 243,696 164,439 Total 14,904,899 14,185,384 (i) CDI – (Certificado de Depósito Interbancário), an interbank deposit certificate (ii) TR – Interest Benchmark Rate (iii) IPCA – (Índice Nacional de Preços ao Consumidor Amplo), a consumer price index (iv) TJLP – (Taxa de Juros a Longo Prazo), a long-term interest rate index (v) LIBOR – London Interbank Offered Rate
For the credit quality of the banks, such as deposits and financial investments, the Company considers the lower rating published by three main international rating agencies (Fitch, Moody's and S&P), according to internal policy of market risk management:	Regarding the financial assets held with financial institutions, the credit quality was assessed by reference to external credit ratings (if available) or to historical information about the bank’s default rates. For the credit quality of the banks, such as deposits and financial investments, the Company considers the lower rating published by three main international rating agencies (Fitch, Moody's and S&P), according to internal policy of market risk management: Banks Fitch Moody's Standard Poor's Banco do Brasil S/A AA(bra) AAA.br - Banco Santander Brasil S/A - AAA.br brAAA Brazilian Federal Savings Bank AA(bra) AAA.br brAAA Banco Bradesco S/A AAA(bra) AAA.br brAAA Itaú Unibanco Holding S/A AAA(bra) AAA.br brAAA Banco BV - AA.br brAAA Banco BTG Pactual S/A AA(bra) AAA.br brAA+
The table below shows the rating assessment released by the Fitch agency, for deposit transactions and financial investments in local currency (R$ - domestic rating):	The table below shows the rating assessment released by the Fitch agency, for deposit transactions and financial investments in local currency (R$ - domestic rating): December 31, 2021 December 31, 2020 Cash and cash equivalents and financial investments AA(bra) 1,905,810 2,662,685 AAA(bra) 970,474 891,243 Other (*) 275,030 253,619 3,151,314 3,807,547 (*) This category includes current accounts and financial investmets in banks referring to Banco BV in the amount of R$ 262,465 253,066
For agreements with floating interest rate, the interest rates used correspond to the base dates above.	The table below shows the financial liabilities of the Company, by relevant maturities, including the installments of principal and future interest to be paid according to the agreement. Future interest was calculated based on the contractual clauses for all agreements. For agreements with floating interest rate, the interest rates used correspond to the base dates above. 2022 2023 2024 2025 2026 2027 onwards Total As of December 31, 2021 Liabilities Borrowings and financing 2,767,867 2,749,335 2,939,155 2,976,535 2,721,792 12,484,891 26,639,575 Trade payables and contractors 236,763 — — — — — 236,763 Services payable 469,027 — — — — — 469,027 Public-Private Partnership – PPP 429,942 430,440 379,684 351,586 351,586 4,068,466 6,011,704 Program Contract Commitments 77,465 36,442 1,126 1,126 1,126 12,983 130,268
The purpose of the sensitivity analysis is to measure the impact of changes in the market over the financial instruments, considering constant all other variables. In the time of settlement the amounts can be different from those presented, due to the estimates used in the measurement.	The purpose of the sensitivity analysis is to measure the impact of changes in the market over the financial instruments, considering constant all other variables. In the time of settlement the amounts can be different from those presented, due to the estimates used in the measurement. December 31, 2021 Indicators Exposure Scenario I (Probable) Assets CDI 1,533,614 11.79 (**) Financial income 180,813 Liabilities CDI (7,612,299) 11.79 (**) Interest to be incurred (897,490) CDI net exposure (6,078,685) (716,677) Liabilities TR (1,638,079) 0.0276 (**) Expenses to be incurred (452) IPCA (3,019,459) 5.0302 (*) Expenses to be incurred (151,885) TJLP (1,478,740) 6.4400 (***) Interest to be incurred (95,231) LIBOR (912,626) 0.536 (**) Interest to be incurred (4,892) Total expenses to be incurred, net (969,137) (*) Source: Focus-BACEN Report of December 31, 2021 (**) Source: B3 of December 31, 2021 (***) Source: LCA Consultores of December 31, 2021
Total capital is calculated as total equity as shown in the statement of the financial position plus net debt.	Capital is monitored based on the leverage ratio, which corresponds to net debt divided by total capital (shareholders and providers of capital). Net debt corresponds to total borrowings and financing less cash and cash equivalents and financial investments. Total capital is calculated as total equity as shown in the statement of the financial position plus net debt. December 31, 2021 December 31, 2020 Total borrowings and financing (Note 17) 17,723,836 17,258,624 (-) Cash and cash equivalents (Note 7) (717,929) (396,401) (-) Financial investments (Note 8) (2,433,385) (3,411,146) Net debt 14,572,522 13,451,077 Total equity 24,931,859 22,793,704 Total capital (shareholders + providers of capital) 39,504,381 36,244,781 Leverage ratio 37 37
The estimated fair values of the financial instruments are as follows:	The estimated fair values of the financial instruments are as follows: Financial assets December 31, 2021 December 31, 2020 Carrying amount Fair value Carrying amount Fair value Cash and cash equivalents 717,929 717,929 396,401 396,401 Financial investments 2,433,385 2,433,385 3,411,146 3,411,146 Restricted cash 28,467 28,467 35,742 35,742 Trade receivables 2,918,311 2,918,311 2,450,986 2,450,986 Water and Basic Sanitation National Agency – ANA 20,666 20,666 26,463 26,463 Other assets 226,242 226,242 246,110 246,110
Financial liabilities	Financial liabilities December 31, 2021 December 31, 2020 Carrying amount Fair value Carrying amount Fair value Borrowings and financing 17,723,836 17,947,954 17,258,624 17,702,649 Trade payables and contractors 236,763 236,763 263,741 263,741 Services payable 469,027 469,027 453,750 453,750 Program contract commitments 122,647 122,647 231,480 231,480 Public-Private Partnership - PPP 3,060,185 3,060,185 3,175,273 3,175,273

Cash and cash equivalents (Tabl

Cash and cash equivalents (Tables)	12 Months Ended
	Dec. 31, 2021
Cash and cash equivalents	Cash and cash equivalents December 31, 2021 December 31, 2020 Cash and banks 146,853 74,033 Cash equivalents 571,076 322,368 Total 717,929 396,401

Financial investments (Tables)

Financial investments (Tables)	12 Months Ended
	Dec. 31, 2021
The Company has financial investments in CDB, with daily liquidity, which it does not intend to use in the next three months, as shown below:	The Company has financial investments in CDB, with daily liquidity, which it does not intend to use in the next three months, as shown below: December 31, 2021 December 31, 2020 Banco BV 262,465 253,066 Banco Itaú S/A 366,906 354,296 Banco Bradesco S/A 524,791 506,136 Banco BTG Pactual S/A 367,361 354,299 Banco do Brasil S/A 911,862 1,943,349 2,433,385 3,411,146

Restricted cash (Tables)

Restricted cash (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of restricted cash	Schedule of restricted cash December 31, 2021 December 31, 2020 Agreement with the São Paulo municipal government (i) 21,464 29,599 Brazilian Federal Savings Bank – escrow deposits (ii) 740 272 Other 6,263 5,871 28,467 35,742 (i) Refers to the amount deducted from the transfer 7.5% of the revenue earned in the municipality to the Municipal Fund for Environmental Sanitation and Infrastructure, corresponding to eventual amounts unpaid by direct management bodies, foundations and government agencies, as established in the agreement entered into with the municipal government of São Paulo; and (ii) Refers to the savings account intended to receive escrow deposits from lawsuits with final and unappealable decisions in favor of the Company, which are blocked under the contractual clause.

Trade receivables (Tables)

Trade receivables (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of financial position	Schedule of financial position December 31, 2021 December 31, 2020 Private sector: General (i) (ii) 2,042,023 1,663,738 Agreements (iii) 514,616 398,367 2,556,639 2,062,105 Government entities: Municipal 586,810 473,201 Federal 7,869 3,859 Agreements (iii) 278,844 333,740 873,523 810,800 Wholesale customers – Municipal governments: (iv) Mogi das Cruzes 3,580 3,582 São Caetano do Sul 24,464 18,808 Total wholesale customers – Municipal governments 28,044 22,390 Unbilled supply 740,193 713,310 Subtotal 4,198,399 3,608,605 Allowance for doubtful accounts (1,280,088) (1,157,619) Total 2,918,311 2,450,986 Current 2,695,077 2,204,029 Noncurrent 223,234 246,957 2,918,311 2,450,986 (i) General customers - residential and small and mid-sized companies; (ii) Special customers - large consumers, commercial, industries, condominiums and special billing customers (fixed demand agreements, industrial waste, wells, among others); (iii) Agreements - installment payments of past-due receivables, plus monetary adjustment and interest, according to the agreements; (iv) Wholesale basis customers - municipal governments - This balance refers to invoices issued as a result of services provided to municipalities, which are responsible for distributing to, billing and charging final customers.
Schedule of aging of trade receivables	(b) The aging of trade receivables is as follows Schedule of aging of trade receivables December 31, 2021 December 31, 2020 Current 1,896,535 1,793,104 Past-due: Up to 30 days 502,164 340,760 From 31 to 60 days 267,723 177,103 From 61 to 90 days 182,977 120,488 From 91 to 120 days 155,018 88,323 From 121 to 180 days 258,718 113,060 From 181 to 360 days 95,751 82,365 Over 360 days 839,513 893,402 Total past-due 2,301,864 1,815,501 Total 4,198,399 3,608,605
Schedule of allowance for doubtful accounts	(c) Allowance for doubtful accounts Schedule of allowance for doubtful accounts December 31, 2021 December 31, 2020 December 31, 2019 Balance at beginning of the year 1,157,619 1,042,015 1,099,442 Additions 182,547 176,776 54,064 Recoveries (60,078) (61,172) (111,491) Balance at the end of the year 1,280,088 1,157,619 1,042,015
Schedule of reconciliation of estimated/historic losses of income	Schedule of reconciliation of estimated/historic losses of income Reconciliation of estimated/historical losses of income December 31, 2021 December 31, 2020 December 31, 2019 Write-offs (508,055) (329,512) (179,929) (Losses)/reversal with state entities - related parties (13,206) 290 (5,597) (Losses) with the private sector / government entities (182,547) (176,776) (54,064) Recoveries 60,078 61,172 111,491 Amount recorded expense (Note 29) (643,730) (444,826) (128,099)

Related-Party Balances and Tr_2

Related-Party Balances and Transactions (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of loan agreement through credit facility	Schedule of accounts receivable, interest on capital payable, revenue and expenses with Sao Paulo December 31, 2021 December 31, 2020 Accounts receivable Current: Sanitation services (i) 127,614 109,078 Allowance for losses (i) (52,333) (39,127) Reimbursement for retirement and pension benefits paid (G0): - monthly flow (payments) (ii) and (vi) 11,930 22,726 - GESP Agreement – 2015 (iv) 86,446 75,377 Total current 173,657 168,054 Noncurrent: Agreement for the installment payment of sanitation services 1,361 4,303 Reimbursement of additional retirement and pension benefits paid (G0): - GESP Agreement – 2015 (iv) 643,534 634,288 Total noncurrent 644,895 638,591 Total receivables from shareholders 818,552 806,645 Assets: Sanitation services 76,642 74,254 Reimbursement of additional retirement and pension benefits (G0) 741,910 732,391 Total 818,552 806,645 Liabilities: Interest on capital payable to related parties 275,240 116,180 Schedule of loan agreement through credit facility 2021 2020 2019 Revenue from sanitation services 522,608 501,756 556,574 Payments received from related parties (439,349) (520,881) (546,365) Payment received from reimbursement referring to Law 4,819/58 (179,787) (173,874) (152,112)
Schedule of loan agreement through credit facility	Schedule of loan agreement through credit facility 2021 2020 2019 Revenue from sanitation services 522,608 501,756 556,574 Payments received from related parties (439,349) (520,881) (546,365) Payment received from reimbursement referring to Law 4,819/58 (179,787) (173,874) (152,112)

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of the investees' financial statements and equity interest	Schedule of the investees' financial statements and equity interest Company Equity Dividends distributed Profit (loss) for the year 2021 2020 2019 2021 2021 (*) 2020 2019 Sesamm 58,421 51,514 45,923 (2,152) 9,059 — 7,332 4,418 Águas de Andradina 29,591 29,576 30,065 (2,320) 2,424 (89) 778 7,271 Águas de Castilho 9,384 8,533 7,242 (592) 1,428 15 1,613 1,767 Saneaqua Mairinque¹ — 4,013 4,783 — — — (770) (871) Attend Ambiental 23,493 11,409 7,486 — 4,701 7,383 3,923 (18,217) Aquapolo Ambiental 58,172 41,903 37,772 (9,000) 25,269 — 19,131 16,283 Paulista Geradora de Energia 6,153 6,692 7,144 — (539) — (452) (481) Company Investments Dividends distributed Other Comprehensive Income Reclassification Equity in the earnings of subsidiaries Interest percentage 2021 2020 2021 2020 2020 2021 (*) 2020 2019 2021 2020 2019 Sesamm 21,032 18,546 (775) — — 3,261 — 2,640 1,591 36 36 36 Águas de Andradina 8,877 8,873 (696) — — 727 (27) 233 2,181 30 30 30 Águas de Castilho 2,815 2,560 (178) — — 429 4 485 529 30 30 30 Saneaqua Mairinque² — — — 17 (1,203) — — (248) (262) 4,6 4,6 30 Attend Ambiental 10,572 5,134 — — — 2,116 3,322 1,765 (8,198) 45 45 45 Aquapolo Ambiental 28,504 20,532 (4,410) — — 12,382 — 9,374 7,979 49 49 49 Paulista Geradora de Energia 1,538 1,673 — — — (135) — (113) (119) 25 25 25 Total 73,338 57,318 (6,059) 17 (1,203) 18,780 3,299 14,136 3,701 Other investments 6,099 6,099 Overall total 79,437 63,417 (*) Refer to changes in the equity of investees, as their financial statements for the year ended December 31, 2020 were issued, including some adjustments, after the Company’s financial statements. (¹) The amounts presented for 2020 refer to July 31, 2020. (²) On August 20, 2020, the investee Saneaqua Mairinque held an Extraordinary Shareholders' Meeting that approved a capital increase in the amount of R$ 21,944 17,178,988 5,734

Investment properties (Tables)

Investment properties (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of investment properties	Schedule of investment properties December 31, 2020 Write-offs and disposals Depreciation December 31, 2021 Investment properties 46,274 (100) (48) 46,126 December 31, 2019 Transfers Depreciation December 31, 2020 Investment properties 47,562 (1,240) (48) 46,274 December 31, 2018 Transfers Depreciation December 31, 2019 Investment properties 47,620 (9) (49) 47,562

Contract assets (Tables)

Contract assets (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of contract assets	Schedule of contract assets December 31, 2020 Additions (i) Transfers Transfers of works to intangible assets (ii) December 31, 2021 (iii) Total contract assets 7,969,164 4,759,789 2,412 (4,181,263) 8,550,102 (i) The largest additions of the period are located in the municipalities of São Paulo, Guarulhos and Praia Grande, in the amounts of R$ 2,419 million, R$ 180 million and R$ 158 million, respectively. (ii) The largest transfers of the period are located in the municipalities of São Paulo, Itaquaquecetuba and São Bernardo do Campo, in the amounts of R$ 2,270 million, R$ 199 million and R$ 180 million, respectively. (iii) The largest works are located in the municipalities of São Paulo, Praia Grande and São Bernardo do Campo, in the amounts of R$ 3,955 million, R$ 634 million and R$ 407 million, respectively. As of December 31, 2021, contract assets include leases recognized before December 31, 2019 in accordance with IAS 17 amounting to R$ 276,893 276,893 December 31, 2019 Additions (i) Transfers Transfers of works to intangible assets (ii) December 31, 2020 (iii) Total contract assets 7,617,714 3,984,158 55,706 (3,688,414) 7,969,164 December 31, 2018 Additions Write-offs Transfers Transfers of works to intangible assets December 31, 2019 Total contract assets 7,407,948 3,532,283 (4,910) 10,710 (3,328,317) 7,617,714

Intangible assets (Tables)

Intangible assets (Tables)	12 Months Ended
	Dec. 31, 2021
Statement of financial position details	(a) Statement of financial position details December 31, 2021 December 31, 2020 Cost Accumulated amortization Net Cost Accumulated amortization Net Intangible right arising from: Concession agreements – equity value 696,728 (205,671) 491,057 671,904 (188,129) 483,775 Concession agreements – economic value 1,497,968 (816,527) 681,441 1,446,261 (711,596) 734,665 Program contracts 24,804,170 (7,652,149) 17,152,021 23,160,119 (6,799,812) 16,360,307 Program contracts – commitments 1,709,757 (391,800) 1,317,957 1,709,757 (338,834) 1,370,923 Services contracts – São Paulo 22,834,803 (6,676,032) 16,158,771 20,579,676 (5,707,072) 14,872,604 Software license of use 1,133,833 (535,099) 598,734 978,085 (437,460) 540,625 Right of use – other assets 173,715 (69,862) 103,853 141,782 (99,106) 42,676 Total 52,850,974 (16,347,140) 36,503,834 48,687,584 (14,282,009) 34,405,575
The obligations assumed by the Company as of December 31, 2021 and 2020 are shown in the table below:	(b) Changes December 31, 2020 Addition Transfer of contract assets Transfers Write-offs and disposals Amortization December 31, 2021 Intangible right arising from: Concession agreements – equity value (*) 483,775 — 24,656 467 (148) (17,693) 491,057 Concession agreements – economic value 734,665 — 52,275 (14) (242) (105,243) 681,441 Program contracts (*) 16,360,307 17,690 1,640,733 13,744 (8,840) (871,613) 17,152,021 Program contracts – commitments 1,370,923 — — — — (52,966) 1,317,957 Services contracts – São Paulo 14,872,604 14,950 2,307,851 (13,827) (13,745) (1,009,062) 16,158,771 Software license of use 540,625 — 155,748 — — (97,639) 598,734 Right of use – Other assets 42,676 140,321 — — (4,103) (75,041) 103,853 Total 34,405,575 172,961 4,181,263 370 (27,078) (2,229,257) 36,503,834 (*) As of December 31, 2021, intangible assets include leases recognized before December 31, 2018 in accordance with IAS 17 amounting to R$ 245,681 65,012 180,669 269,561 76,454 193,107 December 31, 2019 Addition Contract renewal Transfer of contract assets Transfers Write-offs and disposals Amortization December 31, 2020 Intangible right arising from: Concession agreements – equity value (*) 1,494,853 1 (1,031,830) 47,154 1,440 (858) (26,985) 483,775 Concession agreements – economic value 712,852 — — 113,320 (1,403) (42) (90,062) 734,665 Program contracts (*) 13,819,700 303,472 1,031,830 2,075,268 (51,570) (5,423) (812,970) 16,360,307 Program contracts – commitments 1,364,875 58,323 — — — — (52,275) 1,370,923 Services contracts – São Paulo 14,390,763 20,940 — 1,382,656 (23,645) (9,990) (888,120) 14,872,604 Software license of use 471,706 — — 70,016 78,169 — (79,266) 540,625 Right of use – Other assets 70,698 28,549 — — — — (56,571) 42,676 Total 32,325,447 411,285 — 3,688,414 2,991 (16,313) (2,006,249) 34,405,575 (*) As of December 31, 2020, intangible assets includes leases recognized before December 31, 2018 in accordance with IAS 17 amounting to R$ 269,561 76,454 193,107 292,824 87,266 205,558 December 31, 2018 First-time adoption of IFRS 16 Addition Contract renewal Transfer to indemnities receivable Transfer of contract assets Transfers Write-offs and disposals Amortization December 31, 2019* Intangible right arising from: Concession agreements – equity value (*) 4,073,344 — 2 (2,690,660) (4,345) 131,809 76,804 (8,311) (83,790) 1,494,853 Concession agreements – economic value 1,232,009 — 2,034 (532,173) — 89,041 1,956 (569) (79,446) 712,852 Program contracts (*) 8,777,929 — 1,338,443 3,223,773 — 970,534 137,283 (10,312) (617,950) 13,819,700 Program contracts – commitments 1,079,551 — 331,328 — — — — — (46,004) 1,364,875 Services contracts – São Paulo 13,391,452 — 3,867 (940) — 2,054,940 (228,583) (20,739) (809,234) 14,390,763 Software license of use 458,175 — — — — 81,993 (991) — (67,471) 471,706 Right of use – Other assets — 64,955 48,278 — — — — — (42,535) 70,698 Total 29,012,460 64,955 1,723,952 — (4,345) 3,328,317 (13,531) (39,931) (1,746,430) 32,325,447 (*) As of December 31, 2019, intangible assets includes leases recognized before December 31, 2018 in accordance with IAS 17 amounting to R$ 292,824 315,717 98,077 217,640 As of June 30, 2020, a contract was signed for the provision of treatment services and final disposal of solid waste and collection of garbage tax in the Municipality of Diadema for 40 years. In order to reach the best operationalization format, treatment services and final disposal of solid waste are in the study phase and, based on contractual provision, are subject to a partnership between SABESP and a private party, which will occur by means of a public call. (c) Intangible arising from concession agreements The Company operates public utility service concession agreements for water supply and sewage services mostly based on agreements that set out rights and obligations relative to the exploration of assets related to the public utility service (See Note 3.9 (a)). The agreements provide for the return of the assets to the concession grantor at the end of the concession period. As of December 31, 2021 and 2020, the Company operated in 375 372 The services provided by the Company are billed at a price regulated and controlled by São Paulo State Sanitation and Energy Regulatory Agency (ARSESP). Intangible rights arising from concession agreements include: (i) Concession agreements – equity value These refer to municipalities assumed until 2006, except for the municipalities assumed by economic value through assets valuation report prepared by independent experts. The amortization of assets is calculated according to the straight-line method, which considers the assets useful life. (ii) Concession agreements – economic value From 1999 through 2006, the negotiations for new concessions were conducted on the basis of the economic and financial result of the transaction, determined in a valuation report issued by independent appraisers. The amount determined in the related contract, after the transaction is closed with the municipal authorities, realized through the subscription of the Company's shares or in cash, is recorded as "concession agreements" and amortized over the period of the related concession (usually 30 years). As of December 31, 2021 and 2020 there were no amounts pending related to these payments to the municipalities. Intangible assets are amortized on a straight-line basis over the period of the concession agreements or for the useful lives of the underlying assets, whichever is shorter. (iii) Program contracts These refer to the renewal of contracts previously referred to as concession agreements whose purpose is to provide sanitation services. The amortization of the assets acquired until the dates of signatures of the program contracts is calculated according to the straight-line method, which considers the assets’ useful lives. Assets acquired or built after the signature dates of program contracts are amortized during the contracted period (mostly, 30 years) or during the useful lives of underlying assets, whichever is shorter. (iv) Program contracts - Commitments After the enactment of the regulatory framework in 2007, renewals of concessions started to be made through of program contracts. In some of these program contracts, the Company undertook the commitment to financially participate in social and environmental actions. The assets built within the program contracts are recorded as intangible assets and are amortized by the straight-line method in accordance with the duration of the program contract (mostly, 30 years). As of December 31, 2021 and 2020, the amounts not yet disbursed were recorded under “program contract commitments”, in current liabilities, totaling R$ 77,652 162,541 44,995 68,939 (v) Services agreement with the Municipality of São Paulo On June 23, 2010, the Company entered into an agreement with the State of São Paulo and the Municipality of São Paulo to regulate the provision of water and sewage services in the municipality of São Paulo for a 30-year period, which is extendable for an another 30-year period. Also on June 23, 2010, an agreement was signed between the state and municipal government, and SABESP and the Sanitation and Energy Regulatory Agency of the State of São Paulo (“ARSESP”) are the consenting and intervening parties, whose main aspects are the following: 1. The State and the Municipality of São Paulo grant to SABESP the right to explore the sanitation services in the capital of the State of São Paulo, which consists of the obligation to provide such service and charge the respective tariff for this service; 2. The State and the Municipality sets forth ARSESP as the agency responsible for regulating the tariff, controlling and monitoring the services. 3. The evaluation model of the contract was the discounted cash flow, which considered the financial and economic sustainability of SABESP’s operations in the metropolitan region of São Paulo; 4. All operating costs, taxes, investments and the opportunity cost of investors and the creditors of SABESP’s were considered in the cash flow analysis; 5. The agreement provides for investments established in the agreement comply with the minimum of 13% of the gross revenue from the municipality of São Paulo, net of the taxes on revenues. Investment plans referring to SABESP’s execution shall be compatible with the activities and programs foreseen in the state, municipal sanitation plans, and where applicable, the metropolitan plan. The investment plan is not definite and will be revised by Managing Committee every four years, especially as to investments to be made in the following period; 6. The payment related to the Municipal Fund of Environmental Sanitation and Infrastructure to be applied in the sanitation service within the municipality must be recovered through the tariffs charges. Such payment represents 7.5 7. The opportunity cost of the investors and the creditors was established by the Weighted Average Cost of Capital (WACC) methodology. The WACC was the interest rate used to discount the cash flow of the operation; and 8. The agreement considers the recovery of net assets in operation, preferably evaluated through equity valuation or carrying amount monetarily restated, as defined by ARSESP. In addition, the agreement provides for the remuneration of investments to be made by SABESP, so that there is no residual value at the end of the agreement. Referring to the recovery through tariff, mentioned in item 6 above, of transfer to the Municipal Fund of Environmental Sanitation and Infrastructure, ARSESP issued in April 2013, the Resolution no. 413, postponing the application of Resolution no. 407 until the conclusion of the tariff revision process, the transfer to the bill of services of amounts referring to the municipal charges which were stipulated in Resolution no. 407. The postponement to apply Resolution no. 407 was due to a request by the São Paulo State Government to analyze, among other things, methods to reduce the impact on consumers. As of April 18, 2014, ARSESP Resolution no. 484 was published with the final results of SABESP’s Tariff Revision, however, both the São Paulo Municipal Government, through Official Letter no. 1,309/2014-SGM/GAB and the São Paulo State Government through a petition filed by the São Paulo State Office, through the Official Letter ATG/Official Letter no. 092/2014-CC, requested a postponement of the effects of ARSESP Resolution no. 413, published in the São Paulo State Official Gazette on March 20, 2013, until the conclusion of the revision of the Agreement entered into between the São Paulo Municipal Government, the São Paulo State and SABESP. On May 9, 2018, ARSESP announced the final result of the Second Ordinary Tariff Revision and, as of this revision cycle, ARSESP has been passing-on on the tariffs up to 4% of municipal revenue, which is transferred from SABESP to the Municipal Fund for Environmental Sanitation and Infrastructure legally created. Under the Second Ordinary Tariff Revision, concluded in May 2018, the only contract providing for that transfer and meeting the requirements of ARSESP was the one executed with the municipality of São Paulo. Accordingly, 4% of the funds transferred to the Municipal Fund for Environmental Sanitation and Infrastructure of São Paulo were passed-on to the tariffs of the tariff cycle ended in April 2021. The Municipal Government of São Paulo and the Company have not reached an agreement to define the percentage of the Municipal Fund for Environmental Sanitation and Infrastructure transfer to the tariffs charged by the Company in the Municipality of São Paulo, which led to the filing by the municipality claiming the percentage provided for in the contract between the parties. The municipality required the suspension of the lawsuit and SABESP has not yet been summoned. At the time of execution of the agreement, the municipality of São Paulo and the Company did not conclude an agreement to settle the pending financial issues existing, related to the rendering water supply and sewage services to the properties of the Municipality, and for that reason, the Company filed lawsuits for collection of the aforementioned amounts, which remain in progress and are recorded under allowance for doubtful accounts. The agreement represents 44.45 44.58 (d) Public-Private Partnership - PPP SABESP carries out operations related to the PPPs mentioned below. These operations and their respective obligations and guarantees are supported by agreements executed according to Law 11,079/2004. Alto Tietê Production System The Company and the special purpose entity CAB-Sistema Produtor Alto Tietê S/A (currently SPAT Saneamento S/A), formed by Galvão Engenharia S.A. and Companhia Águas do Brasil – Cab Ambiental, signed in June 2008 the contract of Public-Private Partnership of Alto Tietê production system. The service contract is valid for 15 years and has the purpose of expanding the capacity of the Taiaçupeba Water Treatment Station, from 10 thousand to 15 thousand of liters per second. The operation started in October 2011. As of December 31, 2021 and 2020, the carrying amounts related to this PPP recorded in intangible assets were R$ 269,062 287,645 SABESP monthly transfers funds from tariffs collected for services provided to the SPE CAB Sistema Produtor Alto Tietê S/A , in the amount of R$ 13,265 The guarantee has been effective since the beginning of the operation and will be valid until the end, termination, intervention, annulment or caducity of the Administrative Concession, or other events of extinction provided for in the Concession Agreement or in the legislation applicable to administrative concessions, including in the event of bankruptcy or dissolution of the SPE. São Lourenço Production System In August 2013, the Company and the special purpose entity Sistema Produtor São Lourenço S/A, formed by of Construções e Comércio Camargo Corrêa S/A and Construtora Andrade Gutierrez S/A, signed the Public-Private Partnership agreements of the São Lourenço Production System. In May 2018, the control of SPE Sistema Produtor São Lourenço S/A was transferred to CGGC Construtora do Brasil Ltda, previously formed of Construções e Comércio Camargo Corrêa S/A and Construtora Andrade Gutierrez S/A. The objective of the contract is: a) the construction of a water production system, mainly consisting of a water pipeline connecting Ibiúna to Barueri, a water collection station in Ibiúna, a water treatment station in Vargem Grande Paulista and water reservoirs; and b) the provision of services for a 25-year term, aiming at rendering services to operate the dehydration system, drying and final disposal of sludge, maintenance and works of the São Lourenço Production System. The works started in April 2014 and The São Lourenço Production System (SPSL) PPP started operating on July 10, 2018. Since the beginning of operations, the Company monthly transfers funds from tariffs collected for services provided to the SPE Sistema Produtor São Lourenço S/A, in the amount of R$ 36,519 The guarantee will become effective as of the beginning of the system’s appropriate operation, duly accepted by SABESP, valid until the occurrence of any of the following events, whichever occurs first: (i) the original payment date of the last installment of interest / amortization of the principal taken out by the SPE to execute the works; (ii) the end, termination, intervention, annulment, caducity of the Administrative Concession, or other extinction events provided for in the Concession Agreement or in the law applicable to administrative concessions, including bankruptcy or extinction of the SPE. As of December 31, 2021 and 2020, the carrying amounts recorded in the Company’s intangible assets, related to this PPP, amounted to R$ 2,895,798 3,065,445 7.80 The obligations assumed by the Company as of December 31, 2021 and 2020 are shown in the table below: December 31, 2021 December 31, 2020 Current liabilities Noncurrent liabilities Total liabilities Current liabilities Noncurrent liabilities Total liabilities Alto Tietê 69,442 102,873 172,315 59,429 149,726 209,155 São Lourenço 73,315 2,814,555 2,887,870 70,778 2,895,340 2,966,118 Total 142,757 2,917,428 3,060,185 130,207 3,045,066 3,175,273
The obligations assumed by the Company as of December 31, 2021 and 2020 are shown in the table below:	The obligations assumed by the Company as of December 31, 2021 and 2020 are shown in the table below: December 31, 2021 December 31, 2020 Current liabilities Noncurrent liabilities Total liabilities Current liabilities Noncurrent liabilities Total liabilities Alto Tietê 69,442 102,873 172,315 59,429 149,726 209,155 São Lourenço 73,315 2,814,555 2,887,870 70,778 2,895,340 2,966,118 Total 142,757 2,917,428 3,060,185 130,207 3,045,066 3,175,273
Right of use	(g) Right of use Nature December 31, 2021 December 31, 2020 Leases - Contract Assets 276,893 276,893 Leases - Concession Agreements and Program Contracts Cost 405,446 405,426 Accumulated amortization (159,765) (135,865) (=) Net 245,681 269,561 Other assets (*) Vehicles 142,003 115,208 Properties 6,570 15,508 Equipment 9,841 4,541 Other assets 15,301 6,525 Accumulated amortization (69,862) (99,106) (=) Net 103,853 42,676 Right of use 626,427 589,130
The table below shows the impact in the income statements:	The table below shows the impact in the income statements: Impact in the income statement December 31, 2021 December 31, 2020 December 31, 2019 Right-of-use amortization (75,041) (79,834) (65,413) Financial result – interest expenses (68,730) (62,956) (54,791) Short-term and low-value lease expenses (22,467) (13,845) (51,855) Decrease of the income of the year (166,238) (156,635) (172,059)

Property, plant and equipment (

Property, plant and equipment (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of statement of financial position details	Schedule of statement of financial position details December 31, 2021 December 31, 2020 Cost Accumulated depreciation Net Annual Depreciation average rate Cost Accumulated depreciation Net Annual Depreciation average rate Land 94,213 — 94,213 — 94,213 — 94,213 — Buildings 86,703 (41,205) 45,498 2.1 86,860 (41,513) 45,347 2.1 Equipment 397,782 (282,628) 115,154 15.1 372,103 (271,087) 101,016 14.8 Transportation equipment 10,434 (7,962) 2,472 9.9 10,319 (7,350) 2,969 9.9 Furniture and fixtures 36,561 (14,482) 22,079 6.7 31,232 (13,813) 17,419 6.7 Other 11,982 (241) 11,741 5.0 7,618 (331) 7,287 4.9 Total 637,675 (346,518) 291,157 11.1 602,345 (334,094) 268,251 11.2
Schedule of changes in property, plant, and equipment	Schedule of changes in property, plant, and equipment December 31, 2020 Additions Transfers Write-offs and disposals Depreciation December 31, 2021 Land 94,213 — — — — 94,213 Buildings 45,347 3,181 (1,965) (5) (1,060) 45,498 Equipment 101,016 38,807 (3,398) (365) (20,906) 115,154 Transportation equipment 2,969 97 69 — (663) 2,472 Furniture and fixtures 17,419 4,477 1,647 (206) (1,258) 22,079 Other 7,287 3,719 865 — (130) 11,741 Total 268,251 50,281 (2,782) (576) (24,017) 291,157 December 31, 2019 Additions Transfers Write-offs and disposals Depreciation December 31, 2020 Land 92,962 — 1,251 — — 94,213 Buildings 41,705 5,430 (713) — (1,075) 45,347 Equipment 152,273 26,055 (49,188) (174) (27,950) 101,016 Transportation equipment 1,984 298 1,351 — (664) 2,969 Furniture and fixtures 18,219 4,087 (3,712) (103) (1,072) 17,419 Other 7,250 6,537 (6,446) — (54) 7,287 Total 314,393 42,407 (57,457) (277) (30,815) 268,251 December 31, 2018 Additions Transfers Write-offs and disposals Depreciation December 31, 2019 Land 92,979 — (17) — — 92,962 Buildings 40,125 3,497 15 — (1,932) 41,705 Equipment 116,086 63,216 3,149 (429) (29,749) 152,273 Transportation equipment 3,473 308 (1,117) (2) (678) 1,984 Furniture and fixtures 13,578 5,266 734 (162) (1,197) 18,219 Other 1,371 5,872 66 — (59) 7,250 Total 267,612 78,159 2,830 (593) (33,615) 314,393

Borrowings and financing (Table

Borrowings and financing (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of borrowings and financing outstanding	Schedule of borrowings and financing outstanding Borrowings and financing outstanding balance December 31, 2021 December 31, 2020 Financial institution Current Noncurrent Total Current Noncurrent Total Local currency 12th issue debentures 45,450 113,049 158,499 45,450 158,425 203,875 14th issue debentures 25,388 — 25,388 51,873 24,205 76,078 17th issue debentures 102,252 101,982 204,234 91,850 183,335 275,185 18th issue debentures 48,479 92,677 141,156 45,918 135,105 181,023 21st issue debentures 174,849 — 174,849 175,000 174,769 349,769 22nd issue debentures 200,000 508,530 708,530 99,969 678,149 778,118 23rd issue debentures — 864,776 864,776 — 864,678 864,678 24th issue debentures — 461,350 461,350 — 414,994 414,994 25th issue debentures — — — 1,442,610 — 1,442,610 26th issue debentures — 1,168,317 1,168,317 — 1,047,767 1,047,767 27th issue debentures — 997,433 997,433 — 997,000 997,000 28th issue debentures — 1,197,395 1,197,395 — — — 29th issue debentures — 1,230,602 1,230,602 — — — Brazilian Federal Savings Bank 98,784 1,380,170 1,478,954 90,382 1,324,459 1,414,841 Brazilian Development Bank - BNDES PAC 13,394 6,665 20,059 13,185 20,247 33,432 Brazilian Development Bank - BNDES PAC II 9751 7,161 30,308 37,469 7,159 37,447 44,606 Brazilian Development Bank - BNDES PAC II 9752 4,851 20,619 25,470 4,851 25,470 30,321 Brazilian Development Bank - BNDES ONDA LIMPA 26,751 60,089 86,840 26,751 86,809 113,560 Brazilian Development Bank - BNDES TIETÊ III 117,593 617,251 734,844 86,823 542,519 629,342 Brazilian Development Bank - BNDES 2015 33,558 420,685 454,243 33,558 454,126 487,684 Brazilian Development Bank - BNDES 2014 6,524 22,874 29,398 5,143 23,017 28,160 Inter-American Development Bank - BID 2202 181,349 2,344,403 2,525,752 181,349 2,524,798 2,706,147 Inter-American Development Bank - BID INVEST 34,800 890,400 925,200 44,815 898,060 942,875 Leases (Concession Agreements, Program Contracts and Contract Assets) 36,640 360,671 397,311 28,847 399,896 428,743 Leases (Others) 69,306 56,663 125,969 36,576 9,300 45,876 Other 4,790 9,274 14,064 3,778 11,382 15,160 Interest and charges 239,581 — 239,581 158,918 — 158,918 Total in local currency 1,471,500 12,956,183 14,427,683 2,674,805 11,035,957 13,710,762 Borrowings and financing outstanding balance December 31, 2021 December 31, 2020 Financial institution Current Noncurrent Total Current Noncurrent Total Foreign currency Inter-American Development Bank - BID 1212 – US$41,112 thousand (US$51,390 thousand in December 2020) 57,357 172,071 229,428 53,412 213,649 267,061 Inter-American Development Bank - BID 4623 – US$30,329 thousand (US$ 10.220 thousand in December 2020) — 155,192 155,192 — 46,474 46,474 International Bank of Reconstruction and Development -BIRDs 7662 e 8906 – US$76,712 thousand (US$82,792 thousand in December 2020) 33,927 386,328 420,255 31,594 393,949 425,543 JICA 15 – ¥9,219,440 thousand (¥10,371,870 thousand in December 2020) 55,858 391,008 446,866 58,117 464,936 523,053 JICA 18 – ¥8,289,280 thousand (¥9,325,440 thousand in December 2020) 50,223 351,398 401,621 52,253 417,846 470,099 JICA 17 – ¥3,706,564 thousand (¥3,349,203 thousand in December 2020) 12,833 165,900 178,733 11,260 156,738 167,998 JICA 19 – ¥28,109,529 thousand (¥29,923,047 thousand in December 2020) 87,901 1,272,803 1,360,704 91,456 1,415,683 1,507,139 BID 1983AB – US$15,385 thousand (US$23,077 thousand in December 2020) 42,927 42,336 85,263 39,975 78,943 118,918 Interest and charges 18,091 — 18,091 21,577 — 21,577 Total in foreign currency 359,117 2,937,036 3,296,153 359,644 3,188,218 3,547,862 Total borrowings and financing 1,830,617 15,893,219 17,723,836 3,034,449 14,224,175 17,258,624
Schedule of borrowings terms	Schedule of borrowings terms Local currency Guarantees Maturity Annual interest rates Inflation adjustment 12th issue debentures Own funds 2025 TR + 9.5% 14th issue debentures Own funds 2022 TJLP +1.92% (Series 1 and 3) and 9.19% (Series 2) IPCA (Series 2) 17th issue debentures Own funds 2023 CDI +0.75% (Series 1) and 4.5% (Series 2) and 4.75% (Series 3) IPCA (Series 2 and 3) 18th issue debentures Own funds 2024 TJLP + 1.92 % (Series 1 and 3) and 8.25% (Series 2) IPCA (Series 2) 21st issue debentures Own funds 2022 CDI + 0.60% e CDI+ 0.90% 22nd issue debentures Own funds 2025 CDI +0.58% (Series 1) and CDI + 0.90% (Series 2) and 6.0% (Series 3) IPCA (Series 3) 23rd issue debentures Own funds 2027 CDI +0.49% (Series 1) and CDI + 0.63% (Series 2) 24th issue debentures Own funds 2029 3.20% (Series 1) and 3.37% (Series 2) IPCA (Series 1 and 2) 25th issue debentures Own funds 2021 CDI + 3.3% 26th issue debentures Own funds 2030 4.65% (series 1) and 4.95% (series 2) IPCA (series 1 and 2) 27th issue debentures Own funds 2027 CDI +1.60% (Series 1) and CDI + 1.80% (Series 2) and 2.25% (Series 3) 28th issue debentures Own funds 2028 CDI +1.20% (Series 1) and CDI + 1.44% (Series 2) and 1.60% (Series 3) 29th issue debentures Own funds 2036 CDI +1.29% (Series 1) and 5.3058% (Series 2) and 5.4478% (Series 3) IPCA (series 2 and 3) Brazilian Federal Savings Bank Own funds 2021/2042 5% to 9.5% TR Brazilian Development Bank - BNDES PAC Own funds 2023 TJLP+1.82% Brazilian Development Bank - BNDES PAC II 9751 Own funds 2027 TJLP+1.72% Brazilian Development Bank - BNDES PAC II 9752 Own funds 2027 TJLP+1.72% Brazilian Development Bank - BNDES ONDA LIMPA Own funds 2025 TJLP+1.92% Brazilian Development Bank - BNDES TIETÊ III Own funds 2028 TJLP+1.66% Brazilian Development Bank - BNDES 2015 Own funds 2035 TJLP+2.18% Brazilian Development Bank - BNDES 2014 Own funds 2026 TJLP+1.76% Inter-American Development Bank – BID 2202 Government 2035 CDI+0.86% Inter-American Development Bank – BID INVEST Own funds 2034 CDI+1.90% and CDI+2.70% Leases (Concession Agreements, Program Contracts and Contract Assets) 2035 7.73% to 10.12% IPC Leases (Others) 2023 4.25% to 12.34% Other Own funds 2025 3% (FEHIDRO) and TJLP + 1.5% (FINEP) Foreign currency Guarantees Maturity Annual interest rates Exchange rate changes Inter-American Development Bank - BID 1212 - US$41,112 thousand Government 2025 3.31% (*) US$ Inter-American Development Bank - BID 4623 - US$30,329 thousand Government 2044 1.12% (*) US$ International Bank for Reconstruction and Development – BIRDs 7662 and 8906 - US$76,712 thousand Government 2034 2.85% (*) US$ JICA 15 – ¥9,219,440 thousand Government 2029 1.8% and 2.5% Yen JICA 18 – ¥8,289,280 thousand Government 2029 1.8% and 2.5% Yen JICA 17– ¥3,706,564 thousand Government 2035 1.2% and 0.01% Yen JICA 19– ¥28,109,529 thousand Government 2037 1.7% and 0.01% Yen BID 1983AB – US$15,385 thousand - 2023 2.08% to 2.38% (*) US$ (*) Rates comprising LIBOR + contractually defined spread.
Schedule of borrowings payment schedule	(i) Payment schedule – book value as of December 31, 2021 Schedule of borrowings payment schedule 2022 2023 2024 2025 2026 2027 2028 to 2044 TOTAL LOCAL CURRENCY Debentures 596,418 694,806 1,062,558 1,194,424 1,074,178 1,153,648 1,556,497 7,332,529 Brazilian Federal Savings Bank 98,784 94,055 93,315 99,152 105,355 111,936 876,357 1,478,954 BNDES 209,832 203,103 196,438 176,274 166,466 154,029 282,181 1,388,323 BID 2202 181,349 181,349 181,349 181,349 181,349 181,349 1,437,658 2,525,752 BID INVEST 34,800 37,340 39,550 44,300 106,390 108,728 554,092 925,200 Leases (Concession Agreements, Program Contracts and Contract Assets) 36,640 39,132 40,228 44,322 30,846 30,481 175,662 397,311 Leases (Others) 69,306 40,094 9,640 5,656 1,273 — — 125,969 Other 4,790 4,719 2,393 2,162 — — — 14,064 Interest and charges 239,581 — — — — — — 239,581 TOTAL IN LOCAL CURRENCY 1,471,500 1,294,598 1,625,471 1,747,639 1,665,857 1,740,171 4,882,447 14,427,683 FOREIGN CURRENCY BID 57,357 57,357 57,357 61,811 8,908 8,908 132,922 384,620 BIRD 33,927 33,928 33,928 33,928 33,928 33,928 216,688 420,255 JICA 206,815 206,815 206,815 206,815 206,815 206,815 1,147,034 2,387,924 BID 1983AB 42,927 42,336 — — — — — 85,263 Interest and charges 18,091 — — — — — — 18,091 TOTAL IN FOREIGN CURRENCY 359,117 340,436 298,100 302,554 249,651 249,651 1,496,644 3,296,153 Overall Total 1,830,617 1,635,034 1,923,571 2,050,193 1,915,508 1,989,822 6,379,091 17,723,836
Schedule of changes in borrowings	Schedule of changes in borrowings December 31, 2020 Addition (lease) Funding Borrowing costs Monetary and exchange variation Inflation adjustment / exchange variation and incorporated interest – Capitalized Interest paid Amortization Accrued interest Provision for interest and fees – Capitalized Expenses with borrowing costs December 31, 2021 LOCAL CURRENCY Debentures 6,756,504 — 2,450,000 (25,717) 225,106 — (387,618) (1,963,282) 258,114 139,563 15,298 7,467,968 Brazilian Federal Savings Bank 1,418,832 — 156,488 — 685 — (113,030) (93,064) 79,966 33,236 — 1,483,113 BNDES 1,370,902 — 207,136 — — — (88,084) (186,179) 51,122 37,688 259 1,392,844 BID 2202 2,730,195 — — — — — (97,829) (181,349) 63,964 73,506 955 2,589,442 BID INVEST 944,513 — — — — — (33,276) (18,340) 63,380 — 665 956,942 Leases (Concession Agreements, Program Contracts and Contract Assets) 428,743 — — — — — (52,250) (31,432) 52,250 — — 397,311 Leases (Others) 45,876 140,187 — — — — (15,782) (76,013) 31,701 — — 125,969 Other 15,197 — 2,921 (32) — — (718) (3,986) 690 22 — 14,094 TOTAL IN LOCAL CURRENCY 13,710,762 140,187 2,816,545 (25,749) 225,791 — (788,587) (2,553,645) 601,187 284,015 17,177 14,427,683 FOREIGN CURRENCY BIDs 317,302 — 108,728 (7,620) 22,979 — (8,488) (53,197) 7,936 — 197 387,837 BIRD 426,860 — — (3,377) 30,814 — (2,481) (32,965) 1,789 — 241 420,881 Eurobonds 2,684,321 — 34,360 (76) (108,851) 10,198 (43,184) (216,190) 35,315 5,802 192 2,401,887 JICA 119,379 — — — 6,536 — (2,705) (40,607) 1,753 777 415 85,548 BID 1983AB 3,547,862 — 143,088 (11,073) (48,522) 10,198 (56,858) (342,959) 46,793 6,579 1,045 3,296,153 TOTAL IN FOREIGN CURRENCY 17,258,624 140,187 2,959,633 (36,822) 177,269 10,198 (845,445) (2,896,604) 647,980 290,594 18,222 17,723,836 December 31, 2019 Foreign/local currency translation Addition (lease) Funding Borrowing costs Monetary and exchange variation Inflation adjustment / exchange variation and incorporated interest – Capitalized Interest paid Amortization Accrued interest Provision for interest and fees – Capitalized Expenses with borrowing costs December 31, 2020 LOCAL CURRENCY Debentures 3,711,228 — — 3,507,640 (52,328) 86,939 — (161,494) (572,871) 201,150 26,073 10,167 6,756,504 Brazilian Federal Savings Bank 1,429,250 — — 74,485 — — — (111,601) (84,821) 73,067 38,452 — 1,418,832 BNDES 1,201,411 — — 213,514 — — — (47,164) (81,213) 47,668 36,427 259 1,370,902 BID 2202 — 2,807,371 — — — — — (37,613) (90,674) 22,668 27,886 557 2,730,195 BID INVEST — — — 950,000 (7,125) — — — — 1,638 — — 944,513 Leases (Concession Agreements, Program Contracts and Contract Assets) 459,671 — — — — — — (51,431) (30,928) 51,431 — — 428,743 Leases (Others) 74,453 — 28,549 — — — — (9,108) (56,571) 8,553 — — 45,876 Other 9,898 — — 7,250 — — — (671) (1,962) 651 31 — 15,197 TOTAL IN LOCAL CURRENCY 6,885,911 2,807,371 28,549 4,752,889 (59,453) 86,939 — (419,082) (919,040) 406,826 128,869 10,983 13,710,762 FOREIGN CURRENCY BIDs 2,316,190 (2,807,371) — 52,141 (6,635) 845,246 48,246 (45,010) (121,088) 10,490 24,695 398 317,302 BIRD 357,880 — — — (2,029) 102,029 1,217 (7,572) (31,216) 5,659 752 140 426,860 Eurobonds 1,413,956 — — — — 457,931 — (104,170) (1,868,676) 90,941 9,195 823 — JICA 2,106,908 — — 40,830 (117) 715,956 17,841 (43,758) (200,597) 40,172 6,897 189 2,684,321 BID 1983AB 163,864 — — — (152) 59,078 — (7,033) (103,482) 5,843 618 643 119,379 TOTAL IN FOREIGN CURRENCY 6,358,798 (2,807,371) — 92,971 (8,933) 2,180,240 67,304 (207,543) (2,325,059) 153,105 42,157 2,193 3,547,862 TOTAL 13,244,709 — 28,549 4,845,860 (68,386) 2,267,179 67,304 (626,625) (3,244,099) 559,931 171,026 13,176 17,258,624 December 31, 2018 Addition as per IFRS 16 Funding Borrowing costs Monetary variation and exchange rate changes Inflation adjustment / exchange rate changes - Capitalized Interest paid Amortization Accrued interest Provision for interest and fees - Capitalized Amortization of borrowing costs December 31, 2019 LOCAL CURRENCY Debentures 3,486,861 — 1,266,755 (11,814) 42,692 — (234,307) (1,055,623) 195,586 17,233 3,845 3,711,228 Brazilian Federal Savings Bank 1,345,684 — 162,767 — — — (109,128) (79,404) 74,421 34,910 — 1,429,250 BNDES 1,072,605 — 256,981 (628) 2,082 826 (83,419) (131,026) 60,644 23,112 234 1,201,411 Leases (Concession Agreements, Program Contracts and Contract Assets) 568,666 — — — 1,765 3,761 (47,663) (123,880) 49,160 7,862 — 459,671 Leases (Others) (*) — 113,233 — — — — (1,141) (42,646) 5,007 — — 74,453 Other 9,571 — 1,683 — 28 — (655) (1,383) 652 2 — 9,898 TOTAL IN LOCAL CURRENCY 6,483,387 113,233 1,688,186 (12,442) 46,567 4,587 (476,313) (1,433,962) 385,470 83,119 4,079 6,885,911 FOREIGN CURRENCY BID 2,399,985 — — — 40,594 49,387 (83,602) (171,892) 26,332 54,431 955 2,316,190 BIRD 356,420 — 2,540 (2,540) 12,575 1,657 (10,627) (12,273) 8,548 1,561 19 357,880 Deutsche Bank 292,872 — — — 13,255 — (18,562) (303,866) 12,929 1,240 2,132 — Eurobonds 1,358,412 — — — 54,565 — (102,883) — 94,095 8,943 824 1,413,956 JICA 2,036,128 — 117,861 (112) 104,027 3,675 (35,001) (155,064) 32,194 3,013 187 2,106,908 BID 1983AB 225,592 — — (105) 8,943 — (10,338) (71,141) 9,111 870 932 163,864 TOTAL IN FOREIGN CURRENCY 6,669,409 — 120,401 (2,757) 233,959 54,719 (261,013) (714,236) 183,209 70,058 5,049 6,358,798 Overall Total 13,152,796 113,233 1,808,587 (15,199) 280,526 59,306 (737,326) (2,148,198) 568,679 153,177 9,128 13,244,709 (*) The amount presented in Funding for Leasing (IFRS 16) includes R$ 64,955 referring to the initial adoption of the standard on January 1, 2019.
Schedule of funding	The 28th issue debentures was as follows: Schedule of funding Value Maturity Remuneration Series 1 R$ 127,800 07/2024 CDI + 1.20 p.a. Series 2 R$ 888,200 07/2026 CDI + 1.44 p.a. Series 3 R$ 184,000 07/2028 CDI + 1.60 p.a. 29th issue debentures On December 2021, the Company raised the amount of R$1.25 billion referring to the 29th issue of simple and unsecured type debentures, non-convertible into shares, in up three series, according to CVM Instruction 400. The funds raised of the first series will be used to refinance commitments maturing and to recompose the Company's cash. The funds raised of the second and the third series will be used for investment, related to the execution of the projects: (i) Expansion of the Water Supply and Sanitary Sewage Systems in the Metropolitan Region of São Paulo (RMSP) and (ii) Expansion of the Sanitary Sewage System in Baixada Santista. The 29th issue debentures was as follows: Value Maturity Remuneration Series 1 R$ 500,000 12/2026 CDI + 1.29% p.a. Series 2 R$ 600,000 12/2031 IPCA + 5.3058% p.a. Series 3 R$ 150,000 12/2036 IPCA + 5.4478% p.a.
Schedule of restrictive covenants ratios	The table below shows the more restrictive covenants ratios as of December 31, 2021. Schedule of restrictive covenants ratios Covenants Adjusted EBITDA / Adjusted Financial Expenses Equal to or higher than 2.80 EBITDA / Financial Expenses Paid Equal to or higher than 2.35 Adjusted Net Debt / Adjusted EBITDA Equal to or lower than 3.80 Net Debt / Adjusted EBITDA Equal to or lower than 3.50 Total Adjusted Debt / Adjusted EBITDA Lower than 3.65 Other Onerous Debt (1) Equal to or lower than 1.30 Adjusted Current Ratio Higher than 1.00 (1) The contractual definition of “Other Onerous Debts” corresponds to the sum of pension plan obligations and healthcare plan, installment payments of tax debts, and installments payments of debts with the electricity supplier.
Schedule of borrowings and financing - Credit Limits	As of December 31, 2021 and 2020, the Company met the financial debt covenants as set forth by its borrowing and financing agreements. (d) Borrowings and financing – Credit Limits Schedule of borrowings and financing - Credit Limits Agent December 31, 2021 (in millions of reais (*)) Brazilian Federal Savings Bank 1,353 Brazilian Development Bank – BNDES 455 Japan International Cooperation Agency – JICA 48 Inter-American Development Bank – BID 1,505 International Bank for Reconstruction and Development - IBRD 1,392 Other 16 TOTAL 4,769 (*) Brazilian Central Bank’s exchange sell rate as of December 30, 2021 (US$ 1.00 = R$ 5.5805 0.04847

Taxes recoverable_payable (Tabl

Taxes recoverable/payable (Tables)	12 Months Ended
	Dec. 31, 2021
Current assets	(a) Current assets December 31, 2021 December 31, 2020 Recoverable taxes Income tax and social contribution 259,902 — Withholding income tax (IRRF) on financial investments 13,041 4,391 Other federal taxes 3,161 18,281 Total 276,104 22,672
Current liabilities	(b) Current liabilities December 31, 2021 December 31, 2020 Taxes and contributions payable Income tax and social contribution — 69,041 Cofins and Pasep 111,963 93,601 INSS (social security contribution) 39,902 37,599 IRRF (withholding income tax) 49,468 21,287 Other 55,797 45,291 Total 257,130 266,819

Deferred taxes and contributi_2

Deferred taxes and contributions (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of deferred taxes	Schedule of deferred taxes December 31, 2021 December 31, 2020 Deferred income tax assets Provisions 503,374 436,445 Pension obligations - G1 150,577 154,498 Donations of underlying asset on concession agreements 47,589 50,142 Credit losses 183,963 155,719 Other 127,092 134,932 Total deferred tax assets 1,012,595 931,736 Deferred income tax liabilities Temporary difference on concession of intangible asset (368,235) (388,675) Capitalization of borrowing costs (404,931) (390,211) Profit on supply to government entities (353,262) (356,513) Actuarial gain/loss – G1 Plan (109,271) (48,979) Construction margin (46,079) (48,843) Borrowing costs (14,556) (19,231) Total deferred tax liabilities (1,296,334) (1,252,452) Deferred tax assets (liabilities), net (283,739) (320,716)
Schedule of realization	(b) Realization Schedule of realization December 31, 2021 December 31, 2020 Deferred income tax assets to be realized within 12 months 280,373 263,580 to be realized after one year 732,222 668,156 Total deferred tax asset 1,012,595 931,736 Deferred income tax liabilities to be realized within 12 months (31,777) (31,388) to be realized after one year (1,264,557) (1,221,064) Total deferred tax liabilities (1,296,334) (1,252,452) Deferred tax liability (283,739) (320,716)
Schedule of changes	(c) Changes Schedule of changes Deferred income tax assets December 31, 2020 Net change December 31, 2021 Provisions 436,445 66,929 503,374 Pension obligations - G1 154,498 (3,921) 150,577 Donations of underlying asset on concession agreements 50,142 (2,553) 47,589 Credit losses 155,719 28,244 183,963 Other 134,932 (7,840) 127,092 Total 931,736 80,859 1,012,595 Deferred income tax liabilities Temporary difference on concession of intangible asset (388,675) 20,440 (368,235) Capitalization of borrowing costs (390,211) (14,720) (404,931) Profit on supply to governmental entities (356,513) 3,251 (353,262) Actuarial (gain)/loss – G1 (48,979) (60,292) (109,271) Construction margin (48,843) 2,764 (46,079) Borrowing costs (19,231) 4,675 (14,556) Total (1,252,452) (43,882) (1,296,334) Deferred tax liabilities, net (320,716) 36,977 (283,739) Deferred income tax assets December 31, 2019 Net change December 31, 2020 Provisions 366,673 69,772 436,445 Pension obligations - G1 157,998 (3,500) 154,498 Donations of underlying asset on concession agreements 51,818 (1,676) 50,142 Credit losses 145,622 10,097 155,719 Other 183,147 (48,215) 134,932 Total 905,258 26,478 931,736 Deferred income tax liabilities Temporary difference on concession of intangible asset (408,732) 20,057 (388,675) Capitalization of borrowing costs (409,236) 19,025 (390,211) Profit on supply to governmental entities (372,289) 15,776 (356,513) Actuarial (gain)/loss – G1 (54,222) 5,243 (48,979) Construction margin (83,399) 34,556 (48,843) Borrowing costs (11,376) (7,855) (19,231) Total (1,339,254) 86,802 (1,252,452) Deferred tax liabilities, net (433,996) 113,280 (320,716) Deferred income tax assets December 31, 2018 Net change December 31, 2019 Provisions 337,833 28,840 366,673 Pension obligations - G1 157,044 954 157,998 Donations of underlying asset on concession agreements 54,131 (2,313) 51,818 Credit losses 197,920 (52,298) 145,622 Other 186,887 (3,740) 183,147 Total 933,815 (28,557) 905,258 Deferred income tax liabilities Temporary difference on concession of intangible asset (433,842) 25,110 (408,732) Capitalization of borrowing costs (420,978) 11,742 (409,236) Profit on supply to governmental entities (206,978) (165,311) (372,289) Actuarial (gain)/loss – G1 (36,430) (17,792) (54,222) Construction margin (86,164) 2,765 (83,399) Borrowing costs (10,665) (711) (11,376) Total (1,195,057) (144,197) (1,339,254) Deferred tax assets (liabilities), net (261,242) (172,754) (433,996) December 31, 2021 December 31, 2020 December 31, 2019 Opening balance (320,716) (433,996) (261,242) Net change in the year: - corresponding entry to the income statement 97,269 108,037 (154,962) - corresponding entry to valuation adjustments to equity (Note 21 (b)) (60,292) 5,243 (17,792) Total net change 36,977 113,280 (172,754) Closing balance (283,739) (320,716) (433,996)
Reconciliation of the effective tax rate	(d) Reconciliation of the effective tax rate The amounts recorded as income tax and social contribution expenses in the financial statements are reconciled to the statutory rates, as shown below: December 31, 2021 December 31, 2020 December 31, 2019 Profit before income taxes 3,170,156 1,326,002 4,677,942 Statutory rate 34% 34% 34% Estimated expense at statutory rate (1,077,853) (450,841) (1,590,500) Tax benefit of interest on equity 200,073 126,604 312,339 Permanent differences Provision – Law 4,819/1958 – G0 (i) (22,640) (37,675) (44,426) Donations (16,723) (8,672) (19,888) Other differences 52,856 17,900 32,050 Income tax and social contribution (864,287) (352,684) (1,310,425) Current income tax and social contribution (961,556) (460,721) (1,155,463) Deferred income tax and social contribution 97,269 108,037 (154,962) Effective rate 27% 27% 28% (i) Permanent difference related to the provision for actuarial liability (Note 22 (ii) and (v)).

Provisions (Tables)

Provisions (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of lawsuits and proceedings that resulted in provisions	Schedule of lawsuits and proceedings that resulted in provisions December 31, 2021 December 31, 2020 Provisions Escrow deposits Provisions net of deposits Provisions Escrow deposits Provisions net of deposits Customer claims (i) 168,258 (10,780) 157,478 160,705 (10,553) 150,152 Supplier claims (ii) 477,854 (123) 477,731 410,734 (358) 410,376 Other civil claims (iii) 95,601 (2,523) 93,078 86,083 (2,505) 83,578 Tax claims (iv) 57,509 (2,693) 54,816 59,678 (2,410) 57,268 Labor claims (v) 349,962 (15,864) 334,098 316,880 (15,503) 301,377 Environmental claims (vi) 331,326 (34) 331,292 249,582 (31) 249,551 Total 1,480,510 (32,017) 1,448,493 1,283,662 (31,360) 1,252,302 Current 809,821 — 809,821 760,209 — 760,209 Noncurrent 670,689 (32,017) 638,672 523,453 (31,360) 492,093
Schedule of changes in provisions	(II) Changes Schedule of changes in provisions December 31, 2020 Additional provisions Interest and inflation adjustment Use of the accrual Amounts not used (reversal) December 31, 2021 Customer claims (i) 160,705 32,996 29,685 (30,972) (24,156) 168,258 Supplier claims (ii) 410,734 92,135 90,788 (71,238) (44,565) 477,854 Other civil claims (iii) 86,083 15,477 12,850 (10,056) (8,753) 95,601 Tax claims (iv) 59,678 8,630 8,054 (15,133) (3,720) 57,509 Labor claims (v) 316,880 100,245 36,373 (66,220) (37,316) 349,962 Environmental claims (vi) 249,582 40,477 50,957 (33) (9,657) 331,326 Subtotal 1,283,662 289,960 228,707 (193,652) (128,167) 1,480,510 Escrow deposits (31,360) (39,586) (11,852) 48,805 1,976 (32,017) Total 1,252,302 250,374 216,855 (144,847) (126,191) 1,448,493 December 31, 2019 Additional provisions Interest and inflation adjustment Use of the accrual Amounts not used (reversal) December 31, 2020 Customer claims (i) 253,665 16,465 19,638 (78,640) (50,423) 160,705 Supplier claims (ii) 153,654 149,566 201,259 (68,801) (24,944) 410,734 Other civil claims (iii) 93,910 15,944 11,109 (23,009) (11,871) 86,083 Tax claims (iv) 59,143 4,333 2,737 (1,875) (4,660) 59,678 Labor claims (v) 325,129 61,782 35,541 (61,039) (44,533) 316,880 Environmental claims (vi) 192,950 35,392 27,718 — (6,478) 249,582 Subtotal 1,078,451 283,482 298,002 (233,364) (142,909) 1,283,662 Escrow deposits (42,643) (12,907) (2,225) 18,675 7,740 (31,360) Total 1,035,808 270,575 295,777 (214,689) (135,169) 1,252,302 December 31, 2018 Additional provisions Interest and inflation adjustment Use of the accrual Amounts not used (reversal) December 31, 2019 Customer claims (i) 290,649 57,314 53,929 (99,379) (48,848) 253,665 Supplier claims (ii) 67,985 54,223 102,686 (42,948) (28,292) 153,654 Other civil claims (iii) 98,302 28,888 18,713 (9,766) (42,227) 93,910 Tax claims (iv) 63,335 11,821 2,918 (4,982) (13,949) 59,143 Labor claims (v) 302,935 167,995 61,483 (112,084) (95,200) 325,129 Environmental claims (vi) 170,419 42,198 24,358 (312) (43,713) 192,950 Subtotal 993,625 362,439 264,087 (269,471) (272,229) 1,078,451 Escrow deposits (100,763) (14,051) (11,844) 19,191 64,824 (42,643) Total 892,862 348,388 252,243 (250,280) (207,405) 1,035,808
Lawsuits deemed as contingent liabilities	(b) Lawsuits deemed as contingent liabilities The Company is party to lawsuits and administrative proceedings relating to environmental, tax, civil and labor claims, which are assessed as contingent liabilities in the financial statements, since it either does not expect outflows to be required or the amount of the obligation cannot be reliably measured. Contingent liabilities, net of escrow deposits, are represented as follows: December 31, 2021 December 31, 2020 Customer claims (i) 173,875 110,508 Supplier claims (ii) 1,521,935 1,350,308 Other civil claims (iii) 852,735 758,800 Tax claims (iv) 1,548,781 1,253,636 Labor claims (v) 1,095,841 1,005,648 Environmental claims (vi) 3,201,716 5,981,837 Total 8,394,883 10,460,737

Labor and social obligations (T

Labor and social obligations (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of employees benefits	Schedule of employees benefits December 31, 2021 December 31, 2020 Salaries and payroll charges 58,591 53,107 Provision for vacation 226,127 207,906 Healthcare plan (i) 45,915 45,768 Provision for profit sharing (ii) 88,376 91,209 Consent Decree (TAC) 5,723 8,978 Knowledge Retention Program (PRC) 1,884 3,975 Total 426,616 410,943

Pension plan obligations (Table

Pension plan obligations (Tables)	12 Months Ended
	Dec. 31, 2021
Pension Plan Obligations
Schedule of pension plan benefits	Schedule of pension plan benefits December 31, 2021 December 31, 2020 G1 Plan G0 Plan Total G1 Plan G0 Plan Total Present value of the defined benefit obligations (2,764,027) (2,192,062) (4,956,089) (3,112,980) (2,549,541) (5,662,521) Fair value of the plan’s assets 2,634,427 — 2,634,427 2,793,927 — 2,793,927 Total pension plan liabilities (deficit) (129,600) (2,192,062) (2,321,662) (319,053) (2,549,541) (2,868,594)
Schedule of reconciliation of defined benefit obligations	Schedule of reconciliation of defined benefit obligations December 31, 2021 December 31, 2020 G1 Plan G0 Plan Total G1 Plan G0 Plan Total Plan’s liabilities Defined benefit obligation, beginning of the year (3,112,980) (2,549,541) (5,662,521) (3,067,094) (3,046,255) (6,113,349) Current service cost (32,777) — (32,777) (40,404) — (40,404) Interest costs (205,707) (158,244) (363,951) (208,485) (206,262) (414,747) Actuarial (gains)/losses recorded as other comprehensive income 414,823 330,337 745,160 64,637 521,331 585,968 Benefits paid 172,614 185,386 358,000 138,366 181,645 320,011 Defined benefit obligation, end of the year (2,764,027) (2,192,062) (4,956,089) (3,112,980) (2,549,541) (5,662,521) Plan’s assets Fair value of the plan’s assets, beginning of the year 2,793,927 — 2,793,927 2,752,417 — 2,752,417 Expected return of the plan’s assets 184,687 — 184,687 187,317 — 187,317 Company’s contributions 35,368 — 35,368 36,010 — 36,010 Participant’s contributions 30,551 — 30,551 36,608 — 36,608 Benefits paid (172,614) — (172,614) (138,366) — (138,366) Actuarial gains/(losses) recorded as other comprehensive income (237,492) — (237,492) (80,059) — (80,059) Fair value of the plan’s assets, end of the year 2,634,427 — 2,634,427 2,793,927 — 2,793,927 Total pension plan liabilities (deficit) (129,600) (2,192,062) (2,321,662) (319,053) (2,549,541) (2,868,594)
Schedule of (gains)/losses, due to changes in assumptions	Schedule of (gains)/losses, due to changes in assumptions December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan G0 Plan Total G1 Plan G0 Plan Total G1 Plan G0 Plan Total Actuarial gains/(losses) on obligations 414,823 330,337 745,160 64,637 521,331 585,968 (392,876) (397,597) (790,473) Actuarial gains/(losses) recorded as other comprehensive income (237,492) — (237,492) (80,059) — (80,059) 445,206 — 445,206 Total gains/(losses) 177,331 330,337 507,668 (15,422) 521,331 505,909 52,330 (397,597) (345,267) Deferred income tax and social contribution (60,292) — (60,292) 5,243 — 5,243 (17,792) — (17,792) Equity valuation adjustments 117,039 330,337 447,376 (10,179) 521,331 511,152 34,538 (397,597) (363,059)
Schedule of amounts recognized in income statement	Schedule of amounts recognized in income statement December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan G0 Plan Total G1 Plan G0 Plan Total G1 Plan G0 Plan Total Cost of service, net 2,227 — 2,227 4,608 — 4,608 8,609 227,367 235,976 Interest cost rates 205,707 158,244 363,951 208,485 206,262 414,747 224,429 — 224,429 Expected return on the plan’s assets (184,687) — (184,687) (187,317) — (187,317) (192,965) — (192,965) Amount received from State of São Paulo (undisputed) — (91,657) (91,657) — (95,452) (95,452) — (97,300) (97,300) Total expenses 23,247 66,587 89,834 25,776 110,810 136,586 40,073 130,067 170,140
Obligations’ maturity:	Obligations’ maturity: December 31, 2021 G1 Plan G0 Plan Payment of benefits expected in 2022 198,074 179,875 Payment of benefits expected in 2023 188,437 173,944 Payment of benefits expected in 2024 178,787 167,140 Payment of benefits expected in 2025 169,738 159,604 Payment of benefits expected in 2026 or after 2,028,991 1,511,499 Total 2,764,027 2,192,062 Duration 11.63 years 9.24 years
Actuarial assumptions:	Actuarial assumptions: December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan G0 Plan G1 Plan G0 Plan G1 Plan G0 Plan Discount rate – actual rate (NTN-B) 5.53% p.a. 5.26% p.a. 3.44% p.a. 3.07% p.a. 3.37% p.a. 3.36% p.a. Inflation rate 3.00% p.a. 3.00% p.a. 3.25% p.a. 3.25% p.a. 3.5% p.a. 3.5% p.a. Nominal rate of salary growth 5.06% p.a. 5.06% p.a 5.32% p.a. 5.32% p.a 5.57% p.a. 5.57% p.a Mortality table AT-2000 AT-2000 AT-2000 AT-2000 AT-2000 AT-2000
Sensitivity analysis of the defined benefit pension plan as of December 31, 2021 regarding the changes in the main assumptions are:	Sensitivity analysis of the defined benefit pension plan as of December 31, 2021 regarding the changes in the main assumptions are: Impact on the present value of the defined benefit obligations Assumptions Change in the assumption G1 G0 Discount rate Increase of 1.0% Decrease of R$ 244,999 Decrease of R$ 158,221 Decrease of 1.0% Increase of R$ 289,735 Increase of R$ 180,948 Life expectation Increase of 1 year Increase of R$ 61,361 Increase of R$ 101,021 Decrease of 1 year Decrease of R$ 56,181 Decrease of R$ 90,081 Wage growth rate Increase of 1.0% Increase of R$ 19,402 Increase of R$ 227,529 Decrease of 1.0% Decrease of R$ 16,464 Decrease of R$ 202,363
Estimated expenses for the comig year	Estimated expenses for the comig year 2022 Cost of services, net 1,020 Interest costs 231,745 Net profitability on financial assets (221,079) Expenditures to be recognized by the employer 11,686
Schedule Of Plan’s Assets	The plan’s investment policies and strategies are aim at getting consistent returns and reduce the risks associated to the utilization of financial assets available on the Capital Markets through diversification, considering factors, such as the liquidity needs and the long-term nature of the plan liability, types and availability of financial instruments in the local and international markets, general economic conditions and forecasts as well as requirements under the law. The plan's asset allocation management strategies are determined with the support of reports and analysis prepared by Sabesprev and independent financial advisors: Schedule Of Plan’s Assets December 31, 2021 % December 31, 2020 % Total fixed income 1,613,153 61.2 1,811,164 64.8 Total equities 261,665 9.9 311,958 11.2 Total structured investments 599,970 22.8 575,943 20.6 Other 159,639 6.1 94,862 3.4 Fair value of the plan’s assets 2,634,427 100 2,793,927 100
Estimated expenses for 2022	Estimated expenses for 2022 2022 Interest cost rate 176,953 Expense to be recognized 176,953
Reconciliation of expenses with pension obligations	(v) Reconciliation of expenses with pension obligations December 31, 2021 December 31, 2020 December 31, 2019 G1 Plan 23,247 25,776 40,073 G0 Plan 66,587 110,810 130,067 Sabesprev Mais Plan 22,406 21,700 22,461 VIVEST Plan 160 58 — Subtotal 112,400 158,344 192,601 Expenses capitalized in assets (4,118) (4,904) (6,022) Other 5,527 5,841 8,040 Pension plan obligations (Note 29) 113,809 159,281 194,619

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Share capital	(a) Share capital As of December 31, 2021, and 2020, the authorized, subscribed and paid-in capital, in the amount of R$ 15,000.000 , was composed of 683,509,869 registered, book-entry common shares with no par value, as follows: December 31, 2021 December 31, 2020 Number of shares % Number of shares % State Department of Finance 343,506,664 50.3 343,507,729 50.26 Other shareholders In Brazil (1) 234,965,971 34.4 254,868,646 37.29 Abroad (2) (3) 105,037,234 15.3 85,133,494 12.45 683,509,869 100.0 683,509,869 100.00 (1) As of December 31, 2021, the common shares traded in Brazil were held by 40,428 shareholders. It includes six shares held by Companhia Paulista de Parcerias (CPP), which is controlled by the São Paulo State Government. (2) Shares traded as American Depositary Receipts (ADR) on the New York Stock Exchange, through The Bank New York Mellon, the depositary bank for the Company's ADRs. (3) Each ADR corresponds to 1 share.
Distribution of earnings	(b) Distribution of earnings Shareholders are entitled to a minimum mandatory dividend of 25% of the adjusted net income under Brazilian GAAP, calculated according to the Brazilian corporate law. The dividends do not bear interest and the amounts not claimed within three years from the date of the Shareholders' Meeting that approved them mature in favor of the Company. 2021 2020 2019 Profit for the year 2,305,869 973,318 3,367,517 (-) Legal reserve - 5% 115,293 48,666 168,376 2,190,576 924,652 3,199,141 Minimum mandatory dividend – 25% 547,645 231,163 799,785 Dividend per share and per ADS 0.80122 0.33820 1.17012
Allocation of the profit for the year	(e) Allocation of the profit for the year 2021 2020 2019 Profit (+) Profit for the year 2,305,869 973,318 3,367,517 (-) Legal reserve – 5% 115,293 48,666 168,376 (-) Minimum mandatory dividends 547,645 231,163 799,785 (-) Additional proposed dividends 96,700 40,806 141,203 Investment reserve recorded 1,546,231 652,863 2,258,153
Other comprehensive loss	(g) Other comprehensive loss Gains and losses arising from changes in the actuarial assumptions are accounted for as equity valuation adjustments, net of the effects of income tax and social contribution effects. See Note 22 (b), the breakdown of amounts recorded in 2021 and 2020. G1 plan G0 plan Total Balance as of December 31, 2020 95,075 (496,077) (401,002) Actuarial gains/(losses) for the year (Note 22) 117,039 330,337 447,376 Balance as of December 31, 2021 212,114 (165,740) 46,374

Earnings per share (Tables)

Earnings per share (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of earnings per share, basic and diluted	Basic earnings per share is calculated by dividing the equity attributable to the Company’s owners by the weighted average number of outstanding common shares during the year. The Company does not have potentially dilutive common shares outstanding or debts convertible into common shares. Accordingly, basic and diluted earnings per share are equal. Schedule of earnings per share, basic and diluted 2021 2020 2019 Earnings attributable to Company’s owners 2,305,869 973,318 3,367,517 Weighted average number of common shares issued 683,509,869 683,509,869 683,509,869 Basic and diluted earnings per share (reais per share) 3.37 1.42 4.93

Operating segment information (

Operating segment information (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of operating segment information	Schedule of operating segment information 2021 Sanitation (i) Reconciliation to the financial statements (ii) Balance as per financial statements Gross operating revenue 16,304,206 4,376,739 20,680,945 Gross sales deductions (1,189,884) — (1,189,884) Net operating revenue 15,114,322 4,376,739 19,491,061 Costs, selling, general and administrative expenses (11,115,383) (4,278,337) (15,393,720) Income from operations before other operating expenses, net and equity accounting 3,998,939 98,402 4,097,341 Other operating income / (expenses), net (21,841) Equity accounting 22,079 Financial result, net (927,423) Income from operations before taxes 3,170,156 Depreciation and amortization (2,253,322) — (2,253,322) (i) See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information; (ii) Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (b). Result 2020 Sanitation (i) Reconciliation to the financial statements (ii) Balance as per financial statements Gross operating revenue 15,157,780 3,716,616 18,874,396 Gross sales deductions (1,076,855) — (1,076,855) Net operating revenue 14,080,925 3,716,616 17,797,541 Costs, selling, general and administrative expenses (9,796,821) (3,630,139) (13,426,960) Income from operations before other operating expenses, net and equity accounting 4,284,104 86,477 4,370,581 Other operating income / (expenses), net 107,656 Equity accounting 14,136 Financial result, net (3,166,371) Income from operations before taxes 1,326,002 Depreciation and amortization (2,037,112) — (2,037,112) (i) See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information; (ii) Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (e). Result 2019 Sanitation (i) Reconciliation to the financial statements (ii) Balance as per financial statements Gross operating revenue 16,134,032 2,946,566 19,080,598 Gross sales deductions (1,096,944) — (1,096,944) Net operating revenue 15,037,088 2,946,566 17,983,654 Costs, selling, general and administrative expenses (9,375,590) (2,881,394) (12,256,984) Income from operations before other operating expenses, net and equity accounting 5,661,498 65,172 5,726,670 Other operating income / (expenses), net (18,748) Equity accounting 3,701 Financial result, net (1,033,681) Income from operations before taxes 4,677,942 Depreciation and amortization (1,780,094) (1,780,094) (i) See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information; (ii) Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (b).

Insurance (Tables)

Insurance (Tables)	12 Months Ended
	Dec. 31, 2021
As of December 31, 2021, the Company’s insurance was as follows:	As of December 31, 2021, the Company’s insurance was as follows: Coverage Specified risks – fire 2,185,827 Engineering risk 2,254,238 Guarantee insurance for escrow deposit and traditional guarantee 600,000 * Civil liability– D&O (Directors and Officers) 100,000 Civil liability – works 172,140 Civil liability – operations 10,000 Other 26,900 Total 5,349,105 (*) SABESP has an agreement that allows issuing policies that total such insured amount. Of the total, R$ 98,530 thousand in policies with guarantee insurance were issued.

Operating revenue (Tables)

Operating revenue (Tables)	12 Months Ended
	Dec. 31, 2021
Revenue from sanitation services:	(a) Revenue from sanitation services: 2021 2020 2019 Metropolitan Region of São Paulo 11,529,229 10,722,384 11,849,776 Regional Systems 4,774,977 4,435,396 4,284,256 Total 16,304,206 15,157,780 16,134,032
Reconciliation from gross operating income to net operating income:	(b) Reconciliation from gross operating income to net operating income: 2021 2020 2019 Revenue from sanitation services (i) 16,304,206 15,157,780 16,134,032 Construction revenue 4,376,739 3,716,616 2,946,566 Sales tax (1,121,905) (1,009,358) (1,035,051) Regulatory, Control and Oversight Fee (TRCF) (67,979) (67,497) (61,893) Net revenue 19,491,061 17,797,541 17,983,654 (i) Includes the amount of R$ 80,329 corresponding to the TRCF charged from customers from the municipalities regulated by ARSESP (R$ 72,962 in 2020).

Operating costs and expenses (T

Operating costs and expenses (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of operating costs and expenses	Schedule of operating costs and expenses 2021 2020 2019 Operating costs Salaries, payroll charges and benefits (2,026,202) (1,958,395) (1,938,265) Pension plan obligations (36,771) (37,281) (49,564) Construction costs (Note 26) (4,278,337) (3,630,139) (2,881,394) General supplies (314,111) (244,054) (259,401) Treatment supplies (364,542) (338,756) (310,380) Outsourced services (1,517,196) (1,251,839) (1,250,890) Electricity (1,462,776) (1,214,831) (1,140,160) General expenses (717,352) (622,113) (647,804) Depreciation and amortization (2,082,755) (1,882,259) (1,659,779) (12,800,042) (11,179,667) (10,137,637) Selling expenses Salaries, payroll charges and benefits (265,435) (271,565) (270,549) Pension plan obligations (4,868) (5,059) (6,848) General supplies (7,976) (5,471) (10,332) Outsourced services (343,763) (290,512) (360,190) Electricity (1,340) (1,200) (1,333) General expenses (136,107) (118,278) (122,503) Depreciation and amortization (66,390) (59,201) (31,649) (825,879) (751,286) (803,404) Bad debt expense, net of recoveries (Note 10 (c)) (643,730) (444,826) (128,099) Administrative expenses Salaries, payroll charges and benefits (250,557) (257,829) (278,507) Pension plan obligations (72,170) (116,941) (138,207) General supplies (11,209) (14,237) (3,216) Outsourced services (250,801) (230,054) (197,357) Electricity (1,715) (1,359) (1,436) General expenses (357,564) (257,693) (407,250) Depreciation and amortization (104,177) (95,652) (88,666) Tax expenses (75,876) (77,416) (73,205) (1,124,069) (1,051,181) (1,187,844) Operating costs and expenses Salaries, payroll charges and benefits (2,542,194) (2,487,789) (2,487,321) Pension obligations (113,809) (159,281) (194,619) Construction costs (Note 26) (4,278,337) (3,630,139) (2,881,394) General supplies (333,296) (263,762) (272,949) Treatment supplies (364,542) (338,756) (310,380) Outsourced services (2,111,760) (1,772,405) (1,808,437) Electricity (1,465,831) (1,217,390) (1,142,929) General expenses (1,211,023) (998,084) (1,177,557) Depreciation and amortization (2,253,322) (2,037,112) (1,780,094) Tax expenses (75,876) (77,416) (73,205) Bad debt expense, net of recoveries (Note 10 (c)) (643,730) (444,826) (128,099) (15,393,720) (13,426,960) (12,256,984)

Financial Income (Expenses) (Ta

Financial Income (Expenses) (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of financial income (expenses)	Schedule of financial income (expenses) 2021 2020 2019 Financial expenses Interest and charges on borrowings and financing – local currency (517,235) (348,050) (331,367) Interest and charges on borrowings and financing – foreign currency (46,793) (136,257) (165,421) Other financial expenses (315,013) (328,413) (344,508) Income tax over international remittance — (15,134) (17,650) Inflation adjustment on borrowings and financing (225,791) (86,938) (44,802) Other inflation adjustments (172,632) (142,313) (107,584) Interest and inflation adjustments on provisions (i) (170,831) (267,654) (162,093) Total financial expenses (1,448,295) (1,324,759) (1,173,425) Financial income Inflation adjustment gains 198,907 120,957 91,180 Income on financial investments 150,632 75,522 151,622 Interest income 145,866 162,576 150,054 Cofins and Pasep (23,038) (22,328) (20,028) Other 41 4 14 Total financial income 472,408 336,731 372,842 Financial income (expenses), net before exchange rate changes (975,887) (988,028) (800,583) Exchange gains (losses) Exchange rate changes on borrowings and financing (ii) 48,522 (2,180,241) (233,960) Exchange rate changes on assets (36) 1,894 863 Other exchange rate changes (22) 4 (1) Exchange rate changes, net 48,464 (2,178,343) (233,098) Financial income (expenses), net (927,423) (3,166,371) (1,033,681)

Other operating income (expen_2

Other operating income (expenses), net (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of other operating income (expenses), net	Schedule of other operating income (expenses), net 2021 2020 2019 Other operating income, net 71,877 70,288 75,667 Other operating expenses (93,718) 37,368 (94,415) Other operating income (expenses), net (21,841) 107,656 (18,748)

Commitments (Tables)

Commitments (Tables)	12 Months Ended
	Dec. 31, 2021
Below, the main unrecorded committed amounts as of December 31, 2020:	The Company has agreements to manage and maintain its activities, as well as agreements to build new projects aiming at achieving the objectives proposed in its target plan. Below, the main unrecorded committed amounts as of December 31, 2020: 1 year 1-3 years 3-5 years More than 5 years Total Contractual obligations – Expenses 1,147,112 745,388 187,150 790,650 2,870,300 Contractual obligations – Investments 2,258,647 1,741,424 1,425,790 331,184 5,757,045 Total 3,405,759 2,486,812 1,612,940 1,121,834 8,627,345

Supplemental cash flow inform_2

Supplemental cash flow information (Tables)	12 Months Ended
	Dec. 31, 2021
Supplemental Cash Flow Information
Schedule of supplemental cash flow information	Schedule of supplemental cash flow information 2021 2020 2019 Total additions to contract assets (Note 14) 4,759,789 3,948,158 3,532,283 Total additions to intangible assets (Note 15 (b)) 172,961 411,285 1,788,907 Items not affecting cash (see breakdown below) (1,236,081) (1,095,786) (2,125,943) Total additions to intangible assets as per statement of cash flows 3,696,669 3,299,657 3,195,247 Investments and financing operations affecting intangible assets but not cash: Interest capitalized in the year (Note 14 (a)) 300,792 238,330 233,251 Contractors payable 218,523 142,514 252,675 Program contract commitments — 4,422 35,817 Public Private Partnership - São Lourenço PPP (Note 15 (g)) — — 10,591 Performance agreements 478,177 314,720 78,296 Right of use 140,187 28,549 113,233 Construction margin (Note 26) 98,402 85,976 65,172 Agreement with the Municipality of Mauá — 280,774 — Agreement with the municipality of Santo André — — 1,336,908 Total 1,236,081 1,095,786 2,125,943

The table below shows a summary

The table below shows a summary of the contractual situation of the municipalities served: (Details) R$ in Thousands, Municipalities in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)Municipalities	Dec. 31, 2020BRL (R$)Municipalities
IfrsStatementLineItems [Line Items]
Total municipalities that have already signed contracts | Municipalities		342
Balance – intangible and contract assets		R$ 39440568
Percentage of intangible and contract assets		93.08%
Revenue from sanitation services (excluding construction revenue)		R$ 14406803
Percentage of revenue from sanitation services (excluding construction revenue)		95.05%
Municipalities with expired contracts: | Municipalities		8
Balance – intangible and contract assets		R$ 264931
Percentage of intangible and contract assets		0.63%
Revenue from sanitation services (excluding construction revenue)		R$ 39088
Percentage of revenue from sanitation services (excluding construction revenue)		0.26%
Municipalities with concession agreements due by 2030: | Municipalities		25
Balance – intangible and contract assets		R$ 1436529
Percentage of intangible and contract assets		3.39%
Revenue from sanitation services (excluding construction revenue)		R$ 597483
Percentage of revenue from sanitation services (excluding construction revenue)		3.94%
Municipality of São Paulo:
Percentage of intangible and contract assets		37.94%
Percentage of revenue from sanitation services (excluding construction revenue)		44.58%
Sao Paulo [Member]
IfrsStatementLineItems [Line Items]
Total municipalities that have already signed contracts | Municipalities	342
Balance – intangible and contract assets	R$ 42260091
Percentage of intangible and contract assets	93.80%
Revenue from sanitation services (excluding construction revenue)	R$ 15490808
Percentage of revenue from sanitation services (excluding construction revenue)	95.01%
Municipalities with expired contracts: | Municipalities	8
Balance – intangible and contract assets	R$ 214329
Percentage of intangible and contract assets	0.48%
Revenue from sanitation services (excluding construction revenue)	R$ 41194
Percentage of revenue from sanitation services (excluding construction revenue)	0.25%
Municipalities with concession agreements due by 2030: | Municipalities	25
Balance – intangible and contract assets	R$ 1127920
Percentage of intangible and contract assets	2.50%
Revenue from sanitation services (excluding construction revenue)	R$ 653408
Percentage of revenue from sanitation services (excluding construction revenue)	4.01%
Municipality of São Paulo:
Percentage of intangible and contract assets	43.11%
Percentage of revenue from sanitation services (excluding construction revenue)	44.45%

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details Narrative)	12 Months Ended
	Dec. 31, 2021
IfrsStatementLineItems [Line Items]
Description of accrued income tax	The income tax was accrued at rate of 15%, plus 10% surtax on taxable income exceeding R$ 240
Social contribution accrued rate	9.00%
Annual revenue calculated rate	0.50%
Programa De Formacao Do Patrimonio Do Servidor Publico [Member]
IfrsStatementLineItems [Line Items]
Sanitation services rate	165.00%
Contribuicao Para O Financiamentoda Seguridade Social [Member]
IfrsStatementLineItems [Line Items]
Sanitation services rate	760.00%

New standards and revisions (De

New standards and revisions (Details)	12 Months Ended
	Dec. 31, 2021
I F R S 1 [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IFRS 4 – Insurance Contracts, IFRS 7 – Financial Instruments: Disclosures, IFRS 9 – Financial Instruments, IFRS 16 – Leases
Description	Describes the amendments to the Reference Interest Rate Reform – Phase 2. The adoption of these amendments reflects the effects of the transition from interbank offered rates (“IBOR”) to alternative reference interest rates (also called interest-free rates risk or “risk free rates – RFRs”).
Impact	The application of these amendments did not impact the disclosures or amounts recognized in the annual financial statements.
Amendments To I F R S 10 I A S 28 And [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IFRS 10 - Consolidated Statements and IAS 28 – Sale or Contribution of Assets between an Investor and its Associate or Joint Venture
Description	Clarify situations that involve the sale or contribution of assets between an investor and its associates or joint venture.
Impact	The Company is assessing the impacts and effects of the amendments; however, it does not expect any effects from the amendments.
Standard	Amendment to IFRS 16 – COVID-19 - Related Rent Concessions
Description	Establishes practical measures for lessees in the accounting for lease concessions that occurred as a direct result of COVID-19. Under the practical expedient, a lessee is not required to assess whether a COVID-19-related lease concession is a lease modification.
Impact	The application of this amendment did not impact the disclosures or amounts recognized in the annual financial statements.

The Company did not early adopt

The Company did not early adopt these standards and is assessing the impacts of the new and revised IFRS below on the disclosures or amounts recognized in the financial statements: (Details)	12 Months Ended
	Dec. 31, 2021
I F R S 2 [Member]
IfrsStatementLineItems [Line Items]
Standard	IFRS 17 – Insurance Contracts
Description	Establishes the principles for the recognition, measurement, presentation and disclosure of insurance contracts. IFRS 17 will supersede IFRS 4 Insurance Contracts.
Impact	The Company does not expect effects from adopting this standard.
Amendments To I F R S 10 I A S 28 And [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IFRS 10 - Consolidated Statements and IAS 28 – Sale or Contribution of Assets between an Investor and its Associate or Joint Venture
Description	Clarify situations that involve the sale or contribution of assets between an investor and its associates or joint venture.
Impact	The Company is assessing the impacts and effects of the amendments; however, it does not expect any effects from the amendments.
Amendments To I A S [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IAS 1 – Classification of Liabilities as Current or Non-Current
Description	These amendments to IAS 1 only affect the presentation of liabilities as current or non-current in the statement of financial position and not the amount or the time of recognition of any asset, liability, income or expense, or the information disclosed on such items. In addition, clarify that the classification of liabilities as current or non-current is based on the rights existing at the balance sheet date, specify that the classification is not affected by the expectations on whether an entity will exercise its right to postpone the settlement of the liability and introduce the definition of 'settlement' to clarify that settlement refers to the transfer to a counterparty, of cash, equity instruments, other assets or services.
Impact	The Company does not expect any impacts from this standard.
Amendments To I F R S Three [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IFRS 3 – Reference to the Conceptual Framework
Description	The amendments update IFRS 3 so that it refers to the 2018 Conceptual Framework, not to the 1989 Framework. The amendments also include in IFRS 3 the requirement that, for obligations within the scope of IAS 37, the acquirer applies this standard to identify whether there is an obligation at the acquisition date arising from past events. For a tax within the scope of IFRIC 21 - Taxes, the acquirer applies IFRIC 21 to determine whether the event that resulted in the obligation to pay the tax occurred up to the date of acquisition date. Finally, the amendments add an explicit statement that the acquirer does not recognize contingent assets acquired in a business combination.
Impact	The Company does not expect effects from this standard.
Amendments To I A S Sixteen [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IAS 16 – Proceeds Before Intended Use
Description	The amendments prohibit deducting from the cost of an item of property, plant and equipment any proceeds from the sale of items produced before the asset is available for use, i.e. proceeds to bring the asset to the location and in the condition necessary for it to be able to operate as intended by the Company. Consequently, the entity recognizes these proceeds from the sale and corresponding costs in the result and measures the costs of these items in accordance with IAS 2 - Inventories. The amendments further clarify the meaning of “testing whether an asset is functioning properly”. Currently, IAS 16 determines this as assessing whether the technical and physical performance of the asset is such that it can be used in the production or supply of goods or services, for rent to third parties, or for administrative purposes. If not presented separately in the statement of comprehensive income, the financial statements should disclose the amounts of resources and costs included in income corresponding to items produced that are not a product of the entity's ordinary activities, and which items in the statement of comprehensive income include these resources and costs.
Impact	The Company does not expect effects from this standard.
Amendments To I A S Thirty Seven [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IAS 37 – Onerous Contracts – Cost of Compliance with the Contract1
Description	The amendments specify that the contract's "compliance cost" comprises costs directly related to the contract, which are the incremental costs of compliance with that contract (such as employees or materials) and the allocation of other costs directly related to contract compliance (such as allocation of depreciation expenses for an item of property, plant and equipment used in fulfilling the contract). These amendments apply to contracts for which the entity has not yet fulfilled all of its obligations at the beginning of the annual period in which the entity applies the changes for the first time. Comparative figures are not restated. Instead, the entity must recognize the cumulative effect of the initial adoption of the amendments as an adjustment to the opening balance of retained earnings (or another component of shareholders' equity, as applicable) at the date of first adoption.
Impact	The Company does not expect effects from this standard.
Amendments To I A S Eightheen [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IAS 1 – Presentation of Financial Statements and IFRS Practice Statement 2 – “Making Materiality Judgments” – Disclosure of Accounting Policies4
Description	The amendments modify the requirements contained in IAS 1 regarding the disclosure of accounting policies. The amendments replace all the examples of the term “significant accounting policies” with “relevant accounting policy information”. Accounting policy information is material if, when considered together with other information included in an entity's financial statements, it could reasonably influence the decisions of key users of general purpose financial statements made on the basis of those financial statements. The supporting paragraphs have also been amended to clarify that accounting policy information relating to non-important transactions, other events or conditions is immaterial and need not be disclosed.The Board has also prepared guidance and examples to explain and demonstrate the application of the “four-step materiality process” described in IFRS Practice Statement 2.
Impact	The Company does not expect effects from these amendments.
Amendments To I A S Eight [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IAS 8 - Accounting Policies, Changes in Accounting Estimates and Errors—Definition of Accounting Estimates2
Description	The amendment supersede the definition of change in accounting estimates with the definition of accounting estimates. According to the new definition, accounting estimates are “monetary amounts in the financial statements subject to measurement uncertainty”. The definition of change in accounting estimates was excluded, however, the Board maintained the concept of changes in accounting estimates in the Standard with the following clarifications: • A change in the accounting estimate that results from new information or new events does not mean the correction of an error; • The effects of a change in a data or measurement technique used to develop an accounting estimate correspond to changes in accounting estimates if they do not result from the correction of errors from prior periods.
Impact	The Company does not expect effects from these amendments.
Amendments To I A S Twelve [Member]
IfrsStatementLineItems [Line Items]
Standard	Amendments to IAS 12 – Income Taxes – Deferred Tax Related to Assets and Liabilities Resulting from a Single Transaction (“single transaction”)2
Description	The amendments introduce an additional exception to the exemption of first-time recognition. According to the amendments, an entity does not apply the exemption of first-time recognition for transactions resulting in equal taxable and deductible temporary differences.
Impact	The Company does not expect effects from these amendments.
Amendments To I A S Twenty One [Member]
IfrsStatementLineItems [Line Items]
Standard	Annual improvements to IFRSs: 2018-2020 Cycle Amendments to IFRS 1 – First-time Adoption of International Financial Reporting Standards1, IFRS 9 – Financial Instruments1, IFRS 16 – Leases and IAS 41 – Biological Assets and Agricultural Product1
Description	IFRS 1 – First-Time Adoption of International Accounting Standards - provides for an additional measure for a subsidiary that becomes an initial adopter after its parent company with respect to accounting for accumulated translation differences. IFRS 9 – Financial Instruments - clarifies that when applying the “10%” test to assess whether the financial liability should be written off, the entity includes only the fees paid or received between the entity (debtor) and the creditor, including fees paid or received by the entity or creditor on behalf of the other party. IFRS 16 – Leases - this amendment excludes the example of reimbursement of improvements to third-party properties. Since the amendment is only an illustrative example, no effective date is defined. IAS 41 – Biological Assets and Agricultural Product - the amendment excludes the requirement for entities to exclude cash flows for taxation when measuring fair value.
Impact	The Company does not expect effects from these amendments.

Schedule of exposure to exchang

Schedule of exposure to exchange risk (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Total exposure	R$ 3321489	R$ 3563170
Total foreign currency-denominated borrowings	3,296,153	3,547,862
United States of America, Dollars
IfrsStatementLineItems [Line Items]
Borrowings and financing	912,624	870,338
Interest and charges from borrowings and financing	4,121	5,540
Borrowing cost	(22,486)	(12,342)
Japan, Yen
IfrsStatementLineItems [Line Items]
Borrowings and financing	2,390,774	2,671,255
Interest and charges from borrowings and financing	13,970	16,037
Borrowing cost	(2,850)	(2,966)
Foreign currency | United States of America, Dollars
IfrsStatementLineItems [Line Items]
Borrowings and financing	163,538	167,479
Foreign currency | Japan, Yen
IfrsStatementLineItems [Line Items]
Borrowings and financing	R$ 49324813	R$ 52969560

The table below shows the excha

The table below shows the exchange rate variation for the period: (Details) - R$ / shares	Dec. 31, 2021	Dec. 31, 2020
United States of America, Dollars
IfrsStatementLineItems [Line Items]
Exchange rate	R$ 5.5805	R$ 5.1967
Exchange rate variation	7.40%
Japan, Yen
IfrsStatementLineItems [Line Items]
Exchange rate	R$ 0.04847	R$ 0.05043
Exchange rate variation	(3.90%)

The Company understands that th

The Company understands that the scenario presented is reasonable, given the instability of the Brazilian real against the U.S. dollar and the Yen. (Details) R$ in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)Number	Dec. 31, 2020Number
United States of America, Dollars
IfrsStatementLineItems [Line Items]
Exchange rate estimated according to the scenario	5.5805
Japan, Yen
IfrsStatementLineItems [Line Items]
Exchange rate estimated according to the scenario	0.04847	0.05043
Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
Total effect on net financial result in R$ - gain/(loss) | R$	R$ 124528
Probable Scenario [Member] | United States of America, Dollars
IfrsStatementLineItems [Line Items]
Net currency exposure | R$	R$ 163538
Currency rate	5.5805
Exchange rate estimated according to the scenario	5.6000
Differences between the rates	1.95%
Effect on net financial result R$ - gain/(loss) | R$	R$ 3189
Probable Scenario [Member] | Japan, Yen
IfrsStatementLineItems [Line Items]
Net currency exposure | R$	R$ 49324813
Currency rate	0.04847
Exchange rate estimated according to the scenario	0.05093
Differences between the rates	(0.246%)
Effect on net financial result R$ - gain/(loss) | R$	R$ 121339

The table below provides the Co

The table below provides the Company's borrowings and financing subject to variable interest rates: (Details) - BRL (R$) R$ in Thousands		Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Borrowings		R$ 14904899	R$ 14185384
Certificado De Deposito Interbancario [Member]
IfrsStatementLineItems [Line Items]
Borrowings	[1]	7,612,299	7,836,988
Interest Benchmark Rates [Member]
IfrsStatementLineItems [Line Items]
Borrowings	[2]	1,638,079	1,619,416
Indice Nacional De Precos Ao Consumidor Amplos [Member]
IfrsStatementLineItems [Line Items]
Borrowings	[3]	3,019,459	2,176,547
Taxa De Juros A Longo Prazos [Member]
IfrsStatementLineItems [Line Items]
Borrowings	[4]	1,478,740	1,517,657
London Interbank Offered Rates [Member]
IfrsStatementLineItems [Line Items]
Borrowings	[5]	912,626	870,337
Interest And Charge [Member]
IfrsStatementLineItems [Line Items]
Borrowings		R$ 243696	R$ 164439
[1]	CDI – (Certificado de Depósito Interbancário), an interbank deposit certificate
[2]	TR – Interest Benchmark Rate
[3]	IPCA – (Índice Nacional de Preços ao Consumidor Amplo), a consumer price index
[4]	TJLP – (Taxa de Juros a Longo Prazo), a long-term interest rate index
[5]	LIBOR – London Interbank Offered Rate

For the credit quality of the b

For the credit quality of the banks, such as deposits and financial investments, the Company considers the lower rating published by three main international rating agencies (Fitch, Moody's and S&P), according to internal policy of market risk management: (Details)	12 Months Ended
	Dec. 31, 2021
Banco De Brasil [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA.br
Banco De Brasil [Member] | Fitch [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AA(bra)
Banco Santander Brasil [Member] | Standard Poors [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	brAAA
Banco Santander Brasil [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA.br
Caixa Economica Federal [Member] | Standard Poors [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	brAAA
Caixa Economica Federal [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA.br
Caixa Economica Federal [Member] | Fitch [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AA(bra)
Banco Bradesco [Member] | Standard Poors [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	brAAA
Banco Bradesco [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA.br
Banco Bradesco [Member] | Fitch [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA(bra)
Itau Unibanco Holding [Member] | Standard Poors [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	brAAA
Itau Unibanco Holding [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA.br
Itau Unibanco Holding [Member] | Fitch [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA(bra)
Banco B V [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AA.br
Banco B V [Member] | Standard Poors [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	brAAA
Banco B T G Pactual S [Member] | Fitch [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AA(bra)
Banco B T G Pactual S [Member] | Moodys [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	AAA.br
Banco B T G Pactual S [Member] | Standard Poors [Member]
IfrsStatementLineItems [Line Items]
Credit rating information of the banks	brAA+

The table below shows the ratin

The table below shows the rating assessment released by the Fitch agency, for deposit transactions and financial investments in local currency (R$ - domestic rating): (Details) - BRL (R$) R$ in Thousands		Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Cash and cash equivalents and financial investments		R$ 3151314	R$ 3807547
Banco B V [Member]
IfrsStatementLineItems [Line Items]
Current accounts and investment funds		262,465	253,066
A A Plus Bra [Member]
IfrsStatementLineItems [Line Items]
Cash and cash equivalents and financial investments		1,905,810	2,662,685
A A A Bra [Member]
IfrsStatementLineItems [Line Items]
Cash and cash equivalents and financial investments		970,474	891,243
Others [Member]
IfrsStatementLineItems [Line Items]
Cash and cash equivalents and financial investments	[1]	R$ 275030	R$ 253619
[1]	This category includes current accounts and financial investmets in banks referring to Banco BV in the amount of R$ 262,465 253,066

For agreements with floating in

For agreements with floating interest rate, the interest rates used correspond to the base dates above. (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Borrowings and financing	R$ 26639575
Trade payables and contractors	236,763
Services payable	469,027	R$ 453750
Public-Private Partnership – PPP	6,011,704
Program Contract Commitments	130,268
Twenty Twenty Two [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	2,767,867
Trade payables and contractors	236,763
Services payable	469,027
Public-Private Partnership – PPP	429,942
Program Contract Commitments	77,465
Twenty Twenty Three [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	2,749,335
Trade payables and contractors
Services payable
Public-Private Partnership – PPP	430,440
Program Contract Commitments	36,442
Twenty Twenty Four [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	2,939,155
Trade payables and contractors
Services payable
Public-Private Partnership – PPP	379,684
Program Contract Commitments	1,126
Twenty Twenty Five [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	2,976,535
Trade payables and contractors
Services payable
Public-Private Partnership – PPP	351,586
Program Contract Commitments	1,126
Twenty Twenty Six [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	2,721,792
Trade payables and contractors
Services payable
Public-Private Partnership – PPP	351,586
Program Contract Commitments	1,126
Twenty Twenty Seven [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	12,484,891
Trade payables and contractors
Services payable
Public-Private Partnership – PPP	4,068,466
Program Contract Commitments	R$ 12983

The purpose of the sensitivity

The purpose of the sensitivity analysis is to measure the impact of changes in the market over the financial instruments, considering constant all other variables. In the time of settlement the amounts can be different from those presented, due to the est (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Exposure interest rate risk	R$ 3321489	R$ 3563170
Interest rate risk [member] | Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
Liabilities	(969,137)
Exposure interest rate risk	(716,677)
Interest rate risk [member] | Probable Scenario [Member] | Financial Income [Member]
IfrsStatementLineItems [Line Items]
Assets	180,813
Interest rate risk [member] | Scenario I [Member] | Interest To Be Incurred [Member]
IfrsStatementLineItems [Line Items]
Liabilities	(897,490)
Interest rate risk [member] | C D I [Member] | Exposure [Member]
IfrsStatementLineItems [Line Items]
Assets	1,533,614
Liabilities	(7,612,299)
Exposure interest rate risk	R$ 6078685
Interest rate risk [member] | C D I [Member] | Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
[custom:InterestRatesDuringTheYear1-0]	11.79%
[custom:InterestRatesDuringTheYear-0]	11.79%
Interest rate risk [member] | T R [Member] | Exposure [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 1638079
Interest rate risk [member] | T R [Member] | Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
[custom:InterestRatesDuringTheYear-0]	0.0276%
Interest rate risk [member] | T R [Member] | Probable Scenario [Member] | Expenses To Be Incurred [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 452
Interest rate risk [member] | I P C A [Member] | Exposure [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 3019459
Interest rate risk [member] | I P C A [Member] | Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
[custom:InterestRatesDuringTheYear-0]	5.0302%
Interest rate risk [member] | I P C A [Member] | Probable Scenario [Member] | Expenses To Be Incurred [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 151885
Interest rate risk [member] | T J L P [Member] | Exposure [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 1478740
Interest rate risk [member] | T J L P [Member] | Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
[custom:InterestRatesDuringTheYear-0]	6.44%
Interest rate risk [member] | T J L P [Member] | Probable Scenario [Member] | Interest To Be Incurred [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 95231
Interest rate risk [member] | L I B O R [Member] | Exposure [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 912626
Interest rate risk [member] | L I B O R [Member] | Probable Scenario [Member]
IfrsStatementLineItems [Line Items]
[custom:InterestRatesDuringTheYear-0]	0.536%
Interest rate risk [member] | L I B O R [Member] | Probable Scenario [Member] | Interest To Be Incurred [Member]
IfrsStatementLineItems [Line Items]
Liabilities	R$ 4892

Total capital is calculated as

Total capital is calculated as total equity as shown in the statement of the financial position plus net debt. (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Total borrowings and financing (Note 17)	R$ 17723836	R$ 17258624	R$ 13244709	R$ 13152796
(-) Cash and cash equivalents (Note 7)	(717,929)	(396,401)
(-) Financial investments (Note 8)	2,433,385	3,411,146
Net debt	14,572,522	13,451,077
Total equity	24,931,859	22,793,704	R$ 21635783	R$ 19551688
Total capital (shareholders + providers of capital)	R$ 39504381	R$ 36244781
Leverage ratio	37.00%	37.00%

The estimated fair values of th

The estimated fair values of the financial instruments are as follows: (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Cash and cash equivalents	R$ 717929	R$ 396401	R$ 2253210	R$ 3029191
Financial investments	2,433,385	3,411,146
Restricted cash	28,467	35,742
Trade receivables	2,918,311	2,450,986
Water National Agency - ANA	20,666	26,463
Other receivables	226,242	246,110
Fair Values [Member]
IfrsStatementLineItems [Line Items]
Cash and cash equivalents	717,929	396,401
Financial investments	2,433,385	3,411,146
Restricted cash	28,467	35,742
Trade receivables	2,918,311	2,450,986
Water National Agency - ANA	20,666	26,463
Other receivables	R$ 226242	R$ 246110

Financial liabilities (Details)

Financial liabilities (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Borrowings and financing	R$ 17723836	R$ 17258624	R$ 13244709	R$ 13152796
Accounts payables to suppliers and contractors	236,763	263,741
Services payable	469,027	453,750
Program contract commitments	122,647	231,480
Public-Private Partnership - PPP	3,060,185	3,175,273
Fair Values [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing	17,947,954	17,702,649
Accounts payables to suppliers and contractors	236,763	263,741
Services payable	469,027	453,750
Program contract commitments	122,647	231,480
Public-Private Partnership - PPP	R$ 3060185	R$ 3175273

Cash and cash equivalents (Deta

Cash and cash equivalents (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash and banks	R$ 146853	R$ 74033
Cash equivalents	571,076	322,368
Total	R$ 717929	R$ 396401	R$ 2253210	R$ 3029191

Risk Management (Details Narrat

Risk Management (Details Narrative) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Total exposure	R$ 3321489	R$ 3563170
Percentage of decrease in currency due to debt	7.10%
Liabilities related to exchange rate variation of borrowings and financing contracts	R$ 251709	2,811
Income before taxes	332,149	356,317
Effects on profit for the year before taxes	R$ 149049	R$ 141854
Leverage ratio	37.00%	37.00%
Financial instrument assets receivables from related parties	R$ 818552	R$ 806645
Reimbursement of additional retirement and pension plan	R$ 741910	R$ 732391

Cash and cash equivalents (De_2

Cash and cash equivalents (Details Narrative)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Certificado De Deposito Interbancario [Member]
IfrsStatementLineItems [Line Items]
Average yield of cash equivalents	0.9600	0.9582

The Company has financial inves

The Company has financial investments in CDB, with daily liquidity, which it does not intend to use in the next three months, as shown below: (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Financial investments	R$ 2433385	R$ 3411146
Banco B V [Member]
IfrsStatementLineItems [Line Items]
Financial investments	262,465	253,066
Banco Itau S A [Member]
IfrsStatementLineItems [Line Items]
Financial investments	366,906	354,296
Banco Bradesco S A [Member]
IfrsStatementLineItems [Line Items]
Financial investments	524,791	506,136
Banco B T G Pactual S A [Member]
IfrsStatementLineItems [Line Items]
Financial investments	367,361	354,299
Bancodobrasilsa One [Member]
IfrsStatementLineItems [Line Items]
Financial investments	R$ 911862	R$ 1943349

Financial investments (Details

Financial investments (Details Narrative)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Certificado De Deposito Interbancario [Member]
IfrsStatementLineItems [Line Items]
Average yield of financial investments	101.57%	98.95%

Schedule of restricted cash (De

Schedule of restricted cash (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Restricted cash	R$ 28467	R$ 35742
Agreementwiththe Sao Paulo Municipal Government [Member]
IfrsStatementLineItems [Line Items]
Restricted cash	21,464	29,599
Brazilian Federal Savings Bank Escrow Deposites [Member]
IfrsStatementLineItems [Line Items]
Restricted cash	740	272
Other One [Member]
IfrsStatementLineItems [Line Items]
Restricted cash	R$ 6263	R$ 5871

Schedule of financial position

Schedule of financial position (Details) - BRL (R$) R$ in Thousands		Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Subtotal		R$ 4198399	R$ 3608605
Allowance for doubtful accounts		(1,280,088)	(1,157,619)
Total trade receivables		2,918,311	2,450,986
Current		2,695,077	2,204,029
Noncurrent		223,234	246,957
Trade receivables		2,918,311	2,450,986
Unbilled Supply [Member]
IfrsStatementLineItems [Line Items]
Subtotal		740,193	713,310
Private Sector [Member]
IfrsStatementLineItems [Line Items]
Subtotal		2,556,639	2,062,105
Private Sector [Member] | General And Special Customers [Member]
IfrsStatementLineItems [Line Items]
Subtotal	[1],[2]	2,042,023	1,663,738
Private Sector [Member] | Agreements [Member]
IfrsStatementLineItems [Line Items]
Subtotal	[3]	514,616	398,367
Government Entities [Member]
IfrsStatementLineItems [Line Items]
Subtotal		873,523	810,800
Government Entities [Member] | Agreements [Member]
IfrsStatementLineItems [Line Items]
Subtotal		278,844	333,740
Government Entities [Member] | Municipal [Member]
IfrsStatementLineItems [Line Items]
Subtotal		586,810	473,201
Government Entities [Member] | Federal [Member]
IfrsStatementLineItems [Line Items]
Subtotal		7,869	3,859
Wholesale Municipal Governments [Member]
IfrsStatementLineItems [Line Items]
Subtotal		28,044	22,390
Wholesale Municipal Governments [Member] | Mogi Das Cruzes [Member]
IfrsStatementLineItems [Line Items]
Subtotal	[4]	3,580	3,582
Wholesale Municipal Governments [Member] | Sao Caetano Do Sul [Member]
IfrsStatementLineItems [Line Items]
Subtotal	[4]	R$ 24464	R$ 18808
[1]	General customers - residential and small and mid-sized companies;
[2]	Special customers - large consumers, commercial, industries, condominiums and special billing customers (fixed demand agreements, industrial waste, wells, among others);
[3]	Agreements - installment payments of past-due receivables, plus monetary adjustment and interest, according to the agreements;
[4]	Wholesale basis customers - municipal governments - This balance refers to invoices issued as a result of services provided to municipalities, which are responsible for distributing to, billing and charging final customers.

Schedule of aging of trade rece

Schedule of aging of trade receivables (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Current	R$ 1896535	R$ 1793104
Past-due	2,301,864	1,815,501
Total	4,198,399	3,608,605
Not later than one month [member]
IfrsStatementLineItems [Line Items]
Past-due	502,164	340,760
Later than one month and not later than two months [member]
IfrsStatementLineItems [Line Items]
Past-due	267,723	177,103
Later Than Two Month And Not Later Than Three Months [Member]
IfrsStatementLineItems [Line Items]
Past-due	182,977	120,488
Later Than Three Month And Not Later Than Four Months [Member]
IfrsStatementLineItems [Line Items]
Past-due	155,018	88,323
Later Than Four Month And Not Later Than Six Months [Member]
IfrsStatementLineItems [Line Items]
Past-due	258,718	113,060
Later than six months and not later than one year [member]
IfrsStatementLineItems [Line Items]
Past-due	95,751	82,365
Later than one year [member]
IfrsStatementLineItems [Line Items]
Past-due	R$ 839513	R$ 893402

Schedule of allowance for doubt

Schedule of allowance for doubtful accounts (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance at beginning of the year	R$ 1157619	R$ 1042015	R$ 1099442
Additions	(182,547)	(176,776)	(54,064)
Recoveries	(60,078)	(61,172)	(111,491)
Balance at the end of the year	R$ 1280088	R$ 1157619	R$ 1042015

Schedule of reconciliation of e

Schedule of reconciliation of estimated/historic losses of income (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Write-offs	R$ 508055	R$ 329512	R$ 179929
(Losses)/reversal with state entities - related parties	(13,206)	290	(5,597)
(Losses) with the private sector / government entities	(182,547)	(176,776)	(54,064)
Recoveries	60,078	61,172	111,491
Amount recorded expense (Note 29)	R$ 643730	R$ 444826	R$ 128099

Schedule of loan agreement thro

Schedule of loan agreement through credit facility (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2015
IfrsStatementLineItems [Line Items]
Accounts receivable, current	R$ 173657	R$ 168054		R$ 696283
Accounts receivable, noncurrent	644,895	638,591
Total receivables from shareholders	818,552	806,645
Assets	53,165,485	50,418,636
Liabilities	28,233,626	27,624,932
Revenues	19,491,061	17,797,541	R$ 17983654
Sanitation Services 1 [Member]
IfrsStatementLineItems [Line Items]
Revenues	522,608	501,756	556,574
Payments Received Related Parties [Member]
IfrsStatementLineItems [Line Items]
Revenues	(439,349)	(520,881)	(546,365)
Receipt Of Reimbursement Referring To Law [Member]
IfrsStatementLineItems [Line Items]
Receipt of GESP reimbursement	(179,787)	(173,874)	R$ 152112
Sanitation Services [Member]
IfrsStatementLineItems [Line Items]
Accounts receivable, current	127,614	109,078
Assets	76,642	74,254
Allowance For Loss [Member]
IfrsStatementLineItems [Line Items]
Accounts receivable, current	(52,333)	(39,127)
Monthly Flow Paymentsiiandvi [Member]
IfrsStatementLineItems [Line Items]
Accounts receivable, current	11,930	22,726
Reimbursement G E S P 2015 [Member]
IfrsStatementLineItems [Line Items]
Accounts receivable, current	86,446	75,377
Accounts receivable, noncurrent	643,534	634,288
Agreement For The Installment Payment Of Sanitation Services [Member]
IfrsStatementLineItems [Line Items]
Accounts receivable, noncurrent	1,361	4,303
Assets		732,391
Liabilities		R$ 116180
Reimbursement For Retirement And Pension Benefits Paid [Member]
IfrsStatementLineItems [Line Items]
Assets	741,910
Liabilities	R$ 275240

Related-Party Balances and Tr_3

Related-Party Balances and Transactions (Details Narrative) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 05, 2017	Mar. 31, 2015	Mar. 18, 2015	Nov. 17, 2008
IfrsStatementLineItems [Line Items]
Accounts receivable, current	R$ 173657	R$ 168054			R$ 696283
Undisputed reimbursement							R$ 915251
Reimbursement receivable related to the reservoirs							696,283
Remaining debit balance							R$ 218967
Agreement transaction amount						R$ 1012310
Inflation adjustment amount						R$ 316027
Number of shares issued	683,509,869	683,509,869	683,509,869
Monthly installment payable				R$ 609109
Receivables in current assets	R$ 86446	R$ 75377
Receivables in non-current assets	643,534	634,288
Disputed amounts receivable	1,375,137	1,281,409
Actuarial liability amount	2,192,062	2,549,541
Other liabilities, current	7,956	17,255
Other liabilities, non-current	88,264	73,660
Expenses related to personnel assigned by SABESP to other state government entities	734	2,108	R$ 4881
Expenses related to personnel by other entities to SABESP		13	139
Non-operating assets	3,613	3,613
Net actuarial liability	129,600	319,053
Compensation to Officers	6,369	6,426
Bonus program	1,440	1,439
Total loan agreement related party	11,884	9,420
Total loan agreement related party	11,021	R$ 23866
Total loan agreement related party	34
Total loan agreement related party	1,009
Total investment amount	10,800,000
Investment financed by FEHIDRO	8,700,000
Investment financed by SABESP	R$ 2100000
Financing interest rate	3.00%
Preference shares [member]
IfrsStatementLineItems [Line Items]
Number of shares issued		2,221,000
Value of shares issued	R$ 87174
Allowance For Losses [Member]
IfrsStatementLineItems [Line Items]
Accounts receivable, current	R$ 52333	R$ 39127	R$ 39417

Schedule of the investees' fina

Schedule of the investees' financial statements and equity interest (Details) - BRL (R$) R$ in Thousands	Aug. 20, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Equity		R$ 24931859	R$ 22793704	R$ 21635783	R$ 19551688
Profit for the year		2,305,869	973,318	3,367,517
Investments		73,338	57,318
Dividends distributed		548,006	231,611
Equity in the earnings of subsidiaries		18,780	14,136	3,701
Equity in the earnings of subsidiaries - change in the equity		3,299
Other comprehensive income		447,376	511,169	R$ 363076
Reclassification into held-to-maturity investments			(1,203)
Other investments		6,099	6,099
Overall total		R$ 79437	R$ 63417
Number of shares issued		683,509,869	683,509,869	683,509,869
Seasamm [Member]
IfrsStatementLineItems [Line Items]
Equity		R$ 58421	R$ 51514	R$ 45923
Dividend distributed		(2,152)
Profit for the year		9,059	7,332	4,418
Profit for the year - change in the equity
Investments		21,032	18,546
Dividends distributed		(775)
Equity in the earnings of subsidiaries		R$ 3261	R$ 2640	R$ 1591
Interest percentage		36.00%	36.00%	36.00%
Aguas De Andradinas [Member]
IfrsStatementLineItems [Line Items]
Equity		R$ 29591	R$ 29576	R$ 30065
Dividend distributed		(2,320)
Profit for the year		2,424	778	7,271
Profit for the year - change in the equity		(89)
Investments		8,877	8,873
Dividends distributed		(696)
Equity in the earnings of subsidiaries		R$ 727	R$ 233	R$ 2181
Interest percentage		30.00%	30.00%	30.00%
Equity in the earnings of subsidiaries - change in the equity		R$ 27
Other comprehensive income		17
Aguas De Castilho [Member]
IfrsStatementLineItems [Line Items]
Equity		9,384	R$ 8533	R$ 7242
Dividend distributed		(592)
Profit for the year		1,428	1,613	1,767
Profit for the year - change in the equity		15
Investments		2,815	2,560
Dividends distributed		(178)
Equity in the earnings of subsidiaries		R$ 429	R$ 485	R$ 529
Interest percentage		30.00%	30.00%	30.00%
Equity in the earnings of subsidiaries - change in the equity		R$ 4
Saneaqua Mairinque [Member]
IfrsStatementLineItems [Line Items]
Equity			R$ 4013	R$ 4783
Dividend distributed
Profit for the year			(770)	(871)
Profit for the year - change in the equity
Equity in the earnings of subsidiaries			R$ 248	R$ 262
Interest percentage		4.06%	4.06%	30.00%
Reclassification into held-to-maturity investments			R$ 1203
Capital increase	R$ 21944
Number of shares issued	17,178,988
Other investments	R$ 5734
Attend Ambiental [Member]
IfrsStatementLineItems [Line Items]
Equity		R$ 23493	11,409	R$ 7486
Dividend distributed
Profit for the year		4,701	3,923	(18,217)
Profit for the year - change in the equity		7,383
Investments		10,572	5,134
Equity in the earnings of subsidiaries		R$ 2116	R$ 1765	R$ 8198
Interest percentage		45.00%	45.00%	45.00%
Equity in the earnings of subsidiaries - change in the equity		R$ 3322
Reclassification into held-to-maturity investments
Aquapolo Ambiental [Member]
IfrsStatementLineItems [Line Items]
Equity		58,172	41,903	R$ 37772
Dividend distributed		(9,000)
Profit for the year		25,269	19,131	16,283
Profit for the year - change in the equity
Investments		28,504	20,532
Dividends distributed		(4,410)
Equity in the earnings of subsidiaries		R$ 12382	R$ 9374	R$ 7979
Interest percentage		49.00%	49.00%	49.00%
Paulista Geradora De Energias [Member]
IfrsStatementLineItems [Line Items]
Equity		R$ 6153	R$ 6692	R$ 7144
Dividend distributed
Profit for the year		(539)	(452)	(481)
Profit for the year - change in the equity
Paulista Geradora De Energi [Member]
IfrsStatementLineItems [Line Items]
Investments		1,538	1,673
Equity in the earnings of subsidiaries		R$ 135	R$ 113	R$ 119
Interest percentage		25.00%	25.00%	25.00%

Schedule of investment properti

Schedule of investment properties (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment properties, ending	R$ 46126	R$ 46274	R$ 47562	R$ 47620
Write-offs and disposals	(100)
Depreciation	R$ 48	(48)	(49)
Transfers		R$ 1240	R$ 9

Investments (Details Narrative)

Investments (Details Narrative) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Capital stock	R$ 15000000	R$ 15000000
Capital stock, shares	683,509,869
Seasamm [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 19532
Capital stock, shares	19,532,409
Equity interest	36.00%
G S Inima [Member]
IfrsStatementLineItems [Line Items]
Equity interest	64.00%
Aguas De Andradina [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 17936
Capital stock, shares	17,936,174
S A B E S P [Member]
IfrsStatementLineItems [Line Items]
Equity interest	30.00%
Igua Saneamento S A [Member]
IfrsStatementLineItems [Line Items]
Equity interest	70.00%
Percentage of equity interest held	70.00%
Aguas De Castilho [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 2785
Capital stock, shares	2,785,225
Aquapolo Ambiental [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 36412
Capital stock, shares	42,419,045
Paulista Geradora De Energia [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 8679
Capital stock, shares	8,679,040
Equity interest	25.00%
Servtec Investimentos E Participacoes Ltda [Member]
IfrsStatementLineItems [Line Items]
Percentage of equity interest held	37.50%
Tecniplan Engenharia E Comercio Ltda [Member]
IfrsStatementLineItems [Line Items]
Percentage of equity interest held	37.50%

Investment properties (Details

Investment properties (Details Narrative) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investment properties, market value	R$ 386000	R$ 383000

Schedule of contract assets (De

Schedule of contract assets (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021		Dec. 31, 2020	Dec. 31, 2019
Contract assets, beginning	R$ 7969164		R$ 7617714	R$ 7407948
Additions	4,759,789	[1]	3,948,158	3,532,283
Transfers	2,412			10,710
Transfers of works to intangible assets	(4,181,263)	[2]		(3,328,317)
Contract assets, ending	8,550,102	[3]	7,969,164	7,617,714
Contract assets, beginning	R$ 7969164		7,617,714
Additions			3,984,158
Transfers			55,706
Transfers of works to intangible assets			(3,688,414)
[custom:ContractAssets4-2]			R$ 7969164	7,617,714
Write-offs				R$ 4910
[1]	The largest additions of the period are located in the municipalities of São Paulo, Guarulhos and Praia Grande, in the amounts of R$ 2,419 million, R$ 180 million and R$ 158 million, respectively.
[2]	The largest transfers of the period are located in the municipalities of São Paulo, Itaquaquecetuba and São Bernardo do Campo, in the amounts of R$ 2,270 million, R$ 199 million and R$ 180 million, respectively.
[3]	The largest works are located in the municipalities of São Paulo, Praia Grande and São Bernardo do Campo, in the amounts of R$ 3,955 million, R$ 634 million and R$ 407 million, respectively.

Contract assets (Details Narrat

Contract assets (Details Narrative) - BRL (R$)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Contract assets,includes leases	R$ 276893	R$ 276893
foreign currency exchange effects in the contract asset	300,792	238,330	R$ 233251
Construction margin	98,402	86,477	R$ 65172
Contracts assets	R$ 67714	R$ 33136

Statement of financial positi_2

Statement of financial position details (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Cost	R$ 52850974	R$ 48687584
Accumulated amortization	(16,347,140)	(14,282,009)
Net	36,503,834	34,405,575	R$ 32325447	R$ 29012460
Agreements Equity Values [Member]
IfrsStatementLineItems [Line Items]
Cost	696,728	671,904
Accumulated amortization	(205,671)	(188,129)
Net	491,057	483,775
Agreements Economic Value [Member]
IfrsStatementLineItems [Line Items]
Cost	1,497,968	1,446,261
Accumulated amortization	(816,527)	(711,596)
Net	681,441	734,665	712,852	1,232,009
Program Contractses [Member]
IfrsStatementLineItems [Line Items]
Cost	24,804,170	23,160,119
Accumulated amortization	(7,652,149)	(6,799,812)
Net	17,152,021	16,360,307
Program Contract Commitments [Member]
IfrsStatementLineItems [Line Items]
Cost	1,709,757	1,709,757
Accumulated amortization	(391,800)	(338,834)
Net	1,317,957	1,370,923
Service Contracts Commitments [Member]
IfrsStatementLineItems [Line Items]
Cost	22,834,803	20,579,676
Accumulated amortization	(6,676,032)	(5,707,072)
Net	16,158,771	14,872,604	R$ 14390763	R$ 13391452
Software Licenses [Member]
IfrsStatementLineItems [Line Items]
Cost	1,133,833	978,085
Accumulated amortization	(535,099)	(437,460)
Net	598,734	540,625
Right Of Uses [Member]
IfrsStatementLineItems [Line Items]
Cost	173,715	141,782
Accumulated amortization	(69,862)	(99,106)
Net	R$ 103853	R$ 42676

The obligations assumed by the

The obligations assumed by the Company as of December 31, 2021 and 2020 are shown in the table below: (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 30, 2020	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Intangible assets, beginning	R$ 34405575
Additions	172,961	R$ 411285	R$ 1723952
Transfer of contract assets	4,181,263	3,688,414	3,328,317
Transfers	370	2,991	(13,531)
Write-offs and disposals	(27,078)	(16,313)	(39,931)
Amortization	(2,229,257)	(2,006,249)	(1,746,430)
Intangible assets, ending	36,503,834	34,405,575
Right of use	626,427	589,130
Intangible assets, beginning	34,405,575	32,325,447	29,012,460
Contract renewal
Intangible assets, ending	36,503,834	34,405,575	32,325,447
Intangible assets, ending	36,503,834	34,405,575	32,325,447		R$ 29012460
Transfer to indemnities receivable			(4,345)
First-time adoption of IFRS 16			64,955
Current liabilities	142,757	130,207
Noncurrent liabilities	2,917,428	3,045,066
Total liabilities	3,060,185	3,175,273
Alto Tiete [Member]
IfrsStatementLineItems [Line Items]
Current liabilities	69,442	59,429
Noncurrent liabilities	102,873	149,726
Total liabilities	172,315	209,155
Sao Lourenco [Member]
IfrsStatementLineItems [Line Items]
Current liabilities	73,315	70,778
Noncurrent liabilities	2,814,555	2,895,340
Total liabilities	2,887,870	2,966,118
Leases Related To Concession Agreements And Program Contract [Member]
IfrsStatementLineItems [Line Items]
Right of use	245,681	269,561	292,824		315,717
Concession Agreements [Member]
IfrsStatementLineItems [Line Items]
Right of use	65,012	76,454	87,266		98,077
Program Contracts [Member]
IfrsStatementLineItems [Line Items]
Right of use	180,669	193,107	205,558		217,640
Agreements Equity Value [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		483,775
Additions		1	2
Transfer of contract assets	24,656	47,154	131,809
Transfers	467	1,440	76,804
Write-offs and disposals	(148)	(858)	(8,311)
Amortization	(17,693)	(26,985)	(83,790)
Intangible assets, ending	491,057		483,775
Intangible assets, beginning	483,775	1,494,853	4,073,344
Contract renewal		(1,031,830)	(2,690,660)
Intangible assets, ending		483,775	1,494,853
Intangible assets, ending		483,775	1,494,853		4,073,344
Transfer to indemnities receivable			(4,345)
Agreements Economic Value [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		734,665
Additions			2,034
Transfer of contract assets	52,275	113,320	89,041
Transfers	(14)	(1,403)	1,956
Write-offs and disposals	(242)	(42)	(569)
Amortization	(105,243)	(90,062)	(79,446)
Intangible assets, ending	681,441		734,665
Intangible assets, beginning	734,665	712,852	1,232,009
Contract renewal			(532,173)
Intangible assets, ending	681,441	734,665	712,852
Intangible assets, ending	681,441	734,665	712,852		1,232,009
Program Contracts [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		16,360,307
Additions	17,690	303,472	1,338,443
Transfer of contract assets	1,640,733	2,075,268	970,534
Transfers	13,744	(51,570)	137,283
Write-offs and disposals	(8,840)	(5,423)	(10,312)
Amortization	(871,613)	(812,970)	(617,950)
Intangible assets, ending	17,152,021		16,360,307
Intangible assets, beginning	16,360,307	13,819,700	8,777,929
Contract renewal		1,031,830	3,223,773
Intangible assets, ending		16,360,307	13,819,700
Intangible assets, ending		16,360,307	13,819,700	R$ 13819700	8,777,929
Program Contracts Commitments [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		1,370,923
Additions		58,323	331,328
Transfer of contract assets
Transfers
Write-offs and disposals
Amortization	(52,966)	(52,275)	(46,004)
Intangible assets, ending	1,317,957		1,370,923
Intangible assets, beginning	1,370,923	1,364,875	1,079,551
Intangible assets, ending		1,370,923	1,364,875
Intangible assets, ending		1,370,923	1,364,875		1,079,551
Service Contracts Commitments [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		14,872,604
Additions	14,950	20,940	3,867
Transfer of contract assets	2,307,851	1,382,656	2,054,940
Transfers	(13,827)	(23,645)	(228,583)
Write-offs and disposals	(13,745)	(9,990)	(20,739)
Amortization	(1,009,062)	(888,120)	(809,234)
Intangible assets, ending	16,158,771		14,872,604
Intangible assets, beginning	14,872,604	14,390,763	13,391,452
Contract renewal			(940)
Intangible assets, ending	16,158,771	14,872,604	14,390,763
Intangible assets, ending	16,158,771	14,872,604	14,390,763		13,391,452
Software License [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		540,625
Additions
Transfer of contract assets		70,016	81,993
Transfers		78,169	(991)
Write-offs and disposals
Amortization	(97,639)	(79,266)	(67,471)
Intangible assets, ending	598,734		540,625
Transfers to contract assets	155,748
Intangible assets, beginning	540,625	471,706	458,175
Intangible assets, ending		540,625	471,706
Intangible assets, ending		540,625	471,706		458,175
Right Of Use Other Assets [Member]
IfrsStatementLineItems [Line Items]
Intangible assets, beginning		42,676
Additions	140,321	28,549	48,278
Transfer of contract assets
Transfers
Write-offs and disposals	(4,103)
Amortization	(75,041)	(56,571)	(42,535)
Intangible assets, ending	103,853		42,676
Intangible assets, beginning	R$ 42676	70,698
Intangible assets, ending		42,676	70,698
Intangible assets, ending		R$ 42676	70,698
First-time adoption of IFRS 16			R$ 64955

Right of use (Details)

Right of use (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Right of use	R$ 626427	R$ 589130
Right of use	103,853	42,676
Leases Related To Contract Asset [Member]
IfrsStatementLineItems [Line Items]
Right of use	276,893	276,893
Leases Related To Concession Agreements And Program Contract [Member]
IfrsStatementLineItems [Line Items]
Right of use	245,681	269,561	R$ 292824	R$ 315717
Leases Related To Concession Agreements And Program Contract [Member] | Costs [Member]
IfrsStatementLineItems [Line Items]
Right of use	405,446	405,426
Leases Related To Concession Agreements And Program Contract [Member] | Accumulated Amortizations [Member]
IfrsStatementLineItems [Line Items]
Right of use	(159,765)	(135,865)
Vehicles [member]
IfrsStatementLineItems [Line Items]
Right of use	142,003	115,208
Properties [Member]
IfrsStatementLineItems [Line Items]
Right of use	6,570	15,508
Office equipment [member]
IfrsStatementLineItems [Line Items]
Right of use	9,841	4,541
Other assets [member]
IfrsStatementLineItems [Line Items]
Right of use	15,301	6,525
Accumulated Amortization [Member]
IfrsStatementLineItems [Line Items]
Right of use	R$ 69862	R$ 99106

The table below shows the impac

The table below shows the impact in the income statements: (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Right-of-use amortization	R$ 75041	R$ 79834	R$ 65413
Financial result – interest expenses	68,730	62,956	54,791
Short-term and low-value lease expenses	22,467	13,845	51,855
Decrease of the income of the year	R$ 166238	R$ 156635	R$ 172059

Schedule of statement of financ

Schedule of statement of financial position details (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Cost	R$ 637675	R$ 602345
Net	R$ 291157	R$ 268251	R$ 314393	R$ 267612
Depreciation average rate	11.10%	11.20%
Accumulated amortization	R$ 346518	R$ 334094
Land [member]
IfrsStatementLineItems [Line Items]
Cost	94,213	94,213
Net	R$ 94213	R$ 94213
Depreciation average rate
Accumulated amortization
Buildings [member]
IfrsStatementLineItems [Line Items]
Cost	R$ 86703	86,860
Net	R$ 45498	R$ 45347
Depreciation average rate	2.10%	2.10%
Accumulated amortization	R$ 41205	R$ 41513
Office equipment [member]
IfrsStatementLineItems [Line Items]
Cost	397,782	372,103
Net	R$ 115154	R$ 101016
Depreciation average rate	15.10%	14.80%
Accumulated amortization	R$ 282628	R$ 271087
Transport Equipments [Member]
IfrsStatementLineItems [Line Items]
Cost	10,434	10,319
Net	R$ 2472	R$ 2969
Depreciation average rate	9.90%	9.90%
Accumulated amortization	R$ 7962	R$ 7350
Fixtures and fittings [member]
IfrsStatementLineItems [Line Items]
Cost	36,561	31,232
Net	R$ 22079	R$ 17419
Depreciation average rate	6.70%	6.70%
Accumulated amortization	R$ 14482	R$ 13813
Other property, plant and equipment [member]
IfrsStatementLineItems [Line Items]
Cost	11,982	7,618
Net	R$ 11741	R$ 7287
Depreciation average rate	5.00%	4.90%
Accumulated amortization	R$ 241	R$ 331

Schedule of changes in property

Schedule of changes in property, plant, and equipment (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	R$ 291157	R$ 268251	R$ 314393
Additions	50,281	42,407	78,159
Transfers	(2,782)	(57,457)	2,830
Write-offs and disposals	(576)	277	(593)
Property, plant, and equipment, beginning	268,251	314,393	267,612
Depreciation	(24,017)	(30,815)	(33,615)
Property, plant, and equipment, ending	291,157	268,251	314,393
Write-offs and disposals	576	(277)	593
Terrenos [Member]
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	94,213	94,213	92,962
Additions
Transfers		1,251	(17)
Write-offs and disposals
Property, plant, and equipment, beginning	94,213	92,962	92,979
Property, plant, and equipment, ending	94,213	94,213	92,962
Write-offs and disposals
Edificacoes [Member]
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	45,498	45,347	41,705
Additions	3,181	5,430	3,497
Transfers	(1,965)	(713)	15
Write-offs and disposals	(5)
Property, plant, and equipment, beginning	45,347	41,705	40,125
Depreciation	(1,060)	(1,075)	(1,932)
Property, plant, and equipment, ending	45,498	45,347	41,705
Write-offs and disposals	5
Equipamentos [Member]
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	115,154	101,016	152,273
Additions	38,807	26,055	63,216
Transfers	(3,398)	(49,188)	3,149
Write-offs and disposals	(365)	174	(429)
Property, plant, and equipment, beginning	101,016	152,273	116,086
Depreciation	(20,906)	(27,950)	(29,749)
Property, plant, and equipment, ending	115,154	101,016	152,273
Write-offs and disposals	365	(174)	429
Equipamentos De Transporte [Member]
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	2,472	2,969	1,984
Additions	97	298	308
Transfers	69	1,351	(1,117)
Write-offs and disposals			(2)
Property, plant, and equipment, beginning	2,969	1,984	3,473
Depreciation	(663)	(664)	(678)
Property, plant, and equipment, ending	2,472	2,969	1,984
Write-offs and disposals			2
Moveis E Utensilios [Member]
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	22,079	17,419	18,219
Additions	4,477	4,087	5,266
Transfers	1,647	(3,712)	734
Write-offs and disposals	(206)	103	(162)
Property, plant, and equipment, beginning	17,419	18,219	13,578
Depreciation	(1,258)	(1,072)	(1,197)
Property, plant, and equipment, ending	22,079	17,419	18,219
Write-offs and disposals	206	(103)	162
Outros [Member]
IfrsStatementLineItems [Line Items]
Property, plant, and equipment, ending	11,741	7,287	7,250
Additions	3,719	6,537	5,872
Transfers	865	(6,446)	66
Write-offs and disposals
Property, plant, and equipment, beginning	7,287	7,250	1,371
Depreciation	(130)	(54)	(59)
Property, plant, and equipment, ending	11,741	7,287	7,250
Write-offs and disposals

Schedule of borrowings and fina

Schedule of borrowings and financing outstanding (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Current	R$ 1830617	R$ 3034449
Noncurrent	15,893,219	14,224,175
Total	17,723,836	17,258,624	R$ 13244709	R$ 13152796
Local currency
IfrsStatementLineItems [Line Items]
Current	1,471,500	2,674,805
Noncurrent	12,956,183	11,035,957
Total	14,427,683	13,710,762	6,885,911	6,483,387
Local currency | Twelfth Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Current	45,450	45,450
Noncurrent	113,049	158,425
Total	158,499	203,875
Local currency | 14th issue debentures
IfrsStatementLineItems [Line Items]
Current	25,388	51,873
Noncurrent	0	24,205
Total	25,388	76,078
Local currency | 17th issue debentures
IfrsStatementLineItems [Line Items]
Current	102,252	91,850
Noncurrent	101,982	183,335
Total	204,234	275,185
Local currency | 18th issue debentures
IfrsStatementLineItems [Line Items]
Current	48,479	45,918
Noncurrent	92,677	135,105
Total	141,156	181,023
Local currency | 21th issue debentures
IfrsStatementLineItems [Line Items]
Current	174,849	175,000
Noncurrent	0	174,769
Total	174,849	349,769
Local currency | 22th issue debentures
IfrsStatementLineItems [Line Items]
Current	200,000	99,969
Noncurrent	508,530	678,149
Total	708,530	778,118
Local currency | 23th issue debentures
IfrsStatementLineItems [Line Items]
Current	0	0
Noncurrent	864,776	864,678
Total	864,776	864,678
Local currency | 24th issue debentures
IfrsStatementLineItems [Line Items]
Current	0	0
Noncurrent	461,350	414,994
Total	461,350	414,994
Local currency | Contractual obligations - expenses
IfrsStatementLineItems [Line Items]
Current	0	1,442,610
Noncurrent	0	0
Total	0	1,442,610
Local currency | Summary of restricted cash [Line Items]
IfrsStatementLineItems [Line Items]
Current	0	0
Noncurrent	1,168,317	1,047,767
Total	1,168,317	1,047,767
Local currency | Performance agreements
IfrsStatementLineItems [Line Items]
Current	0	0
Noncurrent	997,433	997,000
Total	997,433	997,000
Local currency | Twenty Eight Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Current	0	0
Noncurrent	1,197,395	0
Total	1,197,395	0
Local currency | Twenty Nine Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Current	0	0
Noncurrent	1,230,602	0
Total	1,230,602	0
Local currency | BrazilianFederalSavingsBankMember
IfrsStatementLineItems [Line Items]
Current	98,784	90,382
Noncurrent	1,380,170	1,324,459
Total	1,478,954	1,414,841	1,429,250	1,345,684
Local currency | Brazilian Development Bank - BNDES PAC
IfrsStatementLineItems [Line Items]
Current	13,394	13,185
Noncurrent	6,665	20,247
Total	20,059	33,432
Local currency | Brazilian Development Bank - BNDES PAC II 9751
IfrsStatementLineItems [Line Items]
Current	7,161	7,159
Noncurrent	30,308	37,447
Total	37,469	44,606
Local currency | Brazilian Development Bank - BNDES PAC II 9752
IfrsStatementLineItems [Line Items]
Current	4,851	4,851
Noncurrent	20,619	25,470
Total	25,470	30,321
Local currency | Brazilian Development Bank - BNDES ONDA LIMPA
IfrsStatementLineItems [Line Items]
Current	26,751	26,751
Noncurrent	60,089	86,809
Total	86,840	113,560
Local currency | Brazilian Development Bank - BNDES TIET? III
IfrsStatementLineItems [Line Items]
Current	33,558	86,823
Noncurrent	617,251	542,519
Total	734,844	629,342
Local currency | Brazilian Development Bank B N D E S T 2015 [Member]
IfrsStatementLineItems [Line Items]
Current	33,558	33,558
Noncurrent	420,685	454,126
Total	454,243	487,684
Local currency | Brazilian Development Bank - BNDES 2014
IfrsStatementLineItems [Line Items]
Current	6,524	5,143
Noncurrent	22,874	23,017
Total	29,398	28,160
Local currency | Inter-American Development Bank - BID 2202
IfrsStatementLineItems [Line Items]
Current	181,349	181,349
Noncurrent	2,344,403	2,524,798
Total	2,525,752	2,706,147
Local currency | Profit for the year - change in the equity
IfrsStatementLineItems [Line Items]
Current	34,800	44,815
Noncurrent	890,400	898,060
Total	925,200	942,875
Local currency | Leases (Concession Agreements, Program Contracts and Contract Assets)
IfrsStatementLineItems [Line Items]
Current	36,640	28,847
Noncurrent	360,671	399,896
Total	397,311	428,743	459,671	568,666
Local currency | Leases (Others)
IfrsStatementLineItems [Line Items]
Current	69,306	36,576
Noncurrent	56,663	9,300
Total	125,969	45,876	74,453
Local currency | Others [Member]
IfrsStatementLineItems [Line Items]
Current	4,790	3,778
Noncurrent	9,274	11,382
Total	14,064	15,160
Local currency | Interest and charges
IfrsStatementLineItems [Line Items]
Current	239,581	158,918
Noncurrent	0	0
Total	239,581	158,918
Foreign currency
IfrsStatementLineItems [Line Items]
Current	359,117	359,644
Noncurrent	2,937,036	3,188,218
Total	3,296,153	3,547,862	R$ 6358798	R$ 6669409
Foreign currency | Interest and charges
IfrsStatementLineItems [Line Items]
Current	18,091	21,577
Noncurrent	0	0
Total	18,091	21,577
Foreign currency | Inter-American Development Bank - BID 1212
IfrsStatementLineItems [Line Items]
Current	57,357	53,412
Noncurrent	172,071	213,649
Total	229,428	267,061
Foreign currency | Inter American Development Bank B I D 12121 [Member]
IfrsStatementLineItems [Line Items]
Current	0
Noncurrent	155,192	46,474
Total	155,192	46,474
Foreign currency | International Bank of Reconstruction and Development - BIRD
IfrsStatementLineItems [Line Items]
Current	33,927	31,594
Noncurrent	386,328	393,949
Total	420,255	425,543
Foreign currency | JICA 15
IfrsStatementLineItems [Line Items]
Current	55,858	58,117
Noncurrent	391,008	464,936
Total	446,866	523,053
Foreign currency | J I C A 18 [Member]
IfrsStatementLineItems [Line Items]
Current	50,223	52,253
Noncurrent	351,398	417,846
Total	401,621	470,099
Foreign currency | JICA 17
IfrsStatementLineItems [Line Items]
Current	12,833	11,260
Noncurrent	165,900	156,738
Total	178,733	167,998
Foreign currency | JICA 19
IfrsStatementLineItems [Line Items]
Current	87,901	91,456
Noncurrent	1,272,803	1,415,683
Total	1,360,704	1,507,139
Foreign currency | B I D 1983 A B 2 [Member]
IfrsStatementLineItems [Line Items]
Current	42,927	39,975
Noncurrent	42,336	78,943
Total	R$ 85263	R$ 118918

Intangible assets (Details Narr

Intangible assets (Details Narrative) R$ in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)		Dec. 31, 2020BRL (R$)Municipalities	Dec. 31, 2019BRL (R$)Municipalities	Dec. 31, 2018BRL (R$)
IfrsStatementLineItems [Line Items]
Program contracts commitments, current	R$ 77652		R$ 162541
Program contracts commitments, noncurrent	R$ 44995		R$ 68939
Percentage of revenue	4445.00%		4458.00%
Intangible assets related to PPP ALTO TIETE	R$ 269062		R$ 287645
Monthly remuneration plus any interests and charges	36,519
Intangible assets related to PPP Sao Lourenco	R$ 2895798		R$ 3065445
Intangible assets, discount rate for adjustment - PPP	7.80%
Amortization average rate	4.90%		4.70%	4.20%
Rights of use were written off	R$ 108406
Minimum performance percentage is not reached	12000.00%
Contract asset	R$ 8550102	[1]	R$ 7969164	R$ 7617714	R$ 7407948
Intangible assets	36,503,834		34,405,575	R$ 32325447	R$ 29012460
Performance Agreements [Member]
IfrsStatementLineItems [Line Items]
Contract asset	737,657		306,738
Intangible assets	R$ 871488		R$ 265940
Sao Paulo [Member]
IfrsStatementLineItems [Line Items]
Number of municipalities | Municipalities			375	372
Percentage of revenue	7.50%
[1]	The largest works are located in the municipalities of São Paulo, Praia Grande and São Bernardo do Campo, in the amounts of R$ 3,955 million, R$ 634 million and R$ 407 million, respectively.

Schedule of borrowings terms (D

Schedule of borrowings terms (Details)	12 Months Ended
	Dec. 31, 2021
Local currency | Twelfth [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2025
Annual interest rates	TR + 9.5%
Local currency | 14th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2022
Annual interest rates	TJLP +1.92% (Series 1 and 3) and 9.19% (Series 2)
Inflation adjustment	IPCA (Series 2)
Local currency | 17th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2023
Annual interest rates	CDI +0.75% (Series 1) and 4.5% (Series 2) and 4.75% (Series 3)
Inflation adjustment	IPCA (Series 2 and 3)
Local currency | 18th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2024
Annual interest rates	TJLP + 1.92 % (Series 1 and 3) and 8.25% (Series 2)
Inflation adjustment	IPCA (Series 2)
Local currency | 21th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2022
Annual interest rates	CDI + 0.60% e CDI+ 0.90%
Local currency | 22th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2025
Annual interest rates	CDI +0.58% (Series 1) and CDI + 0.90% (Series 2) and 6.0% (Series 3)
Inflation adjustment	IPCA (Series 3)
Local currency | 23th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2027
Annual interest rates	CDI +0.49% (Series 1) and CDI + 0.63% (Series 2)
Local currency | 24th issue debentures
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2029
Annual interest rates	3.20% (Series 1) and 3.37% (Series 2)
Inflation adjustment	IPCA (Series 1 and 2)
Local currency | Contractual obligations - expenses
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2021
Annual interest rates	CDI + 3.3%
Local currency | Twenty Sixth Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2030
Annual interest rates	4.65% (series 1) and 4.95% (series 2)
Inflation adjustment	IPCA (series 1 and 2)
Local currency | Twenty Seventh Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2027
Annual interest rates	CDI +1.60% (Series 1) and CDI + 1.80% (Series 2) and 2.25% (Series 3)
Local currency | Twenty Eight Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2028
Annual interest rates	CDI +1.20% (Series 1) and CDI + 1.44% (Series 2) and 1.60% (Series 3)
Local currency | Twenty Nine Issue Debentures [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2036
Annual interest rates	CDI +1.29% (Series 1) and 5.3058% (Series 2) and 5.4478% (Series 3)
Inflation adjustment	IPCA (series 2 and 3)
Local currency | BrazilianFederalSavingsBankMember
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2021/2042
Annual interest rates	5% to 9.5%
Inflation adjustment	TR
Local currency | Brazilian Development Bank - BNDES PAC
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2023
Annual interest rates	TJLP+1.82%
Local currency | Brazilian Development Bank - BNDES PAC II 9751
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2027
Annual interest rates	TJLP+1.72%
Local currency | Brazilian Development Bank - BNDES PAC II 9752
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2027
Annual interest rates	TJLP+1.72%
Local currency | Brazilian Development Bank - BNDES ONDA LIMPA
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2025
Annual interest rates	TJLP+1.92%
Local currency | Brazilian Development Bank - BNDES TIET? III
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2028
Annual interest rates	TJLP+1.66%
Local currency | Brazilian Development Bank B N D E S 2015 [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2035
Annual interest rates	TJLP+2.18%
Local currency | Brazilian Development Bank - BNDES 2014
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2026
Annual interest rates	TJLP+1.76%
Local currency | Leases (Concession Agreements, Program Contracts and Contract Assets)
IfrsStatementLineItems [Line Items]
Inflation adjustment	IPC
Local currency | Others [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2025
Annual interest rates	3% (FEHIDRO) and TJLP + 1.5% (FINEP)
Foreign currency | Inter-American Development Bank - BID 2202
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2035
Annual interest rates	CDI+0.86%
Foreign currency | Profit for the year - change in the equity
IfrsStatementLineItems [Line Items]
Guarantees	Own funds
Maturity	2034
Annual interest rates	CDI+1.90% and CDI+2.70%
Foreign currency | Leases (Concession Agreements, Program Contracts and Contract Assets)
IfrsStatementLineItems [Line Items]
Maturity	2035
Annual interest rates	7.73% to 10.12%
Foreign currency | Other Leases [Member]
IfrsStatementLineItems [Line Items]
Maturity	2023
Annual interest rates	4.25% to 12.34%
Foreign currency | Inter-American Development Bank - BID 1212
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2025
Annual interest rates	3.31% (*)
Exchange rate changes	US$
Foreign currency | Inter American Development Bank B I D 4623 [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2044
Annual interest rates	1.12% (*)
Exchange rate changes	US$
Foreign currency | International Bank For Reconstruction And Development [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2034
Annual interest rates	2.85% (*)
Foreign currency | JICA 15
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2029
Annual interest rates	1.8% and 2.5%
Exchange rate changes	Yen
Foreign currency | J I C A 18 [Member]
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2029
Annual interest rates	1.8% and 2.5%
Exchange rate changes	Yen
Foreign currency | JICA 17
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2035
Annual interest rates	1.2% and 0.01%
Exchange rate changes	Yen
Foreign currency | JICA 19
IfrsStatementLineItems [Line Items]
Guarantees	Government
Maturity	2037
Annual interest rates	1.7% and 0.01%
Exchange rate changes	Yen
Foreign currency | B I D 1983 A B U S 15385 Thousand [Member]
IfrsStatementLineItems [Line Items]
Guarantees	-
Maturity	2023
Annual interest rates	2.08% to 2.38% (*)
Exchange rate changes	US$

Schedule of borrowings payment

Schedule of borrowings payment schedule (Details) R$ in Thousands	Dec. 31, 2021BRL (R$)
IfrsStatementLineItems [Line Items]
2022	R$ 1830617
2023	1,635,034
2024	1,923,571
2025	2,050,193
2026	1,915,508
2027	1,989,822
2028 to 2044	6,379,091
TOTAL	17,723,836
Local currency
IfrsStatementLineItems [Line Items]
2022	1,471,500
2023	1,294,598
2024	1,625,471
2025	1,747,639
2026	1,665,857
2027	1,740,171
2028 to 2044	4,882,447
TOTAL	14,427,683
Local currency | Debentures
IfrsStatementLineItems [Line Items]
2022	596,418
2023	694,806
2024	1,062,558
2025	1,194,424
2026	1,074,178
2027	1,153,648
2028 to 2044	1,556,497
TOTAL	7,332,529
Local currency | BrazilianFederalSavingsBankMember
IfrsStatementLineItems [Line Items]
2022	98,784
2023	94,055
2024	93,315
2025	99,152
2026	105,355
2027	111,936
2028 to 2044	876,357
TOTAL	1,478,954
Local currency | BNDES
IfrsStatementLineItems [Line Items]
2022	209,832
2023	203,103
2024	196,438
2025	176,274
2026	166,466
2027	154,029
2028 to 2044	282,181
TOTAL	1,388,323
Local currency | SummaryOfCashAndCashEquivalentsTableTextBlock
IfrsStatementLineItems [Line Items]
2022	181,349
2023	181,349
2024	181,349
2025	181,349
2026	181,349
2027	181,349
2028 to 2044	1,437,658
TOTAL	2,525,752
Local currency | B I D I N V E S T [Member]
IfrsStatementLineItems [Line Items]
2022	34,800
2023	37,340
2024	39,550
2025	44,300
2026	106,390
2027	108,728
2028 to 2044	554,092
TOTAL	925,200
Local currency | Leases (Concession Agreements, Program Contracts and Contract Assets)
IfrsStatementLineItems [Line Items]
2022	36,640
2023	39,132
2024	40,228
2025	44,322
2026	30,846
2027	30,481
2028 to 2044	175,662
TOTAL	397,311
Local currency | Leases (Others)
IfrsStatementLineItems [Line Items]
2022	69,306
2023	40,094
2024	9,640
2025	5,656
2026	1,273
2027	0
2028 to 2044	0
TOTAL	125,969
Local currency | OtherBorrowingsMember
IfrsStatementLineItems [Line Items]
2022	4,790
2023	4,719
2024	2,393
2025	2,162
2026	0
2027	0
2028 to 2044	0
TOTAL	14,064
Local currency | BorrowingsInterestAndChargesMember
IfrsStatementLineItems [Line Items]
2022	239,581
2023	0
2024	0
2025	0
2026	0
2027	0
2028 to 2044	0
TOTAL	239,581
Foreign currency
IfrsStatementLineItems [Line Items]
2022	359,117
2023	340,436
2024	298,100
2025	302,554
2026	249,651
2027	249,651
2028 to 2044	1,496,644
TOTAL	3,296,153
Foreign currency | BorrowingsInterestAndChargesMember
IfrsStatementLineItems [Line Items]
2022	18,091
2023	0
2024	0
2025	0
2026	0
2027	0
2028 to 2044	0
TOTAL	18,091
Foreign currency | BID
IfrsStatementLineItems [Line Items]
2022	57,357
2023	57,357
2024	57,357
2025	61,811
2026	8,908
2027	8,908
2028 to 2044	132,922
TOTAL	384,620
Foreign currency | BIRD
IfrsStatementLineItems [Line Items]
2022	33,927
2023	33,928
2024	33,928
2025	33,928
2026	33,928
2027	33,928
2028 to 2044	216,688
TOTAL	420,255
Foreign currency | JICA
IfrsStatementLineItems [Line Items]
2022	206,815
2023	206,815
2024	206,815
2025	206,815
2026	206,815
2027	206,815
2028 to 2044	1,147,034
TOTAL	2,387,924
Foreign currency | BID 1983AB
IfrsStatementLineItems [Line Items]
2022	42,927
2023	42,336
2024	0
2025	0
2026	0
2027	0
2028 to 2044	0
TOTAL	R$ 85263

Schedule of changes in borrowin

Schedule of changes in borrowings (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	R$ 17258624	R$ 13244709	R$ 13152796
Addition (lease)	140,187	28,549
Funding	2,959,633	4,845,860	1,808,587
Borrowing costs	(36,822)	(68,386)	(15,199)
Monetary variation and exchange rate changes	177,269	2,267,179	280,526
Inflation adjustment / exchange variation and incorporated interest - Capitalized	10,198	67,304	59,306
Interest paid	(845,445)	(626,625)	(737,326)
Amortization	2,896,604	3,244,099	2,148,198
Accrued interest	647,980	559,931	568,679
Provision for interest and fees - Capitalized	290,594	171,026	153,177
Expenses with borrowing costs	18,222	13,176
Borrowings and financing, ending	17,723,836	17,258,624	13,244,709
Amortization	(2,896,604)	(3,244,099)	(2,148,198)
Foreign/local currency translation
Addition as per IFRS 16			113,233
Amortization of borrowing costs			9,128
Local currency
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	13,710,762	6,885,911	6,483,387
Addition (lease)	140,187	28,549
Funding	2,816,545	4,752,889	1,688,186
Borrowing costs	(25,749)	(59,453)	(12,442)
Monetary variation and exchange rate changes	225,791	86,939	46,567
Inflation adjustment / exchange variation and incorporated interest - Capitalized			4,587
Interest paid	(788,587)	(419,082)	(476,313)
Amortization	(2,553,645)	(919,040)	(1,433,962)
Accrued interest	601,187	406,826	385,470
Provision for interest and fees - Capitalized	284,015	128,869	83,119
Expenses with borrowing costs	17,177	10,983
Borrowings and financing, ending	14,427,683	13,710,762	6,885,911
Amortization	2,553,645	919,040	1,433,962
Foreign/local currency translation		2,807,371
Addition as per IFRS 16			113,233
Amortization of borrowing costs			4,079
Local currency | Debentures
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	6,756,504	3,711,228	3,486,861
Addition (lease)
Funding	2,450,000	3,507,640	1,266,755
Borrowing costs	(25,717)	(52,328)	(11,814)
Monetary variation and exchange rate changes	225,106	86,939	42,692
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid	(387,618)	(161,494)	(234,307)
Amortization	(1,963,282)	(572,871)	(1,055,623)
Accrued interest	258,114	201,150	195,586
Provision for interest and fees - Capitalized	139,563	26,073	17,233
Expenses with borrowing costs	15,298	10,167
Borrowings and financing, ending	7,467,968	6,756,504	3,711,228
Amortization	1,963,282	572,871	1,055,623
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs			3,845
Local currency | BrazilianFederalSavingsBankMember
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	1,414,841	1,429,250	1,345,684
Addition (lease)
Funding	156,488	74,485	162,767
Borrowing costs
Monetary variation and exchange rate changes	685
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid	(113,030)	(111,601)	(109,128)
Amortization	(93,064)	(84,821)	(79,404)
Accrued interest	79,966	73,067	74,421
Provision for interest and fees - Capitalized	33,236	38,452	34,910
Expenses with borrowing costs
Borrowings and financing, ending	1,478,954	1,414,841	1,429,250
Amortization	93,064	84,821	79,404
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs
Local currency | BNDES
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	1,370,902	1,201,411	1,072,605
Addition (lease)
Funding	207,136	213,514	256,981
Borrowing costs			(628)
Monetary variation and exchange rate changes			2,082
Inflation adjustment / exchange variation and incorporated interest - Capitalized			826
Interest paid	(88,084)	(47,164)	(83,419)
Amortization	(186,179)	(81,213)	(131,026)
Accrued interest	51,122	47,668	60,644
Provision for interest and fees - Capitalized	37,688	36,427	23,112
Expenses with borrowing costs	259	259
Borrowings and financing, ending	1,392,844	1,370,902	1,201,411
Amortization	186,179	81,213	131,026
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs			234
Local currency | SummaryOfCashAndCashEquivalentsTableTextBlock
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	2,730,195
Addition (lease)
Funding
Borrowing costs
Monetary variation and exchange rate changes
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid	(97,829)	(37,613)
Amortization	(181,349)	(90,674)
Accrued interest	63,964	22,668
Provision for interest and fees - Capitalized	73,506	27,886
Expenses with borrowing costs	955	557
Borrowings and financing, ending	2,589,442	2,730,195
Amortization	181,349	90,674
Foreign/local currency translation		2,807,371
Local currency | B I D I N V E S T [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	944,513
Addition (lease)
Funding		950,000
Borrowing costs		(7,125)
Monetary variation and exchange rate changes
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid	(33,276)
Amortization	(18,340)
Accrued interest	63,380	1,638
Provision for interest and fees - Capitalized
Expenses with borrowing costs	665
Borrowings and financing, ending	956,942	944,513
Amortization	18,340
Foreign/local currency translation
Local currency | Leases (Concession Agreements, Program Contracts and Contract Assets)
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	428,743	459,671	568,666
Addition (lease)
Funding
Borrowing costs
Monetary variation and exchange rate changes			1,765
Inflation adjustment / exchange variation and incorporated interest - Capitalized			3,761
Interest paid	(52,250)	(51,431)	(47,663)
Amortization	(31,432)	(30,928)	(123,880)
Accrued interest	52,250	51,431	49,160
Provision for interest and fees - Capitalized			7,862
Expenses with borrowing costs
Borrowings and financing, ending	397,311	428,743	459,671
Amortization	31,432	30,928	123,880
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs
Local currency | Leases (Others)
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	45,876	74,453
Addition (lease)	140,187	28,549
Funding
Borrowing costs
Monetary variation and exchange rate changes
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid	(15,782)	(9,108)	(1,141)
Amortization	(76,013)	(56,571)	(42,646)
Accrued interest	31,701	8,553	5,007
Provision for interest and fees - Capitalized
Expenses with borrowing costs
Borrowings and financing, ending	125,969	45,876	74,453
Amortization	76,013	56,571	42,646
Foreign/local currency translation
Addition as per IFRS 16			113,233
Amortization of borrowing costs
Local currency | OtherBorrowingsMember
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	15,197	9,898	9,571
Addition (lease)
Funding	2,921	7,250	1,683
Borrowing costs	(32)
Monetary variation and exchange rate changes			28
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid	(718)	(671)	(655)
Amortization	(3,986)	(1,962)	(1,383)
Accrued interest	690	651	652
Provision for interest and fees - Capitalized	22	31	2
Expenses with borrowing costs
Borrowings and financing, ending	14,094	15,197	9,898
Amortization	3,986	1,962	1,383
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs
Foreign currency
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	3,547,862	6,358,798	6,669,409
Addition (lease)
Funding		92,971	120,401
Borrowing costs		(8,933)	(2,757)
Monetary variation and exchange rate changes		2,180,240	233,959
Inflation adjustment / exchange variation and incorporated interest - Capitalized		67,304	54,719
Interest paid		(207,543)	(261,013)
Amortization		(2,325,059)	(714,236)
Accrued interest		153,105	183,209
Provision for interest and fees - Capitalized		42,157	70,058
Expenses with borrowing costs		2,193
Borrowings and financing, ending	3,296,153	3,547,862	6,358,798
Amortization		2,325,059	714,236
Foreign/local currency translation		(2,807,371)
Addition as per IFRS 16
Amortization of borrowing costs			5,049
Foreign currency | BID
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	317,302	2,316,190	2,399,985
Addition (lease)
Funding	108,728	52,141
Borrowing costs	(7,620)	(6,635)
Monetary variation and exchange rate changes	22,979	845,246	40,594
Inflation adjustment / exchange variation and incorporated interest - Capitalized		48,246	49,387
Interest paid	(8,488)	(45,010)	(83,602)
Amortization	(53,197)	(121,088)	(171,892)
Accrued interest	7,936	10,490	26,332
Provision for interest and fees - Capitalized		24,695	54,431
Expenses with borrowing costs	197	398
Borrowings and financing, ending	387,837	317,302	2,316,190
Amortization	53,197	121,088	171,892
Foreign/local currency translation		(2,807,371)
Addition as per IFRS 16
Amortization of borrowing costs			955
Foreign currency | BIRD
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	426,860	357,880	356,420
Addition (lease)
Funding			2,540
Borrowing costs	(3,377)	(2,029)	(2,540)
Monetary variation and exchange rate changes	30,814	102,029	12,575
Inflation adjustment / exchange variation and incorporated interest - Capitalized		1,217	1,657
Interest paid	(2,481)	(7,572)	(10,627)
Amortization	(32,965)	(31,216)	(12,273)
Accrued interest	1,789	5,659	8,548
Provision for interest and fees - Capitalized		752	1,561
Expenses with borrowing costs	241	140
Borrowings and financing, ending	420,881	426,860	357,880
Amortization	32,965	31,216	12,273
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs			19
Foreign currency | Eurobonds [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	2,684,321	1,413,956	1,358,412
Addition (lease)
Funding	34,360
Borrowing costs	(76)
Monetary variation and exchange rate changes	(108,851)	457,931	54,565
Inflation adjustment / exchange variation and incorporated interest - Capitalized	10,198
Interest paid	(43,184)	(104,170)	(102,883)
Amortization	(216,190)	(1,868,676)
Accrued interest	35,315	90,941	94,095
Provision for interest and fees - Capitalized	5,802	9,195	8,943
Expenses with borrowing costs	192	823
Borrowings and financing, ending	2,401,887	2,684,321	1,413,956
Amortization	216,190	1,868,676
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs			824
Foreign currency | JICA
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	119,379	2,106,908	2,036,128
Addition (lease)
Funding		40,830	117,861
Borrowing costs		(117)	(112)
Monetary variation and exchange rate changes	6,536	715,956	104,027
Inflation adjustment / exchange variation and incorporated interest - Capitalized		17,841	3,675
Interest paid	(2,705)	(43,758)	(35,001)
Amortization	(40,607)	(200,597)	(155,064)
Accrued interest	1,753	40,172	32,194
Provision for interest and fees - Capitalized	777	6,897	3,013
Expenses with borrowing costs	415	189
Borrowings and financing, ending	85,548	119,379	2,106,908
Amortization	40,607	200,597	155,064
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs			187
Foreign currency | B I D 1983 A B 1 [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	1,507,139
Funding	143,088
Borrowing costs	(11,073)
Monetary variation and exchange rate changes	(48,522)
Inflation adjustment / exchange variation and incorporated interest - Capitalized		10,198
Interest paid	(56,858)
Amortization	(342,959)
Accrued interest	46,793
Provision for interest and fees - Capitalized	6,579
Expenses with borrowing costs	1,045
Borrowings and financing, ending	3,296,153	1,507,139
Amortization	342,959
Foreign currency | BID 1983AB
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning	1,507,139	163,864	225,592
Addition (lease)
Funding
Borrowing costs		(152)	(105)
Monetary variation and exchange rate changes		59,078	8,943
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid		(7,033)	(10,338)
Amortization		(103,482)	(71,141)
Accrued interest		5,843	9,111
Provision for interest and fees - Capitalized		618	870
Expenses with borrowing costs		643
Borrowings and financing, ending		1,507,139	163,864
Amortization		103,482	71,141
Foreign/local currency translation
Addition as per IFRS 16
Amortization of borrowing costs			932
Foreign currency | Deutsche Bank [Member]
IfrsStatementLineItems [Line Items]
Borrowings and financing, beginning			292,872
Funding
Borrowing costs
Monetary variation and exchange rate changes			13,255
Inflation adjustment / exchange variation and incorporated interest - Capitalized
Interest paid			(18,562)
Amortization			(303,866)
Accrued interest			12,929
Provision for interest and fees - Capitalized			1,240
Borrowings and financing, ending
Amortization			303,866
Addition as per IFRS 16
Amortization of borrowing costs			R$ 2132

Schedule of funding (Details)

Schedule of funding (Details) - BRL (R$)	1 Months Ended	12 Months Ended
	Jul. 30, 2021	Dec. 31, 2021
Twenty Eighth Issue Debentures Series One [Member]
IfrsStatementLineItems [Line Items]
Amount	R$ 1200000000	R$ 127800000
Maturity		07/2024
Remuneration		CDI + 1.20 p.a.
Twenty Eighth Issue Debentures Series Two [Member]
IfrsStatementLineItems [Line Items]
Amount		R$ 888200000
Maturity		07/2026
Remuneration		CDI + 1.44 p.a.
Twenty Eighth Issue Debentures Series Three [Member]
IfrsStatementLineItems [Line Items]
Amount		R$ 184000000
Maturity		07/2028
Remuneration		CDI + 1.60 p.a.
Twenty Nine Issue Debentures Series One [Member]
IfrsStatementLineItems [Line Items]
Amount		R$ 500000000
Maturity		12/2026
Remuneration		CDI + 1.29% p.a.
Twenty Nine Issue Debentures Series Two [Member]
IfrsStatementLineItems [Line Items]
Amount		R$ 600000000
Maturity		12/2031
Remuneration		IPCA + 5.3058% p.a.
Twenty Nine Issue Debentures Series Three [Member]
IfrsStatementLineItems [Line Items]
Amount		R$ 150000000
Maturity		12/2036
Remuneration		IPCA + 5.4478% p.a.

Schedule of restrictive covenan

Schedule of restrictive covenants ratios (Details)	12 Months Ended
	Dec. 31, 2020
Adjusted EBITDA / Adjusted financial expenses
IfrsStatementLineItems [Line Items]
Restrictive ratios	Equal to or higher than 2.80
Adjusted net debt / Adjusted EBITDA
IfrsStatementLineItems [Line Items]
Restrictive ratios	Equal to or higher than 2.35
Adjusted total debt / Adjusted EBITDA
IfrsStatementLineItems [Line Items]
Restrictive ratios	Equal to or lower than 3.80
Other onerous debt / Adjusted EBITDA
IfrsStatementLineItems [Line Items]
Restrictive ratios	Equal to or lower than 3.50
Adjusted current ratio
IfrsStatementLineItems [Line Items]
Restrictive ratios	Lower than 3.65
EBITDA / Paid financial expenses
IfrsStatementLineItems [Line Items]
Restrictive ratios	Equal to or lower than 1.30
Net debt / Adjusted EBITDA
IfrsStatementLineItems [Line Items]
Restrictive ratios	Higher than 1.00

Schedule of borrowings and fi_2

Schedule of borrowings and financing - Credit Limits (Details) R$ in Thousands	Dec. 31, 2021BRL (R$)Number	Dec. 31, 2020Number
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	R$ 4769
United States of America, Dollars
IfrsStatementLineItems [Line Items]
Exchange rate | Number	5.5805
Japan, Yen
IfrsStatementLineItems [Line Items]
Exchange rate | Number	0.04847	0.05043
BrazilianFederalSavingsBankMember
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	R$ 1353
Plan assets
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	455
Accumulated amortization
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	48
CapitalIncrease2
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	1,505
SummaryOfIntangibleAssetsTable [Table]
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	1,392
Inflation adjustment
IfrsStatementLineItems [Line Items]
Borrowings and financing - credit limits	R$ 16

Current assets (Details)

Current assets (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Current tax assets	R$ 276104	R$ 22672
Income Tax And Socials Contribution [Member]
IfrsStatementLineItems [Line Items]
Current tax assets	259,902	0
Withholdings Income Tax [Member]
IfrsStatementLineItems [Line Items]
Current tax assets	13,041	4,391
Other Federal Taxes [Member]
IfrsStatementLineItems [Line Items]
Current tax assets	R$ 3161	R$ 18281

Current liabilities (Details)

Current liabilities (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Current tax liabilities	R$ 257130	R$ 266819
Income Tax And Social Contribution [Member]
IfrsStatementLineItems [Line Items]
Current tax liabilities		69,041
C O F I N S And Pasep [Member]
IfrsStatementLineItems [Line Items]
Current tax liabilities	111,963	93,601
Social Securitys Contribution [Member]
IfrsStatementLineItems [Line Items]
Current tax liabilities	39,902	37,599
I R R F Withholding Income Tax On Financials Investments [Member]
IfrsStatementLineItems [Line Items]
Current tax liabilities	49,468	21,287
Other Tax Payables [Member]
IfrsStatementLineItems [Line Items]
Current tax liabilities	R$ 55797	R$ 45291

Schedule of deferred taxes (Det

Schedule of deferred taxes (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Total deferred tax assets	R$ 1012595	R$ 931736	R$ 905258	R$ 933815
Total deferred tax liabilities	(1,296,334)	(1,252,452)	(1,339,254)	(1,195,057)
Deferred tax assets (liabilities), net	(283,739)	(320,716)	(433,996)	(261,242)
Tax Provisions [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax assets	503,374	436,445	366,673	337,833
Pension Obligations G 1 [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax assets	150,577	154,498	157,998	157,044
Donations [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax assets	47,589	50,142	51,818	54,131
Credit Losses [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax assets	183,963	155,719	145,622	197,920
Deferred Taxes Other [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax assets	127,092	134,932	183,147	186,887
Temporary differences [member]
IfrsStatementLineItems [Line Items]
Total deferred tax liabilities	(368,235)	(388,675)	(408,732)	(433,842)
Capitalization Borrowing Costs [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax liabilities	(404,931)	(390,211)	(409,236)	(420,978)
Profit On Supply Government Entities [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax liabilities	(353,262)	(356,513)	(372,289)	(206,978)
Actuarial Gain Loss G 1 [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax liabilities	(109,271)	(48,979)	(54,222)	(36,430)
Construction Margin [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax liabilities	(46,079)	(48,843)	(83,399)	(86,164)
Borrowing Costs [Member]
IfrsStatementLineItems [Line Items]
Total deferred tax liabilities	R$ 14556	R$ 19231	R$ 11376	R$ 10665

Schedule of realization (Detail

Schedule of realization (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Deferred income tax assets	R$ 1012595	R$ 931736	R$ 905258	R$ 933815
Deferred income tax liabilities	(1,296,334)	(1,252,452)	(1,339,254)	(1,195,057)
Deferred tax assets (liabilities), net	(283,739)	(320,716)	R$ 433996	R$ 261242
Realized Within 12 Months [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets	280,373	263,580
Deferred income tax liabilities	(31,777)	(31,388)
Realized After 1 Year [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets	732,222	668,156
Deferred income tax liabilities	R$ 1264557	R$ 1221064

Schedule of changes (Details)

Schedule of changes (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Deferred income tax assets, ending	R$ 1012595	R$ 931736	R$ 905258	R$ 933815
Deferred tax asset, changes	80,859	26,478	(28,557)
Deferred income tax liabilities	R$ 1296334	R$ 1252452	R$ 1339254	(1,195,057)
Deferred tax liabilities, changes	(43,882)	86,802	(144,197)
Deferred tax assets (liabilities) net, ending	(283,739)	(320,716)	(433,996)	(261,242)
Deferred tax assets, net, changes	36,977	113,280	(172,754)
Opening balance	(320,716)	(433,996)	(261,242)
- corresponding entry to the income statement	97,269	108,037	(154,962)
- corresponding entry to valuation adjustments to equity (Note 21 (b))	(60,292)	5,243	(17,792)
Total net change	36,977	113,280	(172,754)
Closing balance	(283,739)	(320,716)	(433,996)
Tax Provisions [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets, ending	R$ 503374	R$ 436445	R$ 366673	337,833
Deferred tax asset, changes	66,929	69,772	28,840
Pension Obligations G 1 [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets, ending	R$ 150577	R$ 154498	R$ 157998	157,044
Deferred tax asset, changes	(3,921)	(3,500)	954
Donations [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets, ending	R$ 47589	R$ 50142	R$ 51818	54,131
Deferred tax asset, changes	(2,553)	(1,676)	(2,313)
Credit Losses [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets, ending	R$ 183963	R$ 155719	R$ 145622	197,920
Deferred tax asset, changes	28,244	10,097	(52,298)
Deferred Taxes Other [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax assets, ending	R$ 127092	R$ 134932	R$ 183147	186,887
Deferred tax asset, changes	(7,840)	(48,215)	(3,740)
Temporary differences [member]
IfrsStatementLineItems [Line Items]
Deferred income tax liabilities	R$ 368235	R$ 388675	R$ 408732	(433,842)
Deferred tax liabilities, changes	20,440	20,057	25,110
Capitalization Borrowing Costs [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax liabilities	(404,931)	(390,211)	(409,236)	(420,978)
Deferred tax liabilities, changes	(14,720)	19,025	11,742
Profit On Supply Government Entities [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax liabilities	(353,262)	(356,513)	(372,289)	(206,978)
Deferred tax liabilities, changes	3,251	15,776	(165,311)
Actuarial Gain Loss G 1 [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax liabilities	(109,271)	(48,979)	(54,222)	(36,430)
Deferred tax liabilities, changes	(60,292)	5,243	(17,792)
Construction Margin [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax liabilities	(46,079)	(48,843)	(83,399)	(86,164)
Deferred tax liabilities, changes	2,764	34,556	2,765
Borrowing Costs [Member]
IfrsStatementLineItems [Line Items]
Deferred income tax liabilities	(14,556)	(19,231)	(11,376)	R$ 10665
Deferred tax liabilities, changes	R$ 4675	R$ 7855	R$ 711

Reconciliation of the effective

Reconciliation of the effective tax rate (Details) - BRL (R$) R$ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Profit before income taxes		R$ 3170156	R$ 1326002	R$ 4677942
Statutory rate		34.00%	34.00%	34.00%
Estimated expense at statutory rate		R$ 1077853	R$ 450841	R$ 1590500
Tax benefit of interest on equity		200,073	126,604	312,339
Provision – Law 4,819/1958 – G0	[1]	(22,640)	(37,675)	(44,426)
Donations		(16,723)	(8,672)	(19,888)
Other differences		52,856	17,900	32,050
Income tax and social contribution		(864,287)	(352,684)	(1,310,425)
Current income tax and social contribution		(961,556)	(460,721)	(1,155,463)
Deferred income tax and social contribution		R$ 97269	R$ 108037	R$ 154962
Effective rate		27.00%	27.00%	28.00%
[1]	Permanent difference related to the provision for actuarial liability (Note 22 (ii) and (v)).

Schedule of lawsuits and procee

Schedule of lawsuits and proceedings that resulted in provisions (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Provisions	R$ 1480510	R$ 1283662
Escrow deposits	(32,017)	(31,360)
Total	1,448,493	1,252,302
Customer Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions	168,258	160,705
Escrow deposits	(10,780)	(10,553)
Total	157,478	150,152
Supplier Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions	477,854	410,734
Escrow deposits	(123)	(358)
Total	477,731	410,376
Other Civil Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions	95,601	86,083
Escrow deposits	(2,523)	(2,505)
Total	93,078	83,578
Tax Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions	57,509	59,678
Escrow deposits	(2,693)	(2,410)
Total	54,816	57,268
Labor Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions	349,962	316,880
Escrow deposits	(15,864)	(15,503)
Total	334,098	301,377
Environmental Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions	331,326	249,582
Escrow deposits	(34)	(31)
Total	331,292	249,551
Current Provision [Member]
IfrsStatementLineItems [Line Items]
Provisions	809,821	760,209
Escrow deposits
Total	809,821	760,209
Noncurrent Provision [Member]
IfrsStatementLineItems [Line Items]
Provisions	670,689	523,453
Escrow deposits	(32,017)	(31,360)
Total	R$ 638672	R$ 492093

Schedule of changes in provisio

Schedule of changes in provisions (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
IfrsStatementLineItems [Line Items]
Provisions, ending	R$ 1448493	R$ 1252302	R$ 1035808	R$ 892862
Additional provisions	250,374	270,575	348,388
Interest and inflation adjustment	216,855	295,777	252,243
Use of the accrual	(144,847)	(214,689)	(250,280)
Amounts not used (reversal)	(126,191)	(135,169)	(207,405)
Customer Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	168,258	160,705	253,665	290,649
Additional provisions	32,996	16,465	57,314
Interest and inflation adjustment	29,685	19,638	53,929
Use of the accrual	(30,972)	(78,640)	(99,379)
Amounts not used (reversal)	(24,156)	(50,423)	(48,848)
Supplier Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	477,854	410,734	153,654	67,985
Additional provisions	92,135	149,566	54,223
Interest and inflation adjustment	90,788	201,259	102,686
Use of the accrual	(71,238)	(68,801)	(42,948)
Amounts not used (reversal)	(44,565)	(24,944)	(28,292)
Other Civil Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	95,601	86,083	93,910	98,302
Additional provisions	15,477	15,944	28,888
Interest and inflation adjustment	12,850	11,109	18,713
Use of the accrual	(10,056)	(23,009)	(9,766)
Amounts not used (reversal)	(8,753)	(11,871)	(42,227)
Tax Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	57,509	59,678	59,143	63,335
Additional provisions	8,630	4,333	11,821
Interest and inflation adjustment	8,054	2,737	2,918
Use of the accrual	(15,133)	(1,875)	(4,982)
Amounts not used (reversal)	(3,720)	(4,660)	(13,949)
Labor Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	349,962	316,880	325,129	302,935
Additional provisions	100,245	61,782	167,995
Interest and inflation adjustment	36,373	35,541	61,483
Use of the accrual	(66,220)	(61,039)	(112,084)
Amounts not used (reversal)	(37,316)	(44,533)	(95,200)
Environmental Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	331,326	249,582	192,950	170,419
Additional provisions	40,477	35,392	42,198
Interest and inflation adjustment	50,957	27,718	24,358
Use of the accrual	(33)		(312)
Amounts not used (reversal)	(9,657)	(6,478)	(43,713)
Subtotal Claim [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	1,480,510	1,283,662	1,078,451	993,625
Additional provisions	289,960	283,482	362,439
Interest and inflation adjustment	228,707	298,002	264,087
Use of the accrual	(193,652)	(233,364)	(269,471)
Amounts not used (reversal)	(128,167)	(142,909)	(272,229)
Escrow Deposit [Member]
IfrsStatementLineItems [Line Items]
Provisions, ending	(32,017)	(31,360)	(42,643)	R$ 100763
Additional provisions	(39,586)	(12,907)	(14,051)
Interest and inflation adjustment	(11,852)	(2,225)	(11,844)
Use of the accrual	48,805	18,675	19,191
Amounts not used (reversal)	R$ 1976	R$ 7740	R$ 64824

Lawsuits deemed as contingent l

Lawsuits deemed as contingent liabilities (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	R$ 8394883	R$ 10460737
Customer Claim [Member]
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	173,875	110,508
Supplier Claim [Member]
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	1,521,935	1,350,308
Other Civil Claim [Member]
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	852,735	758,800
Tax Claim [Member]
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	1,548,781	1,253,636
Labor Claim [Member]
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	1,095,841	1,005,648
Environmental Claim [Member]
IfrsStatementLineItems [Line Items]
Significant contingent liabilities	R$ 3201716	R$ 5981837

Borrowings and financing (Detai

Borrowings and financing (Details Narrative)	1 Months Ended	12 Months Ended
	Jul. 30, 2021BRL (R$)	Dec. 31, 2021BRL (R$)Number	Dec. 25, 2021BRL (R$)	Dec. 22, 2021BRL (R$)	Dec. 21, 2021BRL (R$)	Dec. 17, 2021BRL (R$)	Dec. 31, 2020Number
IfrsStatementLineItems [Line Items]
Total commission		R$ 21250
Issuer's net sales and/or service revenue, percentage		25.00%
Lease payment period		the lease payment period starts (240 monthly installments)
Increase (decrease) in the lawsuits deemed as contingent liabilities
IfrsStatementLineItems [Line Items]
Amortized installments amount		R$ 1450000000	R$ 1585900000	R$ 100000000	R$ 175000000	R$ 91700000
Amortized installments amount		135,900,000
Twenty Eighth Issue Debentures Series One [Member]
IfrsStatementLineItems [Line Items]
Amount	R$ 1200000000	127,800,000
Twenty Eight Debentures [Member]
IfrsStatementLineItems [Line Items]
Agreement clause in case of early maturity of debt		166,000,000
Twenty Nine Debentures [Member]
IfrsStatementLineItems [Line Items]
Agreement clause in case of early maturity of debt		R$ 175000000
U S D [Member]
IfrsStatementLineItems [Line Items]
Exchange rate | Number		5.5805					5.1967
Japan, Yen
IfrsStatementLineItems [Line Items]
Exchange rate | Number		0.04847					0.05043

Schedule of employees benefits

Schedule of employees benefits (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Salaries and payroll charges	R$ 58591	R$ 53107
Provision for vacation	226,127	207,906
Healthcare plan (i)	45,915	45,768
Provision for profit sharing (ii)	88,376	91,209
Consent Decree (TAC)	5,723	8,978
Knowledge Retention Program (PRC)	1,884	3,975
Total	R$ 426616	R$ 410943

Provisions (Details Narrative)

Provisions (Details Narrative) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	May 25, 2021
IfrsStatementLineItems [Line Items]
[custom:GuaranteeInsuranceForEscrowDepositRenewed-0]	R$ 555000		R$ 600000
Tax Claim [Member]
IfrsStatementLineItems [Line Items]
[custom:TaxDeficiencyNoticeRelatedToSewageServices]	857,688	R$ 731809
Other Concession Related Legal Proceedings [Member]
IfrsStatementLineItems [Line Items]
[custom:IndemnitiesReceivable-0]	R$ 27539	R$ 27539

Labor and social obligations (D

Labor and social obligations (Details Narrative) - Health Plan Medical Assistance [Member] - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Average gross payroll	8.50%	7.79%
Wages and salaries	R$ 232850	R$ 212681

Schedule of pension plan benefi

Schedule of pension plan benefits (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Present value of defined benefit obligations	R$ 4956089	R$ 5662521	R$ 6113349
Fair value of the plan's assets	2,634,427	2,793,927	2,752,417
Liability as per statement of financial position - pension obligations	(2,321,662)	(2,868,594)
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Present value of defined benefit obligations	(2,764,027)	(3,112,980)	(3,067,094)
Fair value of the plan's assets	2,634,427	2,793,927	2,752,417
Liability as per statement of financial position - pension obligations	(129,600)	(319,053)
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Present value of defined benefit obligations	(2,192,062)	(2,549,541)	(3,046,255)
Fair value of the plan's assets
Liability as per statement of financial position - pension obligations	R$ 2192062	R$ 2549541

Schedule of reconciliation of d

Schedule of reconciliation of defined benefit obligations (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Defined benefit obligation, beginning	R$ 5662521	R$ 6113349
Current service cost	(32,777)	(40,404)
Interest cost	(363,951)	(414,747)
Actuarial (gains)/losses recorded as other comprehensive income	745,160	585,968
Benefits paid	358,000	320,011
Defined benefit obligation, ending	(4,956,089)	(5,662,521)	R$ 6113349
Defined benefit obligation, ending	(4,956,089)	(5,662,521)	(6,113,349)
Fair value of the plan's assets, beginning	2,793,927	2,752,417
Expected return on the plan assets	184,687	187,317	192,965
Expected Company's contributions	35,368	36,010
Expected participants' contributions	30,551	36,608
Benefits paid	(172,614)	(138,366)
Actuarial gains/(losses) included in other comprehensive income (loss)	(237,492)	(80,059)	445,206
Fair value of the plan's assets, ending	2,634,427	2,793,927	2,752,417
(Deficit)/Surplus	(2,321,662)	(2,868,594)
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Defined benefit obligation, beginning	(3,112,980)	(3,067,094)
Current service cost	(32,777)	(40,404)
Interest cost	(205,707)	(208,485)
Actuarial (gains)/losses recorded as other comprehensive income	414,823	64,637
Benefits paid	172,614	138,366
Defined benefit obligation, ending	(2,764,027)	(3,112,980)	(3,067,094)
Defined benefit obligation, ending	(2,764,027)	(3,112,980)	(3,067,094)
Fair value of the plan's assets, beginning	2,793,927	2,752,417
Expected return on the plan assets	184,687	187,317	192,965
Expected Company's contributions	35,368	36,010
Expected participants' contributions	30,551	36,608
Benefits paid	(172,614)	(138,366)
Actuarial gains/(losses) included in other comprehensive income (loss)	(237,492)	(80,059)	445,206
Fair value of the plan's assets, ending	2,634,427	2,793,927	2,752,417
(Deficit)/Surplus	(129,600)	(319,053)
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Defined benefit obligation, beginning	(2,549,541)	(3,046,255)
Current service cost
Interest cost	(158,244)	(206,262)
Actuarial (gains)/losses recorded as other comprehensive income	330,337	521,331
Benefits paid	185,386	181,645
Defined benefit obligation, ending	(2,192,062)	(2,549,541)	(3,046,255)
Defined benefit obligation, ending	(2,192,062)	(2,549,541)	(3,046,255)
Fair value of the plan's assets, beginning
Expected return on the plan assets
Expected Company's contributions
Expected participants' contributions
Benefits paid
Actuarial gains/(losses) included in other comprehensive income (loss)
Fair value of the plan's assets, ending
(Deficit)/Surplus	R$ 2192062	R$ 2549541

Schedule of (gains)_losses, due

Schedule of (gains)/losses, due to changes in assumptions (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	R$ 745160	R$ 585968	R$ 790473
Actuarial gains/(losses) recorded as other comprehensive income	(237,492)	(80,059)	445,206
Total gains/(losses)	507,668	505,909	(345,267)
Deferred income tax and social contribution - G1 Plan	(60,292)	5,243	(17,792)
Valuation adjustments to equity	447,376	511,152	(363,059)
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	414,823	64,637	(392,876)
Actuarial gains/(losses) recorded as other comprehensive income	(237,492)	(80,059)	445,206
Total gains/(losses)	177,331	(15,422)	52,330
Deferred income tax and social contribution - G1 Plan	(60,292)	5,243	(17,792)
Valuation adjustments to equity	117,039	(10,179)	34,538
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	330,337	521,331	(397,597)
Actuarial gains/(losses) recorded as other comprehensive income
Total gains/(losses)	330,337	521,331	(397,597)
Deferred income tax and social contribution - G1 Plan
Valuation adjustments to equity	R$ 330337	R$ 521331	R$ 397597

Schedule of amounts recognized

Schedule of amounts recognized in income statement (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Cost of service, net	R$ 2227	R$ 4608	R$ 235976
Interest cost rates	363,951	414,747	224,429
Expected return on the plan's assets	(184,687)	(187,317)	(192,965)
Expected return on the plan's assets	184,687	187,317	192,965
Amount received from State of Sao Paulo (undisputed)	(91,657)	(95,452)	(97,300)
Total expenses	89,834	136,586	170,140
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Cost of service, net	2,227	4,608	8,609
Interest cost rates	205,707	208,485	224,429
Expected return on the plan's assets	(184,687)	(187,317)	(192,965)
Expected return on the plan's assets	184,687	187,317	192,965
Amount received from State of Sao Paulo (undisputed)
Total expenses	23,247	25,776	40,073
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Cost of service, net			227,367
Interest cost rates	158,244	206,262
Expected return on the plan's assets
Expected return on the plan's assets
Amount received from State of Sao Paulo (undisputed)	(91,657)	(95,452)	(97,300)
Total expenses	R$ 66587	R$ 110810	R$ 130067

Obligations_ maturity_ (Details

Obligations’ maturity: (Details) R$ in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Payment of benefits expected in 2021	R$ 198074
Payment of benefits expected in 2022	188,437
Payment of benefits expected in 2023	178,787
Payment of benefits expected in 2024	169,738
Payment of benefits expected in 2025 or after	2,028,991
Payment of benefits expected	R$ 2764027
Duration	11 years 7 months 17 days
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Payment of benefits expected in 2021	R$ 179875
Payment of benefits expected in 2022	173,944
Payment of benefits expected in 2023	167,140
Payment of benefits expected in 2024	159,604
Payment of benefits expected in 2025 or after	1,511,499
Payment of benefits expected	R$ 2192062
Duration	9 years 4 months 24 days

Actuarial assumptions_ (Details

Actuarial assumptions: (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Discount rate - actual rate (NTN-B)	5.53%	3.44%	3.37%
Inflation rate	3.00%	3.25%	3.50%
Nominal rate of salary growth	5.06%	5.32%	5.57%
Mortality table	AT-2000	AT-2000	AT-2000
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Discount rate - actual rate (NTN-B)	5.26%	3.07%	3.36%
Inflation rate	3.00%	3.25%	3.50%
Nominal rate of salary growth	5.06%	5.32%	5.57%
Mortality table	AT-2000	AT-2000	AT-2000

Sensitivity analysis of the def

Sensitivity analysis of the defined benefit pension plan as of December 31, 2021 regarding the changes in the main assumptions are: (Details)	12 Months Ended
	Dec. 31, 2021
G 1 Plan [Member] | Discount Rate [Member] | Increase Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Decrease of R$ 244,999
G 1 Plan [Member] | Discount Rate [Member] | Decrease Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Increase of R$ 289,735
G 1 Plan [Member] | Life Expectation [Member] | Increase Of One Year [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Increase of R$ 61,361
G 1 Plan [Member] | Life Expectation [Member] | Decrease Of One Year [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Decrease of R$ 56,181
G 1 Plan [Member] | Wage Increase Rate [Member] | Increase Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Increase of R$ 19,402
G 1 Plan [Member] | Wage Increase Rate [Member] | Decrease Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Decrease of R$ 16,464
G 0 Plan [Member] | Discount Rate [Member] | Increase Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Decrease of R$ 158,221
G 0 Plan [Member] | Discount Rate [Member] | Decrease Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Increase of R$ 180,948
G 0 Plan [Member] | Life Expectation [Member] | Increase Of One Year [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Increase of R$ 101,021
G 0 Plan [Member] | Life Expectation [Member] | Decrease Of One Year [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Decrease of R$ 90,081
G 0 Plan [Member] | Wage Increase Rate [Member] | Increase Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Increase of R$ 227,529
G 0 Plan [Member] | Wage Increase Rate [Member] | Decrease Of One Percent [Member]
IfrsStatementLineItems [Line Items]
Impact on present value of the defined benefit obligations	Decrease of R$ 202,363

Estimated expenses for the comi

Estimated expenses for the comig year (Details) - G 1 Plan [Member] R$ in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)
IfrsStatementLineItems [Line Items]
Cost of services, net	R$ 1020
Interest costs	231,745
Net profitability on financial assets	(221,079)
Expenditures to be recognized by the employer	R$ 11686

Schedule Of Plan_s Assets (Deta

Schedule Of Plan’s Assets (Details) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan Obligations
Total fixed income	R$ 1613153	R$ 1811164
Percentage of total fixed income	61.20%	64.80%
Total equities	R$ 261665	R$ 311958
Percentage of total equities	9.90%	11.20%
Total structured investments	R$ 599970	R$ 575943
Percentage of total structured investments	22.80%	20.60%
Other	R$ 159639	R$ 94862
Percentage of other	6.10%	3.40%
Fair value of the plan's assets	R$ 2634427	R$ 2793927	R$ 2752417
Percentage of fair value of the plan's assets	100.00%

Estimated expenses for 2022 (De

Estimated expenses for 2022 (Details) - G 0 Plan [Member] R$ in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)
IfrsStatementLineItems [Line Items]
Interest cost rates	R$ 176953
Expense to be recognized	R$ 176953

Reconciliation of expenses with

Reconciliation of expenses with pension obligations (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Subtotal	R$ 112400	R$ 158344	R$ 192601
Expenses capitalized in assets	(4,118)	(4,904)	(6,022)
Other	5,527	5,841	8,040
Pension plan obligations (Note 29)	113,809	159,281	194,619
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Subtotal	23,247	25,776	40,073
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Subtotal	66,587	110,810	130,067
Sabesprev Mais Plan [Member]
IfrsStatementLineItems [Line Items]
Subtotal	22,406	21,700	22,461
V I V E S T Plan [Member]
IfrsStatementLineItems [Line Items]
Subtotal	R$ 160	R$ 58

Pension plan obligations (Detai

Pension plan obligations (Details Narrative) R$ in Thousands	12 Months Ended
	Dec. 31, 2021BRL (R$)Number	Dec. 31, 2020BRL (R$)Number
Sabesprev Mais One [Member]
IfrsStatementLineItems [Line Items]
[custom:ActiveParticipantsOfPlan]	9,463	9,587
V I V E S T [Member]
IfrsStatementLineItems [Line Items]
[custom:NumberOfParticipantsOfRetirementBenefitPlanNotReceivingBenefits] | Number	46	24
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Description of defined benefit plan	0.99% of the portion of the salary of participation up to 20 salaries; and
[custom:DescriptionOfDefinedBenefitPlan1]	8.39% of the surplus, if any, of the portion of the salary of participation over 20 salaries.
Number of participants of retirement benefit plan receiving benefits | Number	2,930	3,512
[custom:NumberOfParticipantsOfRetirementBenefitPlanNotReceivingBenefits] | Number	8,109	7,580
Decrease (increase) in net defined benefit liability (asset) resulting from resulting from contributions to plan by employer	R$ 35368	R$ 36009
[custom:ContributionParticipants]	30,551	36,608
[custom:ActuarialDeficit]	28,829	26,326
[custom:ActuarialDeficitParticipants]	R$ 23609	R$ 26895
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
[custom:ActiveParticipantsOfPlan]	8	10
[custom:BeneficiariesRetireesAndSurvivors]	1,794	1,862

Services payable (Details Narra

Services payable (Details Narrative) - BRL (R$) R$ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Services payable	R$ 469027	R$ 453750

Share capital (Details)

Share capital (Details) - shares		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Number of shares		683,509,869	683,509,869	683,509,869
Percentage of shares		100.00%	100.00%
State Department Of Finance [Member]
IfrsStatementLineItems [Line Items]
Number of shares		343,506,664,000	343,507,729,000
Percentage of shares		50.30%	50.26%
Other Shareholders In Brazil [Member]
IfrsStatementLineItems [Line Items]
Number of shares	[1]	234,965,971,000	254,868,646,000
Percentage of shares	[1]	34.40%	37.29%
Other Shareholders Abroads [Member]
IfrsStatementLineItems [Line Items]
Number of shares	[2],[3]	105,037,234,000	85,133,494,000
Percentage of shares	[2],[3]	15.30%	12.45%
[1]	As of December 31, 2021, the common shares traded in Brazil were held by 40,428 shareholders. It includes six shares held by Companhia Paulista de Parcerias (CPP), which is controlled by the São Paulo State Government.
[2]	Each ADR corresponds to 1 share.
[3]	Shares traded as American Depositary Receipts (ADR) on the New York Stock Exchange, through The Bank New York Mellon, the depositary bank for the Company's ADRs.

Distribution of earnings (Detai

Distribution of earnings (Details) - BRL (R$) R$ / shares in Units, R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Profit for the year	R$ 2305869	R$ 973318	R$ 3367517
(-) Legal reserve - 5%	115,293	48,666	168,376	R$ 168376
Distribution of earnings	2,190,576	924,652	3,199,141
Minimum mandatory dividend - 25%	R$ 547645	R$ 231163	R$ 799785
Dividend per share and per ADS	R$ 0.80122	R$ 0.33820	R$ 1.17012

Allocation of the profit for th

Allocation of the profit for the year (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Profit for the year	R$ 2305869	R$ 973318	R$ 3367517
Legal reserve	115,293	48,666	168,376	R$ 168376
Minimum mandatory dividends	547,645	231,163	799,785
Additional proposed dividends	96,700	40,806	141,203
Investment reserve recorded	R$ 1546231	R$ 652863	R$ 2258153

Other comprehensive loss (Detai

Other comprehensive loss (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Other comprehensive loss, ending	R$ 46374	R$ 401002
Actuarial gains (losses)	447,376	511,152	R$ 363059
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Other comprehensive loss, ending	212,114	95,075
Actuarial gains (losses)	117,039
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Other comprehensive loss, ending	(165,740)	R$ 496077
Actuarial gains (losses)	R$ 330337

Schedule of earnings per share,

Schedule of earnings per share, basic and diluted (Details) R$ in Thousands	12 Months Ended
	Dec. 31, 2021$ / shares	Dec. 31, 2021BRL (R$)shares	Dec. 31, 2020$ / shares	Dec. 31, 2020BRL (R$)shares	Dec. 31, 2019$ / shares	Dec. 31, 2019BRL (R$)shares
Earnings attributable to Company’s owners | R$		R$ 2305869		R$ 973318		R$ 3367517
Weighted average number of common shares issued | shares		683,509,869		683,509,869		683,509,869
Basic and diluted earnings per share (reais per share) | $ / shares	$ 3.37		$ 1.42		$ 4.93

Equity (Details Narrative)

Equity (Details Narrative) - BRL (R$) R$ / shares in Units, R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Paid-in capital value	R$ 15000
Paid-in capital shares		683,509,869
Dividends paid, classified as operating activities	547,645	R$ 40806
[custom:SurplusMinimumMandatory]		26,376
[custom:DividendsPaidClassifiedAsOperatingActivities1]		231,163
[custom:AdditionalProposedDividends]	96,700	40,806	R$ 141203
[custom:TotalingProposedDividends]	R$ 644345	R$ 271969
Dividends paid, ordinary shares per share	R$ 0.9427	R$ 0.3979
[custom:DividendsWithholdingIncomeTaxRecognizedInCurrentLiabilities-0]	R$ 41069	R$ 14430
[custom:DividendsWitheldIncomeTax-0]	41,069	14,430
[custom:DeclaredDividendPayables-0]	548,006	231,611
[custom:DeclaredDividendPayables1-0]	547,645	231,163
[custom:DividendsWitheldIncomeTax1-0]	R$ 361	448
[custom:DescriptionOfLegalReserve]	Earnings reserve - legal reserve: created by allocating 5% of the net income for the year up to the limit of 20% of the share capital. The Company may not create the legal reserve in the year in which the balance of this reserve, plus the amount of the capital reserves, exceeds 30% of the share capital. The purpose of the legal reserve is to ensure the integrity of the share capital. It can only be used to offset losses or increase capital, but not to pay dividends
[custom:InvestmentReserve]	R$ 8297489	R$ 6751258
Retained earnings	R$ 1546231

Schedule of operating segment i

Schedule of operating segment information (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Gross operating revenue	R$ 20680945		R$ 18874396		R$ 19080598
Gross sales deductions	(1,189,884)		(1,076,855)		(1,096,944)
Net operating revenue	19,491,061		17,797,541		17,983,654
Costs, selling and administrative expenses	(15,393,720)		(13,426,960)		(12,256,984)
Income from operations before other operating expenses, net and equity accounting	4,097,341		4,370,581		5,726,670
Other operating income/(expenses), net	(21,841)		107,656		(18,748)
Equity accounting	22,079		14,136		3,701
Financial result, net	(927,423)		(3,166,371)		(1,033,681)
Income from operations before taxes	3,170,156		1,326,002		4,677,942
Depreciation and amortization	(2,253,322)		(2,037,112)		(1,780,094)
Sanitations [Member]
IfrsStatementLineItems [Line Items]
Gross operating revenue	16,304,206	[1]	15,157,780	[2]	16,134,032	[3]
Gross sales deductions	(1,189,884)	[1]	(1,076,855)	[2]	(1,096,944)	[3]
Net operating revenue	15,114,322	[1]	14,080,925	[2]	15,037,088	[3]
Costs, selling and administrative expenses	(11,115,383)	[1]	(9,796,821)	[2]	(9,375,590)	[3]
Income from operations before other operating expenses, net and equity accounting	3,998,939	[1]	4,284,104	[2]	5,661,498	[3]
Depreciation and amortization	(2,253,322)	[1]	(2,037,112)	[2]	(1,780,094)	[3]
Reconciliations [Member]
IfrsStatementLineItems [Line Items]
Gross operating revenue	4,376,739	[4]	3,716,616	[5]	2,946,566	[6]
Gross sales deductions		[4]		[5]		[6]
Net operating revenue	4,376,739	[4]	3,716,616	[5]	2,946,566	[6]
Costs, selling and administrative expenses	(4,278,337)	[4]	(3,630,139)	[5]	(2,881,394)	[6]
Income from operations before other operating expenses, net and equity accounting	R$ 98402	[4]	R$ 86477	[5]	R$ 65172	[6]
[1]	See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information;
[2]	See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information;
[3]	See note 33 for further information about non-cash items, other than depreciation and amortization that impact segment results, and for additionals to long-lived asset information;
[4]	Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (b).
[5]	Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (e).
[6]	Construction revenue and related costs not reported to the CODM. Revenue from construction is recognized in accordance with IFRIC 12 (Concession Agreements) and IFRS 15 (Revenue from Contracts with Customers), as all performance obligations are satisfied over time. See Note 14 (b).

As of December 31, 2021, the Co

As of December 31, 2021, the Company’s insurance was as follows: (Details) R$ in Thousands	Dec. 31, 2021BRL (R$)
IfrsStatementLineItems [Line Items]
Coverage	R$ 5349105
Specified Risk [Member]
IfrsStatementLineItems [Line Items]
Coverage	2,185,827
Engineering Risk [Member]
IfrsStatementLineItems [Line Items]
Coverage	2,254,238
Guarantee Insurance Escrow Deposit [Member]
IfrsStatementLineItems [Line Items]
Coverage	600,000
Civil Liability Directors And Officers [Member]
IfrsStatementLineItems [Line Items]
Coverage	100,000
Civil Liability Work [Member]
IfrsStatementLineItems [Line Items]
Coverage	172,140
Civil Liabilitys Operations [Member]
IfrsStatementLineItems [Line Items]
Coverage	10,000
Other Insurance Coverages [Member]
IfrsStatementLineItems [Line Items]
Coverage	R$ 26900

Revenue from sanitation service

Revenue from sanitation services: (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Net operating revenue	R$ 19491061	R$ 17797541	R$ 17983654
Sanitation Sao Paolo [Member]
IfrsStatementLineItems [Line Items]
Net operating revenue	11,529,229	10,722,384	11,849,776
Regional System [Member]
IfrsStatementLineItems [Line Items]
Net operating revenue	4,774,977	4,435,396	4,284,256
Sanitation Services [Member]
IfrsStatementLineItems [Line Items]
Net operating revenue	R$ 16304206	R$ 15157780	R$ 16134032

Reconciliation from gross opera

Reconciliation from gross operating income to net operating income: (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue from sanitation services (i)	R$ 16304206	R$ 15157780	R$ 16134032
Construction revenue	4,376,739	3,716,616	2,946,566
Sales tax	(1,121,905)	(1,009,358)	(1,035,051)
Regulatory, Control and Oversight Fee (TRCF)	(67,979)	(67,497)	(61,893)
Net revenue	19,491,061	17,797,541	R$ 17983654
[custom:AmountCorrespondingToTrcfChargedFromCustomers]	R$ 80329	R$ 72962

Schedule of operating costs and

Schedule of operating costs and expenses (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Operating costs	R$ 12800042	R$ 11179667	R$ 10137637
Selling expenses	825,879	751,286	803,404
Allowance for doubtful accounts	643,730	444,826	128,099
Administrative expenses	1,124,069	1,051,181	1,187,844
Administrative expenses	(1,124,069)	(1,051,181)	(1,187,844)
Total	(15,393,720)	(13,426,960)	(12,256,984)
Salaries Payroll Charges And Benefits [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(2,026,202)	(1,958,395)	(1,938,265)
Selling expenses	(265,435)	(271,565)	(270,549)
Administrative expenses	(250,557)	(257,829)	(278,507)
Administrative expenses	250,557	257,829	278,507
Total	(2,542,194)	(2,487,789)	(2,487,321)
Pension Obligations [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(36,771)	(37,281)	(49,564)
Selling expenses	(4,868)	(5,059)	(6,848)
Administrative expenses	(72,170)	(116,941)	(138,207)
Administrative expenses	72,170	116,941	138,207
Total	(113,809)	(159,281)	(194,619)
Construction Costs [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(4,278,337)	(3,630,139)	(2,881,394)
Total	(4,278,337)	(3,630,139)	(2,881,394)
General Supplies [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(314,111)	(244,054)	(259,401)
Selling expenses	(7,976)	(5,471)	(10,332)
Administrative expenses	(11,209)	(14,237)	(3,216)
Administrative expenses	11,209	14,237	3,216
Total	(333,296)	(263,762)	(272,949)
Treatment Supplies [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(364,542)	(338,756)	(310,380)
Total	(364,542)	(338,756)	(310,380)
Outside Services [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(1,517,196)	(1,251,839)	(1,250,890)
Selling expenses	(343,763)	(290,512)	(360,190)
Administrative expenses	(250,801)	(230,054)	(197,357)
Administrative expenses	250,801	230,054	197,357
Total	(2,111,760)	(1,772,405)	(1,808,437)
Electricity One [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(1,462,776)	(1,214,831)	(1,140,160)
Selling expenses	(1,340)	(1,200)	(1,333)
Administrative expenses	(1,715)	(1,359)	(1,436)
Administrative expenses	1,715	1,359	1,436
Total	(1,465,831)	(1,217,390)	(1,142,929)
General Expenses [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(717,352)	(622,113)	(647,804)
Selling expenses	(136,107)	(118,278)	(122,503)
Administrative expenses	(357,564)	(257,693)	(407,250)
Administrative expenses	357,564	257,693	407,250
Total	(1,211,023)	(998,084)	(1,177,557)
Depreciation And Amortization [Member]
IfrsStatementLineItems [Line Items]
Operating costs	(2,082,755)	(1,882,259)	(1,659,779)
Selling expenses	(66,390)	(59,201)	(31,649)
Administrative expenses	(104,177)	(95,652)	(88,666)
Administrative expenses	104,177	95,652	88,666
Total	(2,253,322)	(2,037,112)	(1,780,094)
Bad Debt Expense Net [Member]
IfrsStatementLineItems [Line Items]
Allowance for doubtful accounts	(643,730)	(444,826)	(128,099)
Total	(643,730)	(444,826)	(128,099)
Tax Expense [Member]
IfrsStatementLineItems [Line Items]
Administrative expenses	(75,876)	(77,416)	(73,205)
Administrative expenses	75,876	77,416	73,205
Total	R$ 75876	R$ 77416	R$ 73205

Schedule of financial income (e

Schedule of financial income (expenses) (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
IfrsStatementLineItems [Line Items]
Financial expenses	R$ 1448295	R$ 1324759	R$ 1173425
Financial expenses	(1,448,295)	(1,324,759)	(1,173,425)
Financial income	472,408	336,731	372,842
Financial income (expenses), net before exchange rate changes	(975,887)	(988,028)	(800,583)
Exchange rate changes, net	48,464	(2,178,343)	(233,098)
Financial income (expenses), net	(927,423)	(3,166,371)	(1,033,681)
Interet And Charges Local Currency [Member]
IfrsStatementLineItems [Line Items]
Financial expenses	(517,235)	(348,050)	(331,367)
Financial expenses	517,235	348,050	331,367
Interet And Charges Foreign Currency [Member]
IfrsStatementLineItems [Line Items]
Financial expenses	(46,793)	(136,257)	(165,421)
Financial expenses	46,793	136,257	165,421
Other Financial Expenses [Member]
IfrsStatementLineItems [Line Items]
Financial expenses	(315,013)	(328,413)	(344,508)
Financial expenses	315,013	328,413	344,508
Income Tax Over International Remittance [Member]
IfrsStatementLineItems [Line Items]
Financial expenses		(15,134)	(17,650)
Financial expenses		15,134	17,650
Inflation Adjustment Loans And Financing [Member]
IfrsStatementLineItems [Line Items]
Financial expenses	(225,791)	(86,938)	(44,802)
Financial expenses	225,791	86,938	44,802
Other Inflation Adjustments [Member]
IfrsStatementLineItems [Line Items]
Financial expenses	(172,632)	(142,313)	(107,584)
Financial expenses	172,632	142,313	107,584
Interest Inflation Adjustments On Provisions [Member]
IfrsStatementLineItems [Line Items]
Financial expenses	(170,831)	(267,654)	(162,093)
Financial expenses	170,831	267,654	162,093
Inflation Adjustment Gains [Member]
IfrsStatementLineItems [Line Items]
Financial income	198,907	120,957	91,180
Income On Financial Investments [Member]
IfrsStatementLineItems [Line Items]
Financial income	150,632	75,522	151,622
Financial Interest Income [Member]
IfrsStatementLineItems [Line Items]
Financial income	145,866	162,576	150,054
C O F I N S And Pasep [Member]
IfrsStatementLineItems [Line Items]
Financial income	(23,038)	(22,328)	(20,028)
Other Financial Income [Member]
IfrsStatementLineItems [Line Items]
Financial income	41	4	14
Exchange Rate Changes Borrowing Financing [Member]
IfrsStatementLineItems [Line Items]
Exchange rate changes, net	48,522	(2,180,241)	(233,960)
Exchange Gains [Member]
IfrsStatementLineItems [Line Items]
Exchange rate changes, net	(36)	1,894	863
Other Exchange Rate Changes [Member]
IfrsStatementLineItems [Line Items]
Exchange rate changes, net	R$ 22	R$ 4	R$ 1

Schedule of other operating inc

Schedule of other operating income (expenses), net (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Other operating income, net	R$ 71877	R$ 70288	R$ 75667
Other operating expenses	93,718	(37,368)	94,415
Other operating income (expenses), net	R$ 21841	R$ 107656	R$ 18748

Below, the main unrecorded comm

Below, the main unrecorded committed amounts as of December 31, 2020: (Details) R$ in Thousands	Dec. 31, 2021BRL (R$)
IfrsStatementLineItems [Line Items]
Contractual obligations - expenses	R$ 2870300
Contractual obligations - investments	5,757,045
Total	8,627,345
Not later than one year [member]
IfrsStatementLineItems [Line Items]
Contractual obligations - expenses	1,147,112
Contractual obligations - investments	2,258,647
Total	3,405,759
Later than one year and not later than three years [member]
IfrsStatementLineItems [Line Items]
Contractual obligations - expenses	745,388
Contractual obligations - investments	1,741,424
Total	2,486,812
Later Than Three Year And Not Later Than Five Years [Member]
IfrsStatementLineItems [Line Items]
Contractual obligations - expenses	187,150
Contractual obligations - investments	1,425,790
Total	1,612,940
Later than five years [member]
IfrsStatementLineItems [Line Items]
Contractual obligations - expenses	790,650
Contractual obligations - investments	331,184
Total	R$ 1121834

Schedule of supplemental cash f

Schedule of supplemental cash flow information (Details) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2021		Dec. 31, 2020	Dec. 31, 2019
Supplemental Cash Flow Information
Total additions to contract assets (Note 14)	R$ 4759789	[1]	R$ 3948158	R$ 3532283
Total additions to intangible assets (Note 15 (b))	172,961		411,285	1,788,907
Items not affecting cash (see breakdown below)	(1,236,081)		(1,095,786)	(2,125,943)
Total additions to intangible assets as per statement of cash flows	3,696,669		3,299,657	3,195,247
Interest capitalized in the year (Note 14 (a))	300,792		238,330	233,251
Contractors payable	218,523		142,514	252,675
Program contract commitments			4,422	35,817
Public Private Partnership - São Lourenço PPP (Note 15 (g))				10,591
Performance agreements	478,177		314,720	78,296
Right of use	140,187		28,549	113,233
Construction margin (Note 26)	98,402		85,976	65,172
Agreement with the Municipality of Mauá			280,774
Agreement with the municipality of Santo André				1,336,908
Total	R$ 1236081		R$ 1095786	R$ 2125943
[1]	The largest additions of the period are located in the municipalities of São Paulo, Guarulhos and Praia Grande, in the amounts of R$ 2,419 million, R$ 180 million and R$ 158 million, respectively.

Events after the reporting pe_2

Events after the reporting period (Details Narrative)	Mar. 18, 2022	Mar. 17, 2022
Description of issue debentures	As of March 18, 2022, the Company raised R$ 1.0 billion from the 30th issue of simple, unsecured debentures, not convertible into shares, in two series, under CVM Instruction 476. The first and second series will mature in March 2027 and March 2029, respectively. The first series, totaling R$ 500.0 million, yields CDI + 1.30% p.a., with semi-annual interest payments. The second series, totaling R$ 500.0 million, yields CDI + 1.58% p.a., also with semi-annual interest payments. The proceeds from the Issue will be used to refinance financial commitments maturing in 2022 and to recompose and reinforce the Company’s cash position.
Description of tariff adjustment		As of March 17, 2022, ARSESP published Resolution 1,278, which addresses the 2022 tariff adjustment, in which the Company highlights the following points:
Description of artical		Article 1. Approve the total adjustment of twelve point eight zero one nine percent (12.8019%) on the tariffs charged by Sabesp, according to the exhibits to this resolution, which consists of:
Description of artical approve		I - Inflation from February 2021 to February 2022, measured by the IPCA, of 10.5437%.
Description of artical approve efficiency factor		II - Efficiency factor (X Factor) to be discounted, of 0.2142%.
Description of compensatory adjustment		III - Compensatory adjustment of 2.3932%, according to the calculation provided in NT.F.0010-2022.
Description of artical discounted		IV – GQI 2020 to be discounted, of 0.1490%, according to the calculation provided in NT.F.0010-2022.