UDR (UDR) 10-Q 27 Apr 22 2022 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2022	Apr. 25, 2022
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2022
Entity File Number	1-10524
Entity Registrant Name	UDR, Inc.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	54-0857512
Entity Address, Address Line One	1745 Shea Center Drive, Suite 200
Entity Address, City or Town	Highlands Ranch
Entity Address, State or Province	CO
Entity Address, Postal Zip Code	80129
City Area Code	720
Local Phone Number	283-6120
Title of 12(b) Security	Common Stock, par value $0.01
Trading Symbol	UDR
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		318,401,109
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000074208
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Real estate owned:
Real estate held for investment	$ 14,374,944	$ 14,352,234
Less: accumulated depreciation	(5,288,902)	(5,136,589)
Real estate held for investment, net	9,086,042	9,215,645
Real estate under development (net of accumulated depreciation of $951 and $507, respectively)	457,160	388,062
Total real estate owned, net of accumulated depreciation	9,543,202	9,603,707
Cash and cash equivalents	895	967
Restricted cash	26,032	27,451
Notes receivable, net	26,577	26,860
Investment in and advances to unconsolidated joint ventures, net	669,343	702,461
Operating lease right-of-use assets	196,578	197,463
Other assets	222,337	216,311
Total assets	10,684,964	10,775,220
Liabilities:
Secured debt, net	1,056,110	1,057,380
Unsecured debt, net	4,422,900	4,355,407
Operating lease liabilities	191,689	192,488
Real estate taxes payable	32,908	33,095
Accrued interest payable	25,700	45,980
Security deposits and prepaid rent	53,021	55,441
Distributions payable	130,369	124,729
Accounts payable, accrued expenses, and other liabilities	117,240	136,954
Total liabilities	6,029,937	6,001,474
Commitments and contingencies (Note 13)
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	1,262,144	1,299,442
Equity:
Common stock, $0.01 par value; 450,000,000 shares authorized at March 31, 2022 and December 31, 2021: 318,401,530 and 318,149,635 shares issued and outstanding at March 31, 2022 and December 31, 2021, respectively	3,184	3,181
Additional paid-in capital	6,891,707	6,884,269
Distributions in excess of net income	(3,549,788)	(3,485,080)
Accumulated other comprehensive income/(loss), net	2,805	(4,261)
Total stockholders' equity	3,392,673	3,442,874
Noncontrolling interests	210	31,430
Total equity	3,392,883	3,474,304
Total liabilities and equity	10,684,964	10,775,220
8.00% Series E Cumulative Convertible Preferred Stock
Equity:
Preferred stock, no par value; 50,000,000 shares authorized at March 31, 2022 and December 31, 2021:	44,764	44,764
Series F
Equity:
Preferred stock, no par value; 50,000,000 shares authorized at March 31, 2022 and December 31, 2021:	$ 1	$ 1

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Real estate owned:
Real estate under development accumulated depreciation	$ 951	$ 507
Equity:
Preferred stock, no par value	$ 0	$ 0
Preferred stock, shares authorized	50,000,000	50,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	450,000,000	450,000,000
Common stock, shares issued	318,401,530	318,149,635
Common stock, shares outstanding	318,401,530	318,149,635
8.00% Series E Cumulative Convertible Preferred Stock
Equity:
Preferred stock, dividend rate percentage	8.00%	8.00%
Preferred stock, shares issued	2,695,363	2,695,363
Preferred stock, shares outstanding	2,695,363	2,695,363
Series F
Equity:
Preferred stock, shares issued	12,455,650	12,582,575
Preferred stock, shares outstanding	12,455,650	12,582,575

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
REVENUES:
Rental income	$ 356,181	$ 299,826
Joint venture management and other fees	$ 1,085	$ 1,615
Type of revenue	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
Total revenues	$ 357,266	$ 301,441
OPERATING EXPENSES:
Property operating and maintenance	58,484	51,381
Real estate taxes and insurance	53,764	47,387
Property management	11,576	8,995
Other operating expenses	4,712	4,435
Real estate depreciation and amortization	163,622	144,088
General and administrative	14,908	12,736
Casualty-related charges/(recoveries), net	(765)	5,577
Other depreciation and amortization	3,075	2,601
Total operating expenses	309,376	277,200
Gain/(loss) on sale of real estate owned		50,829
Operating income	47,890	75,070
Income/(loss) from unconsolidated entities	5,412	4,922
Interest expense	(35,916)	(78,156)
Interest income and other income/(expense), net	(2,440)	2,057
Income/(loss) before income taxes	14,946	3,893
Tax (provision)/benefit, net	(343)	(619)
Net income/(loss)	14,603	3,274
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(879)	(154)
Net (income)/loss attributable to noncontrolling interests	(19)	(16)
Net income/(loss) attributable to UDR, Inc.	13,705	3,104
Distributions to preferred stockholders - Series E (Convertible)	(1,092)	(1,056)
Net income/(loss) attributable to common stockholders	$ 12,613	$ 2,048
Income/(loss) per weighted average common share - basic	$ 0.04	$ 0.01
Income/(loss) per weighted average common share - diluted	$ 0.04	$ 0.01
Weighted average number of common shares outstanding - basic	318,009	296,537
Weighted average number of common shares outstanding - diluted	319,680	297,026

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS)
Net income/(loss)	$ 14,603	$ 3,274
Other comprehensive income/(loss), including portion attributable to noncontrolling interests:
Unrealized holding gain/(loss)	7,193	127
(Gain)/loss reclassified into earnings from other comprehensive income/(loss)	387	446
Other comprehensive income/(loss), including portion attributable to noncontrolling interests	7,580	573
Comprehensive income/(loss)	22,183	3,847
Comprehensive (income)/loss attributable to noncontrolling interests	(1,412)	(213)
Comprehensive income/(loss) attributable to UDR, Inc.	$ 20,771	$ 3,634

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Preferred Stock	Common Stock	Paid-in Capital	Distributions in Excess of Net Income [Member]	Accumulated Other Comprehensive Income/(Loss) [Member]	Noncontrolling Interest	Total
Beginning Balance at Dec. 31, 2020	$ 44,765	$ 2,966	$ 5,881,383	$ (2,685,770)	$ (9,144)	$ 24,391	$ 3,258,591
Consolidated Statements of Changes in Equity
Net income/(loss) attributable to UDR, Inc.				3,104			3,104
Net income/(loss) attributable to noncontrolling interests						8	8
Redemption of noncontrolling interests in consolidated real estate						(125)	(125)
Long Term Incentive Plan Unit grants/(vestings), net						(9,601)	(9,601)
Other comprehensive income/(loss)					530		530
Issuance/(forfeiture) of common and restricted shares, net		1	(197)				(196)
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership		1	4,496				4,497
Common stock distributions declared				(107,651)			(107,651)
Preferred stock distributions declared-Series E				(1,056)			(1,056)
Adjustment to reflect redemption value of redeemable noncontrolling interests				(131,700)			(131,700)
Ending Balance at Mar. 31, 2021	44,765	2,968	5,885,682	(2,923,073)	(8,614)	14,673	3,016,401
Beginning Balance at Dec. 31, 2021	44,765	3,181	6,884,269	(3,485,080)	(4,261)	31,430	3,474,304
Consolidated Statements of Changes in Equity
Net income/(loss) attributable to UDR, Inc.				13,705			13,705
Long Term Incentive Plan Unit grants/(vestings), net						(31,220)	(31,220)
Other comprehensive income/(loss)					7,066		7,066
Issuance/(forfeiture) of common and restricted shares, net		1	(1,041)				(1,040)
Issuance of common shares through public offering, net			(99)				(99)
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership		2	8,578				8,580
Common stock distributions declared				(121,068)			(121,068)
Preferred stock distributions declared-Series E				(1,092)			(1,092)
Adjustment to reflect redemption value of redeemable noncontrolling interests				43,747			43,747
Ending Balance at Mar. 31, 2022	$ 44,765	$ 3,184	$ 6,891,707	$ (3,549,788)	$ 2,805	$ 210	$ 3,392,883

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Common stock distributions declared per share	$ 0.38	$ 0.3625
8.00% Series E Cumulative Convertible Preferred Stock
Preferred stock distributions declared	$ 0.4114	$ 0.3925

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating Activities
Net income/(loss)	$ 14,603	$ 3,274
Adjustments to reconcile net income/(loss) to net cash provided by/(used in) operating activities:
Depreciation and amortization	166,697	146,689
(Gain)/loss on sale of real estate owned		(50,829)
(Income)/loss from unconsolidated entities	(5,412)	(4,922)
Return on investment in unconsolidated joint ventures	12,352	1,094
Amortization of share-based compensation	6,371	4,912
Loss on extinguishment of debt, net		41,950
Other	6,422	2,766
Changes in operating assets and liabilities:
(Increase)/decrease in operating assets	4,979	18
Increase/(decrease) in operating liabilities	(44,992)	(21,347)
Net cash provided by/(used in) operating activities	161,020	123,605
Investing Activities
Acquisition of real estate assets		(23,693)
Proceeds from sales of real estate investments, net		154,857
Development of real estate assets	(56,755)	(32,683)
Capital expenditures and other major improvements - real estate assets	(34,615)	(28,424)
Capital expenditures - non-real estate assets	(9,677)	(3,041)
Investment in unconsolidated joint ventures and partnerships	(48,233)	(48,604)
Distributions received from unconsolidated joint ventures and partnerships	68,185	32,648
Purchase deposits on pending acquisitions	(6,000)	(12,821)
Repayment/(issuance) of notes receivable, net	284	2,800
Net cash provided by/(used in) investing activities	(86,811)	41,039
Financing Activities
Payments on secured debt	(280)	(270)
Payments on unsecured debt		(300,000)
Net proceeds from the issuance of unsecured debt		298,776
Net proceeds/(repayment) of commercial paper	60,000	20,000
Net proceeds/(repayment) of revolving bank debt	7,648	(10,210)
Proceeds from the issuance of common shares through public offering, net	(99)
Distributions paid to redeemable noncontrolling interests	(7,862)	(8,517)
Distributions paid to preferred stockholders	(1,050)	(1,045)
Distributions paid to common stockholders	(115,405)	(106,833)
Payment of prepayment and extinguishment costs		(40,769)
Other	(18,652)	(5,347)
Net cash provided by/(used in) financing activities	(75,700)	(154,215)
Net increase/(decrease) in cash, cash equivalents, and restricted cash	(1,491)	10,429
Cash, cash equivalents, and restricted cash, beginning of year	28,418	24,171
Cash, cash equivalents, and restricted cash, end of period	26,927	34,600
Supplemental Information:
Interest paid during the period, net of amounts capitalized	55,126	56,281
Operating cash flows from operating leases	3,126	3,126
Cash paid/(refunds received) for income taxes	222	(36)
Non-cash transactions:
Secured debt assumed upon acquisition of real estate assets		58,464
Redeemable long-term incentive plan units	37,383	14,578
Development costs and capital expenditures incurred, but not yet paid	43,571	31,628
Conversion of Operating Partnership and DownREIT Partnership noncontrolling interests to common stock (142,984 shares in 2022 and 116,997 shares in 2021)	8,580	4,497
Distribution of equity securities from unconsolidated real estate technology investments	6,508
Dividends declared, but not yet paid	$ 130,369	$ 116,693

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS - SUPPLEMENTAL - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
The following reconciles cash, cash equivalents, and restricted cash to amounts as shown above:
Cash and cash equivalents	$ 895	$ 967	$ 1,172	$ 1,409
Restricted cash	26,032	27,451	33,428	22,762
Total cash, cash equivalents, and restricted cash as shown above	$ 26,927	$ 28,418	$ 34,600	$ 24,171

CONSOLIDATED STATEMENTS OF CA_3

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Non-cash transactions:
Conversion of OP Units into common shares	142,984	116,997

BASIS OF PRESENTATION

BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2022
BASIS OF PRESENTATION
BASIS OF PRESENTATION	1. BASIS OF PRESENTATION Organization and Formation UDR, Inc. (“UDR,” the “Company,” “we,” or “our”) is a self-administered real estate investment trust, or REIT, that owns, operates, acquires, renovates, develops, redevelops, and manages apartment communities in targeted markets located in the United States. At March 31, 2022, our consolidated apartment portfolio consisted of 160 communities with a total of 53,503 apartment homes located in 21 markets. In addition, the Company has an ownership interest in 6,489 completed or to-be-completed apartment homes through unconsolidated joint ventures or partnerships, including 3,652 apartment homes owned by entities in which we hold preferred equity investments. Basis of Presentation The accompanying consolidated financial statements of UDR include its wholly-owned and/or controlled subsidiaries (see Note 4, Variable Interest Entities The accompanying consolidated financial statements include the accounts of UDR and its subsidiaries, including United Dominion Realty, L.P. (the “Operating Partnership” or the “OP”) and UDR Lighthouse DownREIT L.P. (the “DownREIT Partnership”). As of March 31, 2022, there were 186.2 million units in the Operating Partnership (“OP Units”) outstanding, of which 176.3 million OP Units (including 0.1 million of general partnership units), or 94.7%, were owned by UDR and 9.9 million OP Units, or 5.3%, were owned by outside limited partners. As of March 31, 2022, there were 32.4 million units in the DownREIT Partnership (“DownREIT Units”) outstanding, of which 20.8 million, or 64.2%, were owned by UDR and its subsidiaries and 11.6 million, or 35.8%, were owned by outside limited partners. The consolidated financial statements of UDR include the noncontrolling interests of the unitholders in the Operating Partnership and DownREIT Partnership. The accompanying interim unaudited consolidated financial statements have been prepared according to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and note disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States have been condensed or omitted according to such rules and regulations, although management believes that the disclosures are adequate to make the information presented not misleading. In the opinion of management, all adjustments and eliminations necessary for the fair presentation of our financial position as of March 31, 2022, and results of operations for the three months ended March 31, 2022 and 2021, have been included. Such adjustments are normal and recurring in nature. The interim results presented are not necessarily indicative of results that can be expected for a full year. The accompanying interim unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes for the year ended December 31, 2021 appearing in UDR’s Annual Report on Form 10-K, filed with the SEC on February 15, 2022. The accompanying interim unaudited consolidated financial statements are presented in accordance with U.S. generally accepted accounting principles (“GAAP”). GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the interim unaudited consolidated financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates. All significant intercompany accounts and transactions have been eliminated in consolidation. The Company evaluated subsequent events through the date its financial statements were issued. No significant recognized or non-recognized subsequent events were noted other than those noted in Note 13, Commitments and Contingencies

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2022
SIGNIFICANT ACCOUNTING POLICIES
SIGNIFICANT ACCOUNTING POLICIES	2. SIGNIFICANT ACCOUNTING POLICIES Recent Accounting Pronouncements In March 2020, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2020-04, Reference Rate Reform (Topic 848) ​ Principles of Consolidation The Company accounts for subsidiary partnerships, joint ventures and other similar entities in which it holds an ownership interest in accordance with the consolidation guidance. The Company first evaluates whether each entity is a variable interest entity (“VIE”). Under the VIE model, the Company consolidates an entity when it has control to direct the activities of the VIE and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. Under the voting model, the Company consolidates an entity when it controls the entity through ownership of a majority voting interest. Real Estate Sales Gain Recognition ​ For sale transactions resulting in a transfer of a controlling financial interest of a property, the Company generally derecognizes the related assets and liabilities from its Consolidated Balance Sheets and records the gain or loss in the period in which the transfer of control occurs. If control of the property has not transferred to the counterparty, the criteria for derecognition are not met and the Company will continue to recognize the related assets and liabilities on its Consolidated Balance Sheets. ​ Sale transactions to entities in which the Company sells a controlling financial interest in a property but retains a noncontrolling interest are accounted for as partial sales. Partial sales resulting in a change in control are accounted for at fair value and a full gain or loss is recognized. Therefore, the Company will record a gain or loss on the partial interest sold, and the initial measurement of our retained interest will be accounted for at fair value. ​ Sales of real estate to joint ventures or other noncontrolled investees are also accounted for at fair value and the Company will record a full gain or loss in the period the property is contributed. ​ To the extent that the Company acquires a controlling financial interest in a property that it previously accounted for as an equity method investment, the Company will not remeasure its previously held interest if the acquisition is treated as an asset acquisition. The Company will include the carrying amount of its previously held equity method interest along with the consideration paid and transaction costs incurred in determining the amounts to allocate to the related assets and liabilities acquired on its Consolidated Balance Sheets. When treated as an asset acquisition, the Company will not recognize a gain or loss on consolidation of a property. ​ Allowance for Credit Losses The Company accounts for allowance for credit losses under the current expected credit loss (“CECL”) impairment model for its financial assets, including trade and other receivables, held-to-maturity debt securities, loans and other financial instruments, and presents the net amount of the financial instrument expected to be collected. The CECL impairment model excludes operating lease receivables. The CECL impairment model requires an estimate of expected credit losses, measured over the contractual life of an instrument, that considers forecasts of future economic conditions in addition to information about past events and current conditions. Based on this model, we analyze the following criteria, as applicable in developing allowances for credit losses: historical loss information, the borrower’s ability to make scheduled payments, the remaining time to maturity, the value of underlying collateral, projected future performance of the borrower and macroeconomic trends. ​ The Company measures credit losses of financial assets on a collective (pool) basis when similar risk characteristics exist. If the Company determines that a financial asset does not share risk characteristics with the Company’s other financial assets, the Company evaluates the financial asset for expected credit losses on an individual basis. Allowance for credit losses are recorded as a direct reduction from an asset’s amortized cost basis. Credit losses and recoveries are recorded in Interest income and other income/(expense), net ​ The Company has made the optional election provided by the standard not to measure allowance for credit losses for accrued interest receivables as the Company writes off any uncollectible accrued interest receivables in a timely manner. The Company periodically evaluates the collectability of its accrued interest receivables. A write-off is recorded when the Company concludes that all or a portion of its accrued interest receivable balance is no longer collectible. ​ Notes Receivable Notes receivable relate to financing arrangements which are typically secured by assets of the borrower that may include real estate assets. Certain of the loans we extend may include characteristics such as options to purchase the project within a specific time window following expected project completion. These characteristics can cause the loans to fall under the definition of a VIE, and thus trigger consolidation consideration. We consider the facts and circumstances pertinent to each loan, including the relative amount of financing we are contributing to the overall project cost, decision making rights or control we hold, and our rights to expected residual gains or our obligations to absorb expected residual losses from the project. If we are deemed to be the primary beneficiary of a VIE due to holding a controlling financial interest, the majority of decision making control, or by other means, consolidation of the VIE would be required. The Company has concluded that it is not the primary beneficiary of the borrowing entities of the existing loans. Additionally, we analyze each loan arrangement that involves real estate development to consider whether the loan qualifies for accounting as a loan or as an investment in a real estate development project. The Company has evaluated its real estate loans, where appropriate, for accounting treatment as loans versus real estate development projects, as required by ASC 310-10. For each loan, the Company has concluded that the characteristics and the facts and circumstances indicate that loan accounting treatment is appropriate. The following table summarizes our Notes receivable, net dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate at ​ Balance Outstanding ​ March 31, March 31, December 31, ​ ​ 2022 ​ 2022 ​ 2021 Note due May 2022 (a) ​ N/A ​ $ — ​ $ 2,760 Note due January 2023 (b) ​ 10.00 % ​ 26,710 ​ ​ 24,235 Notes Receivable ​ ​ ​ ​ 26,710 ​ ​ 26,995 Allowance for credit losses ​ ​ ​ ​ (133) ​ ​ (135) Total notes receivable, net ​ $ 26,577 ​ $ 26,860 (a) The Company previously had a secured note with an unaffiliated third party with an aggregate commitment of $2.8 million. The note was secured by a parcel of land located in Kissimmee, Florida. In March 2022, the unaffiliated third party repaid the $2.8 million secured note in full. (b) The Company has a secured note with an unaffiliated third party with an aggregate commitment of $30.4 million. In March 2022, the terms of this secured note were amended to increase the aggregate commitment from $25.4 million to $30.4 million. Following the March 2022 note amendment, the balance increased to $26.7 million . Interest payments are due monthly. The note is secured by substantially all of the borrower’s assets and matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) January 2023. The Company recognized $0.7 million and $1.9 million of interest income for the notes receivable described above during the three months ended March 31, 2022 and 2021, respectively, none of which was related party interest. Interest income is included in Interest income and other income/(expense), net Comprehensive Income/(Loss) Comprehensive income/(loss), which is defined as the change in equity during each period from transactions and other events and circumstances from nonowner sources, including all changes in equity during a period except for those resulting from investments by or distributions to stockholders, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the three months ended March 31, 2022 and 2021, the Company’s other comprehensive income/(loss) consisted of the gain/(loss) on derivative instruments that are designated as and qualify as cash flow hedges, (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) into earnings, and the allocation of other comprehensive income/(loss) to noncontrolling interests. The (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) is included in Interest expense Derivatives and Hedging Activity, Income Taxes Due to the structure of the Company as a REIT and the nature of the operations for the operating properties, no provision for federal income taxes has been provided for at UDR. Historically, the Company has generally incurred only state and local excise and franchise taxes. UDR has elected for certain consolidated subsidiaries to be treated as taxable REIT subsidiaries (“TRS”). Income taxes for our TRS are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rate is recognized in earnings in the period of the enactment date. The Company’s deferred tax assets/(liabilities) are generally the result of differing depreciable lives on capitalized assets, temporary differences between book and tax basis of assets and liabilities and timing of expense recognition for certain accrued liabilities. As of March 31, 2022 and December 31, 2021, UDR’s net deferred tax asset/(liability) was ($0.8) million and ($0.8) million, respectively, and are recorded in Accounts payable, accrued expenses and other liabilities GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition. The Company recognizes and evaluates its tax positions using a two-step process. First, UDR determines whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. Second, the Company will determine the amount of benefit to recognize and record the amount that is more likely than not to be realized upon ultimate settlement. The Company invests in assets that qualify for federal investment tax credits (“ITC”) through our TRS. An ITC reduces federal income taxes payable when qualifying depreciable property is acquired. The ITC is determined as a percentage of cost of the assets. The Company accounts for ITCs under the deferral method, under which the tax benefit from the ITC is deferred and amortized as a tax benefit into Tax (provision)/benefit, net Accounts payable, accrued expenses and other liabilities UDR had no material unrecognized tax benefit, accrued interest or penalties at March 31, 2022. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2018 through 2020 remain open to examination by tax jurisdictions to which we are subject. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in Tax (provision)/benefit, net ​ Forward Sales Agreements ​ From time to time the Company utilizes forward sales agreements for the future issuance of its common stock. When the Company enters into a forward sales agreement, the contract requires the Company to sell its shares to a counterparty at a predetermined price at a future date. The net sales price and proceeds attained by the Company will be determined on the dates of settlement, with adjustments during the term of the contract for the Company’s anticipated dividends as well as for a daily interest factor that varies with changes in the federal funds rate. The Company generally has the ability to determine the dates and method of settlement (i.e., gross physical settlement, net share settlement or cash settlement), subject to certain conditions and the right of the counterparty to accelerate settlement under certain circumstances. ​ The Company accounts for the shares of common stock reserved for issuance upon settlement as equity in accordance with ASC 815-40, Contracts in Entity's Own Equity ​ The guidance establishes a two-step process for evaluating whether an equity-linked financial instrument is considered indexed to the entity’s own stock, first, evaluating the instrument’s contingent exercise provisions and second, evaluating the instrument’s settlement provisions. When entering into forward sales agreements, we determined that (i) none of the agreement’s exercise contingencies are based on observable markets or indices besides those related to the market for our own stock price; and (ii) none of the settlement provisions preclude the agreements from being indexed to our own stock. ​ Before the issuance of shares of common stock, upon physical or net share settlement of the forward sales agreements, the Company expects that the shares issuable upon settlement of the forward sales agreements will be reflected in its diluted income/(loss) per share calculations using the treasury stock method. Under this method, the number of shares of common stock used in calculating diluted income/(loss) per share is deemed to be increased by the excess, if any, of the number of shares of common stock that would be issued upon full physical settlement of the forward sales agreements over the number of shares of common stock that could be purchased by the Company in the open market (based on the average market price during the period) using the proceeds receivable upon full physical settlement (based on the adjusted forward sale price at the end of the reporting period). When the Company physically or net share settles any forward sales agreement, the delivery of shares of common stock would result in an increase in the number of weighted average common shares outstanding and dilution to basic income/(loss) per share. (See Note 8, Income/(Loss) per Share ​ Impact of COVID-19 Pandemic ​ We continue to monitor the status and respond to the effects of the COVID-19 pandemic and its impact on our business. While the pandemic and related government measures adversely impacted our business in certain prior periods, the extent of the impact generally has decreased. Future developments regarding COVID-19, however, continue to be uncertain and difficult to predict. There can be no assurances that closures or restrictions in response to COVID-19, including due to new variants, will not be imposed in the future or that other developments related to COVID-19 will not adversely affect our business, results of operations, financial condition and cash flows in future periods. ​ During the three months ended March 31, 2022, the Company performed an analysis in accordance with the ASC 842, Leases, guidance to assess the collectibility of its operating lease receivables in light of the COVID-19 pandemic. This analysis included an assessment of collectibility of current and future rents and whether those lease payments were no longer probable of collection. In accordance with the leases guidance, if lease payments are no longer deemed to be probable over the life of the lease contract, we recognize revenue only when cash is received, and all existing contractual operating lease receivables and straight-line lease receivables are reserved. ​ As a result of its analysis, the Company reduced its reserve by approximately $1.3 million for multifamily tenant lease receivables and approximately $1.2 million for retail tenant lease receivables for its wholly-owned communities and communities held by joint ventures for the three months ended March 31, 2022. In aggregate, the reduction in reserve is reflected as a $2.3 million increase to Rental income and a $0.2 million increase to Income/(loss) from unconsolidated entities on the Consolidated Statements of Operations for the three months ended March 31, 2022 . The impact to deferred leasing commissions was not material for the three months ended March 31, 2022. ​ The Company did not recognize any other adjustments to the carrying amounts of assets or asset impairment charges due to the COVID-19 pandemic for the three months ended March 31, 2022 .

REAL ESTATE OWNED

REAL ESTATE OWNED	3 Months Ended
	Mar. 31, 2022
REAL ESTATE OWNED
REAL ESTATE OWNED	3. REAL ESTATE OWNED Real estate assets owned by the Company consist of income producing operating properties, properties under development, land held for future development, and held for disposition properties. As of March 31, 2022, the Company owned and consolidated 160 communities in 13 states plus the District of Columbia totaling 53,503 apartment homes. The following table summarizes the carrying amounts for our real estate owned (at cost) as of March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Land ​ $ 2,325,852 ​ $ 2,342,385 Depreciable property — held and used: ​ ​ ​ Land improvements ​ 242,835 ​ 241,905 Building, improvements, and furniture, fixtures and equipment ​ 11,756,244 ​ 11,717,931 Real estate intangible assets ​ ​ 50,013 ​ ​ 50,013 Under development: ​ ​ Land and land improvements ​ 90,932 ​ 74,399 Building, improvements, and furniture, fixtures and equipment ​ 367,179 ​ 314,170 Real estate owned ​ 14,833,055 ​ 14,740,803 Accumulated depreciation (a) ​ (5,289,853) ​ (5,137,096) Real estate owned, net ​ $ 9,543,202 ​ $ 9,603,707 (a) Accumulated depreciation is inclusive of $10.2 million and $8.8 million of accumulated amortization related to real estate intangible assets as of March 31, 2022 and December 31, 2021, respectively. ​ Acquisitions and Dispositions The Company did not have any acquisitions or dispositions during the three months ended March 31, 2022. ​ Other Activity Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation direct costs of development and redevelopment and capitalized interest, for the three months ended March 31, 2022 and 2021, were $5.4 million and $4.6 million, respectively. Total capitalized interest was $3.2 million and $2.1 million for the three months ended March 31, 2022 and 2021, respectively. As each apartment home in a capital project is completed and becomes available for lease-up, the Company ceases capitalization on the related portion of the costs and depreciation commences over the estimated useful life. We record impairment losses on long-lived assets used in operations when events and circumstances indicate that the assets might be impaired and the undiscounted cash flows estimated to be generated by the future operation and disposition of those assets are less than the net book value of those assets. Our cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. The net book value of impaired assets is reduced to fair value. Our estimates of fair value represent our best estimate based upon Level 3 inputs such as industry trends and reference to market rates and transactions. The Company did not recognize any impairments in the value of its long-lived assets during the three months ended March 31, 2022 and 2021. In connection with the acquisition of certain properties, the Company agreed to pay certain of the tax liabilities of certain contributors if the Company sells one or more of the properties contributed in a taxable transaction prior to the expiration of specified periods of time following the acquisition. The Company may, however, sell, without being required to pay any tax liabilities, any of such properties in a non-taxable transaction, including, but not limited to, a tax-deferred Section 1031 exchange. Further, the Company has agreed to maintain certain debt that may be guaranteed by certain contributors for specified periods of time following the acquisition. The Company, however, has the ability to refinance or repay guaranteed debt or to substitute new debt if the debt and the guaranty continue to satisfy certain conditions.

VARIABLE INTEREST ENTITIES

VARIABLE INTEREST ENTITIES	3 Months Ended
	Mar. 31, 2022
VARIABLE INTEREST ENTITIES
VARIABLE INTEREST ENTITIES	4. VARIABLE INTEREST ENTITIES The Company has determined that the Operating Partnership and DownREIT Partnership are VIEs as the limited partners lack substantive kick-out rights and substantive participating rights. The Company has concluded that it is the primary beneficiary of, and therefore consolidates, the Operating Partnership and DownREIT Partnership based on its role as the sole general partner of the Operating Partnership and DownREIT Partnership. The Company’s role as community manager and its equity interests give us the power to direct the activities that most significantly impact the economic performance and the obligation to absorb potentially significant losses or the right to receive potentially significant benefits of the Operating Partnership and DownREIT Partnership.

JOINT VENTURES AND PARTNERSHIPS

JOINT VENTURES AND PARTNERSHIPS	3 Months Ended
	Mar. 31, 2022
JOINT VENTURES AND PARTNERSHIPS
JOINT VENTURES AND PARTNERSHIPS	5. JOINT VENTURES AND PARTNERSHIPS UDR has entered into joint ventures and partnerships with unrelated third parties to own, operate, acquire, renovate, develop, redevelop, dispose of, and manage real estate assets that are either consolidated and included in Real estate owned Investment in and advances to unconsolidated joint ventures, net UDR’s joint ventures and partnerships are funded with a combination of debt and equity. Our losses are typically limited to our investment and except as noted below, the Company does not guarantee any debt, capital payout or other obligations associated with our joint ventures and partnerships. The Company recognizes earnings or losses from our investments in unconsolidated joint ventures and partnerships consisting of our proportionate share of the net earnings or losses of the joint ventures and partnerships. In addition, we may earn fees for providing management services for the communities held by the unconsolidated joint ventures and partnerships. The following table summarizes the Company’s investment in and advances to unconsolidated joint ventures and partnerships, net, which are accounted for under the equity method of accounting as of March 31, 2022 and December 31, 2021 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Number of ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ Apartment ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ ​ ​ Communities ​ Homes ​ Investment at ​ UDR’s Ownership Interest ​ ​ Three Months Ended ​ Location of March 31, March 31, March 31, December 31, ​ March 31, ​ December 31, ​ March 31, Joint Ventures Properties 2022 2022 2022 2021 ​ 2022 ​ 2021 ​ 2022 2021 Operating: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ UDR/MetLife I ​ Los Angeles, CA ​ 1 ​ 150 ​ $ 22,936 ​ $ 23,880 ​ 50.0 % ​ 50.0 % ​ $ (625) ​ $ (475) UDR/MetLife II Various 7 1,250 ​ 179,223 ​ 181,023 ​ 50.0 % ​ 50.0 % ​ ​ 100 ​ ​ (2,684) Other UDR/MetLife Joint Ventures (a) Various 5 1,437 ​ 62,233 ​ 66,012 ​ 50.6 % ​ 50.6 % ​ ​ (2,113) ​ ​ (3,382) Investment in and advances to unconsolidated joint ventures, net, before preferred equity investments and real estate technology investments ​ $ 264,392 ​ $ 270,915 ​ ​ ​ ​ $ (2,638) ​ $ (6,541) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment at ​ Three Months Ended Developer Capital Program ​ ​ Years To ​ UDR March 31, December 31, ​ March 31, and Real Estate Technology Investments (b) Location Rate Maturity ​ Commitment (c) 2022 2021 2022 2021 Preferred equity investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ 1532 Harrison ​ San Francisco, CA ​ 11.0 % 0.2 ​ $ 24,645 ​ $ 34,945 ​ $ 35,248 ​ $ (6) ​ $ 929 Junction ​ Santa Monica, CA ​ 12.0 % 0.3 ​ ​ 8,800 ​ ​ 13,577 ​ ​ 13,183 ​ ​ 394 ​ ​ 350 1200 Broadway (d) (e) ​ Nashville, TN ​ N/A ​ — ​ ​ — ​ ​ — ​ ​ 61,326 ​ ​ 11,893 ​ ​ 1,372 1300 Fairmount (e) ​ Philadelphia, PA ​ 8.5 % 1.4 ​ ​ 51,393 ​ ​ 66,146 ​ ​ 64,780 ​ ​ 1,366 ​ ​ 1,255 Modera Lake Merritt (e) ​ Oakland, CA ​ 9.0 % 2.0 ​ ​ 27,250 ​ ​ 34,584 ​ ​ 33,828 ​ ​ 756 ​ ​ 691 Thousand Oaks (e) ​ Thousand Oaks, CA ​ 9.0 % 2.9 ​ ​ 20,059 ​ ​ 23,272 ​ ​ 22,764 ​ ​ 508 ​ ​ 438 Vernon Boulevard (e) ​ Queens, NY ​ 13.0 % 3.3 ​ ​ 40,000 ​ ​ 49,771 ​ ​ 48,210 ​ ​ 1,561 ​ ​ 1,372 Makers Rise (e) ​ Herndon, VA ​ 9.0 % 3.8 ​ ​ 30,208 ​ ​ 31,583 ​ ​ 22,828 ​ ​ 644 ​ ​ 96 121 at Watters (e) ​ Allen, TX ​ 9.0 % 3.9 ​ ​ 19,843 ​ ​ 21,045 ​ ​ 14,134 ​ ​ 394 ​ ​ 2 Infield Phase I ​ Kissimmee, FL ​ 14.0 % 2.1 ​ ​ 16,044 ​ ​ 7,567 ​ ​ — ​ ​ 86 ​ ​ — Upton Place ​ Washington, D.C. ​ 9.7 % 5.7 ​ ​ 52,163 ​ ​ 37,232 ​ ​ 29,566 ​ ​ 676 ​ ​ — Meetinghouse (f) ​ Portland, OR ​ 8.25 % 4.9 ​ ​ 11,600 ​ ​ 11,603 ​ ​ — ​ ​ 3 ​ ​ — Real estate technology investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ RETV I (g) ​ N/A ​ N/A ​ N/A ​ ​ 18,000 ​ ​ 51,912 ​ ​ 71,464 ​ ​ (10,111) ​ ​ 2,051 RETV II ​ N/A ​ N/A ​ N/A ​ ​ 18,000 ​ ​ 7,818 ​ ​ 8,130 ​ ​ (114) ​ ​ (101) RET Strategic Fund (h) ​ N/A ​ N/A ​ N/A ​ ​ 25,000 ​ ​ 7,517 ​ ​ — ​ ​ — ​ ​ — Total Preferred Equity Investments and Real Estate Technology Investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 398,572 ​ ​ 425,461 ​ ​ 8,050 ​ ​ 8,455 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sold joint ventures and other investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ — ​ ​ — ​ ​ — ​ ​ 3,008 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Joint Ventures and Developer Capital Program and Real Estate Technology Investments, net (a) ​ ​ ​ ​ $ 662,964 ​ $ 696,376 ​ $ 5,412 $ 4,922 (a) As of March 31, 2022 and December 31, 2021, the Company’s negative investment in 13 th and Market Properties LLC of $6.4 million and $6.1 million, respectively, is included in Other UDR/MetLife Joint Ventures in the table above and recorded in Accounts payable, accrued expenses, and other liabilities on the Consolidated Balance Sheet. (b) The Developer Capital Program is the program through which the Company makes investments, including preferred equity investments, mezzanine loans or other structured investments that may receive a fixed yield on the investment and may include provisions pursuant to which the Company participates in the increase in value of the property upon monetization of the applicable property. (c) Represents UDR’s maximum funding commitment only and therefore excludes other activity such as income from investments. (d) In J anuary 2022, the joint venture sold its community, a 313 apartment home operating community located in Nashville, Tennessee, for a sales price of approximately $294.0 million. As a result, the Company recorded variable upside participation on the sale of approximately $10.6 million, net of associated costs. (e) The Company’s preferred equity investment receives a variable percentage of the value created from the project upon a capital or liquidating event. (f) In March 2022, the Company entered into a joint venture agreement with an unaffiliated joint venture partner to operate a 232 apartment home community in Portland, Oregon. The Company’s preferred equity investment of $11.6 million earns a preferred return of 8.25% per annum. The unaffiliated joint venture partner is the managing member of the joint venture. The Company has concluded that it does not control the joint venture and accounts for it under the equity method of accounting . (g) The Company recognized $(10.1) million and $2.1 million of investment income/(loss) from RETV I for the three months ended March 31, 2022 and 2021, respectively, which primarily related to unrealized gains/(losses) from one portfolio investment held by RETV I, SmartRent, Inc. (“SmartRent”). In 2021, SmartRent, a provider of smart home automation solutions, went public through a merger with a publicly traded special purpose acquisition company. As a result, SmartRent began trading on the New York Stock Exchange under the ticker symbol “SMRT.” Due to the merger, all shares of SmartRent that RETV I held were converted to publicly traded SmartRent shares based on a pre-determined conversion factor. Following the merger and stock conversion, RETV I began recording its investment in SmartRent based on the share price at the end of the applicable reporting period. (h) In January 2022, the Company entered into a real estate technology investment as a limited partner, for a total commitment of $25.0 million. The Company funded $7.5 million to the limited partnership at closing. The Company has concluded that it does not control the limited partnership and accounts for it under the equity method of accounting. As of March 31, 2022 and December 31, 2021, the Company had deferred fees of $7.7 million and $8.7 million, respectively, which will be recognized through earnings over the weighted average life of the related properties, upon the disposition of the properties to a third party, or upon completion of certain development obligations. The Company recognized management fees of $1.1 million and $ 1.6 million for the three months ended March 31, 2022 and 2021, respectively, for management of the communities held by the joint ventures and partnerships. The management fees are included in Joint venture management and other fees on the Consolidated Statements of Operations. The Company may, in the future, make additional capital contributions to certain of our joint ventures and partnerships should additional capital contributions be necessary to fund acquisitions or operations. We consider various factors to determine if a decrease in the value of our Investment in and advances to unconsolidated joint ventures, net Combined summary balance sheets relating to the unconsolidated joint ventures’ and partnerships’ (not just our proportionate share) are presented below as of March 31, 2022 and December 31, 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2022 2021 Total real estate, net $ 2,121,264 $ 2,043,158 Real estate assets held for sale ​ — ​ 168,668 Investments, at fair value ​ ​ 383,143 ​ ​ 460,241 Cash and cash equivalents ​ 31,328 ​ 22,891 Other assets ​ ​ 24,494 ​ 28,948 Total assets $ 2,560,229 $ 2,723,906 ​ ​ ​ ​ ​ ​ ​ Third party debt, net ​ $ 1,245,610 ​ $ 1,215,918 Liabilities held for sale ​ — ​ 106,990 Accounts payable and accrued liabilities ​ ​ 75,487 ​ ​ 51,689 Total liabilities ​ 1,321,097 ​ 1,374,597 Total equity $ 1,239,132 $ 1,349,309 ​ Combined summary financial information relating to the unconsolidated joint ventures’ and partnerships’ operations (not just our proportionate share) is presented below for the three months ended March 31, 2022 and 2021 ( dollars in thousands : ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ 2022 2021 Total revenues $ 37,169 $ 32,137 Property operating expenses ​ 17,930 ​ 17,110 Real estate depreciation and amortization ​ 17,820 ​ 16,453 Gain/(loss) on sale of property ​ ​ 127,542 ​ ​ 34,757 Operating income/(loss) ​ 128,961 ​ ​ 33,331 Interest expense ​ (8,132) ​ (12,134) Net realized gain/(loss) on held investments ​ ​ 6,304 ​ ​ 2,494 Net unrealized gain/(loss) on held investments ​ ​ (21,492) ​ ​ 5,994 Other income/(loss) ​ ​ (224) ​ ​ (1,657) Net income/(loss) $ 105,417 $ 28,028 ​

LEASES

LEASES	3 Months Ended
	Mar. 31, 2022
LEASES
LEASES	6. LEASES Lessee - Ground Leases UDR has six communities that are subject to ground leases, under which UDR is the lessee, that expire between 2043 and 2103, inclusive of extension options we are reasonably certain will be exercised. All of these leases are classified as operating leases through the lease term expiration based on our election of the practical expedient provided by the leasing standard. Rental expense for lease payments related to operating leases is recognized on a straight-line basis over the remaining lease term. We currently do not hold any finance leases. The Company also elected the short-term lease exception provided by the leasing standard and therefore only recognizes right-of-use assets and lease liabilities for leases with a term greater than one year. No leases qualified for the short-term lease exception during the three months ended March 31, 2022 and 2021. As of March 31, 2022 and December 31, 2021, the Operating lease right-of-use assets Operating lease liabilities Operating lease right-of-use assets Operating lease liabilities As the discount rate implicit in the leases was not readily determinable, we determined the discount rate for these leases utilizing the Company’s incremental borrowing rate at a portfolio level, adjusted for the remaining lease term, and the form of underlying collateral. The weighted average remaining lease term for these leases was 43.1 years and 43.2 years at March 31, 2022 and December 31, 2021, respectively, and the weighted average discount rate was 5.0% at both March 31, 2022 and December 31, 2021. Future minimum lease payments and total operating lease liabilities from our ground leases as of March 31, 2022 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Ground Leases 2022 ​ $ 9,331 2023 ​ ​ 12,442 2024 ​ ​ 12,442 2025 ​ ​ 12,442 2026 ​ ​ 12,442 Thereafter ​ ​ 430,337 Total future minimum lease payments (undiscounted) ​ ​ 489,436 Difference between future undiscounted cash flows and discounted cash flows ​ ​ (297,747) Total operating lease liabilities (discounted) ​ $ 191,689 ​ For purposes of recognizing our ground lease contracts, the Company uses the minimum lease payments, if stated in the agreement. For ground lease agreements where there is a rent reset provision based on a change in an index or a rate (i.e., changes in fair market rental rates or changes in the consumer price index) but that does not include a specified minimum lease payment, the Company uses the current rent over the remainder of the lease term. If there is a contingency upon which some or all of the variable lease payments that will be paid over the remainder of the lease term are based, which is resolved such that those payments now meet the definition of lease payments, the Company will remeasure the right-of-use asset and lease liability on the reset date. The components of operating lease expenses were as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2022 ​ 2021 Lease expense: ​ ​ ​ ​ ​ ​ Contractual lease expense ​ $ 3,311 ​ $ 3,230 Variable lease expense (a) ​ ​ 26 ​ ​ 29 Total operating lease expense (b)(c) ​ $ 3,337 ​ $ 3,259 (a) Variable lease expense includes adjustments such as changes in the consumer price index and payments based on a percentage of a community’s income. (b) Lease expense is reported within the line item Other operating expenses on the Consolidated Statements of Operations. (c) For the three months ended March 31, 2022, Operating lease right-of-use assets and Operating lease liabilities amortized by $0.9 million and $0.8 million, respectively. For the three months ended March 31, 2021, Operating lease right-of-use assets and Operating lease liabilities amortized by $0.8 million and $0.8 million, respectively. Due to the net impact of the amortization, the Company recorded $0.1 million and less than $0.1 million of total operating lease expense during the three months ended March 31, 2022 and 2021, respectively. ​ Lessor - Apartment Home, Retail and Commercial Space Leases ​ UDR’s communities and retail and commercial space are leased to tenants under operating leases. As of March 31, 2022, our apartment home leases generally have initial terms of 12 months or less. As of March 31, 2022, our retail and commercial space leases generally have initial terms of between 5 and 15 years and represent approximately 1% to 2% of our total lease revenue. Our apartment home leases are generally renewable at the end of the lease term, subject to potential increases in rental rates, and our retail and commercial space leases generally have renewal options, subject to associated increases in rental rates due to market based or fixed price renewal options and certain other conditions. (See Note 14, Reportable Segments ​ Future minimum lease payments from our retail and commercial leases as of March 31, 2022 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Retail and Commercial Leases 2022 ​ $ 18,504 2023 ​ ​ 24,186 2024 ​ ​ 22,012 2025 ​ ​ 18,834 2026 ​ ​ 16,028 Thereafter ​ ​ 68,924 Total future minimum lease payments (a) ​ $ 168,488 (a) Certain of our leases with retail and commercial tenants provide for the payment by the lessee of additional variable rent based on a percentage of the tenant’s revenue. The amounts shown in the table above do not include these variable percentage rents. The Company recorded variable percentage rents of $0.3 million and $0.1 million during the three months ended March 31, 2022 and 2021, respectively.

SECURED AND UNSECURED DEBT, NET

SECURED AND UNSECURED DEBT, NET	3 Months Ended
	Mar. 31, 2022
SECURED AND UNSECURED DEBT, NET
SECURED AND UNSECURED DEBT, NET	7. SECURED AND UNSECURED DEBT, NET The following is a summary of our secured and unsecured debt at March 31, 2022 and December 31, 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal Outstanding ​ As of March 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Average ​ Number of ​ ​ March 31, ​ December 31, ​ Interest ​ Years to ​ Communities ​ 2022 2021 Rate Maturity Encumbered Secured Debt: ​ ​ ​ ​ ​ ​ ​ Fixed Rate Debt ​ ​ Mortgage notes payable (a) ​ $ 1,006,482 ​ $ 1,006,762 3.42 % 6.2 14 Deferred financing costs and other non-cash adjustments (b) ​ 22,686 ​ 23,678 Total fixed rate secured debt, net ​ 1,029,168 ​ 1,030,440 3.42 % 6.2 14 Variable Rate Debt ​ ​ Tax-exempt secured notes payable (c) ​ 27,000 ​ 27,000 0.87 % 10.0 1 Deferred financing costs ​ (58) ​ (60) Total variable rate secured debt, net ​ 26,942 ​ 26,940 0.87 % 10.0 1 Total Secured Debt, net ​ 1,056,110 ​ 1,057,380 3.35 % 6.3 15 Unsecured Debt: ​ ​ Variable Rate Debt ​ ​ Borrowings outstanding under unsecured credit facility due January 2026 (d) (m) ​ — ​ — — % 3.8 Borrowings outstanding under unsecured commercial paper program due April 2022 (e) (m) ​ ​ 280,000 ​ ​ 220,000 ​ 0.77 % 0.1 ​ ​ Borrowings outstanding under unsecured working capital credit facility due January 2024 ​ 37,194 ​ 29,546 1.23 % 1.8 Term Loan due January 2027 (d) (m) ​ 35,000 ​ 35,000 1.08 % 4.8 Fixed Rate Debt ​ ​ Term Loan due January 2027 (d) (m) ​ ​ 315,000 ​ 315,000 1.02 % 4.8 ​ ​ 8.50% Debentures due September 2024 ​ 15,644 ​ 15,644 8.50 % 2.5 2.95% Medium-Term Notes due September 2026 (g) (m) ​ 300,000 ​ 300,000 2.89 % 4.4 3.50% Medium-Term Notes due July 2027 (net of discounts of $370 and $388, respectively) (h) (m) ​ ​ 299,630 ​ ​ 299,612 ​ 4.03 % 5.3 ​ ​ 3.50% Medium-Term Notes due January 2028 (net of discounts of $689 and $717, respectively) (m) ​ ​ 299,311 ​ ​ 299,283 ​ 3.50 % 5.8 ​ ​ 4.40% Medium-Term Notes due January 2029 (net of discounts of $4 and $4, respectively) (i) (m) ​ ​ 299,996 ​ ​ 299,996 ​ 4.27 % 6.8 ​ ​ 3.20% Medium-Term Notes due January 2030 (net of premiums of $10,697 and $11,040, respectively) (j) (m) ​ ​ 610,697 ​ ​ 611,040 ​ 3.32 % 7.8 ​ ​ 3.00% Medium-Term Notes due August 2031 (net of premiums/discounts of $11,200 and $11,498, respectively) (k) (m) ​ ​ 611,200 ​ ​ 611,498 ​ 3.01 % 9.4 ​ ​ 2.10% Medium-Term Notes due August 2032 (net of discounts of $364 and $373, respectively) (m) ​ ​ 399,636 ​ ​ 399,627 ​ 2.10 % 10.3 ​ ​ 1.90% Medium-Term Notes due March 2033 (net of discounts of $1,321 and $1,351, respectively) (m) ​ ​ 348,679 ​ ​ 348,649 ​ 1.90 % 10.9 ​ ​ 2.10% Medium-Term Notes due June 2033 (net of discounts of $1,115 and $1,140, respectively) (m) ​ ​ 298,885 ​ ​ 298,860 ​ 2.10 % 11.2 ​ ​ 3.10% Medium-Term Notes due November 2034 (net of discounts of $1,111 and $1,133, respectively) (l) (m) ​ ​ 298,889 ​ ​ 298,867 ​ 3.13 % 12.6 ​ ​ Other ​ 7 ​ 7 Deferred financing costs ​ (26,868) ​ (27,222) Total Unsecured Debt, net ​ 4,422,900 ​ 4,355,407 2.71 % 7.7 Total Debt, net ​ $ 5,479,010 ​ $ 5,412,787 2.80 % 7.4 ​ For purposes of classification of the above table, variable rate debt with a derivative financial instrument designated as a cash flow hedge is deemed as fixed rate debt due to the Company having effectively established a fixed interest rate for the underlying debt instrument. Our secured debt instruments generally feature either monthly interest and principal or monthly interest-only payments with balloon payments due at maturity. As of March 31, 2022, secured debt encumbered $1.7 billion or 11.7% of UDR’s total real estate owned based upon gross book value ($13.1 billion or 88.3% of UDR’s real estate owned based on gross book value is unencumbered). (a) The Company will from time to time acquire properties subject to fixed rate debt instruments. In those situations, the Company records the debt at its estimated fair value and amortizes any difference between the fair value and par value to interest expense over the term of the underlying debt instrument. (b) Interest expense ​ (c) (d) six-month extension options, subject to certain conditions. The Term Loan has a scheduled maturity date of January 31, 2027. Based on the Company’s current credit rating, the Revolving Credit Facility has an interest rate equal to LIBOR plus a margin of 77.5 basis points and a facility fee of 15 basis points, and the Term Loan has an interest rate equal to LIBOR plus a margin of 85 basis points. Depending on the Company’s credit rating, the margin under the Revolving Credit Facility ranges from 70 to 140 basis points, the facility fee ranges from 10 to 30 basis points, and the margin under the Term Loan ranges from 75 to 160 basis points. F urther, the Credit Agreement includes sustainability adjustments pursuant to which the applicable margin for the Revolving Credit Facility and the Term Loan may be reduced by up to two basis points after September 15, 2022 contingent upon the Company receiving green building certifications. In November 2020, the Company entered into three interest rate swaps, which became effective in January 2021, to hedge against interest rate risk on the Term Loan until July 2022. The all-in weighted average interest rate, inclusive of the impact of the interest rate swaps, was 1.02% . ​ The Credit Agreement contains customary representations and warranties and financial and other affirmative and negative covenants. The Credit Agreement also includes customary events of default, in certain cases subject to customary periods to cure. The occurrence of an event of default, following the applicable cure period, would permit the lenders to, among other things, declare the unpaid principal, accrued and unpaid interest and all other amounts payable under the Credit Agreement to be immediately due and payable. The following is a summary of short-term bank borrowings under the Revolving Credit Facility at March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 2021 ​ Total revolving credit facility ​ $ 1,300,000 ​ $ 1,300,000 ​ Borrowings outstanding at end of period (1) ​ — ​ — ​ Weighted average daily borrowings during the period ended ​ — ​ 13,068 ​ Maximum daily borrowings during the period ended ​ — ​ 305,000 ​ Weighted average interest rate during the period ended ​ — % 0.9 % Interest rate at end of the period ​ — % — % (1) Excludes $2.6 million and $2.6 million of letters of credit at March 31, 2022 and December 31, 2021, respectively . (e) The following is a summary of short-term bank borrowings under the unsecured commercial paper program at March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Total unsecured commercial paper program $ 700,000 ​ $ 700,000 ​ Borrowings outstanding at end of period ​ 280,000 ​ 220,000 ​ Weighted average daily borrowings during the period ended ​ 280,722 ​ 419,563 ​ Maximum daily borrowings during the period ended ​ 410,000 ​ 700,000 ​ Weighted average interest rate during the period ended ​ 0.4 % 0.2 % Interest rate at end of the period ​ 0.8 % 0.3 % ​ (f) The following is a summary of short-term bank borrowings under the Working Capital Credit Facility at March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Total working capital credit facility ​ $ 75,000 ​ $ 75,000 ​ Borrowings outstanding at end of period ​ 37,194 ​ 29,546 ​ Weighted average daily borrowings during the period ended ​ 11,315 ​ 10,473 ​ Maximum daily borrowings during the period ended ​ 39,533 ​ 46,038 ​ Weighted average interest rate during the period ended ​ 1.0 % 0.9 % Interest rate at end of the period ​ 1.2 % 0.9 % ​ (g) (h) (i) (j) The all-in weighted average interest rate, inclusive of the impact of the forward starting swaps and treasury locks, was 3.32% . (k) (l) . (m) The aggregate maturities, including amortizing principal payments on secured and unsecured debt, of total debt for the next ten calendar years subsequent to March 31, 2022 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Fixed Total Variable Total Total Total Year ​ Secured Debt ​ Secured Debt ​ Secured Debt ​ Unsecured Debt ​ Debt 2022 ​ $ 860 ​ $ — ​ $ 860 ​ $ 280,000 (a) $ 280,860 2023 ​ ​ 1,242 ​ ​ — ​ ​ 1,242 ​ ​ — ​ ​ 1,242 2024 ​ 96,747 ​ — ​ 96,747 ​ 52,838 ​ 149,585 2025 ​ 174,793 ​ — ​ 174,793 ​ — ​ 174,793 2026 ​ 52,744 ​ — ​ 52,744 ​ 300,000 ​ 352,744 2027 ​ 2,860 ​ — ​ 2,860 ​ 650,000 ​ 652,860 2028 ​ 162,310 ​ — ​ 162,310 ​ 300,000 ​ 462,310 2029 ​ 191,986 ​ — ​ 191,986 ​ 300,000 ​ 491,986 2030 ​ 162,010 ​ — ​ 162,010 ​ 600,000 ​ 762,010 2031 ​ 160,930 ​ — ​ 160,930 ​ 600,000 ​ 760,930 Thereafter ​ — ​ 27,000 ​ 27,000 ​ 1,350,000 ​ 1,377,000 Subtotal ​ 1,006,482 ​ 27,000 ​ 1,033,482 ​ 4,432,838 ​ 5,466,320 Non-cash (b) ​ 22,686 ​ (58) ​ 22,628 ​ (9,938) ​ 12,690 Total ​ $ 1,029,168 ​ $ 26,942 ​ $ 1,056,110 ​ $ 4,422,900 ​ $ 5,479,010 (a) All unsecured debt due in the remainder of 2022 is related to the Company’s commercial paper program. (b) Includes the unamortized balance of fair market value adjustments, premiums/discounts and deferred financing costs . The Company amortized $0.9 million and $1.2 million, respectively, during the three months ended March 31, 2022 and 2021, of deferred financing costs into Interest expense. We were in compliance with the covenants of our debt instruments at March 31, 2022.

INCOME (LOSS) PER SHARE

INCOME (LOSS) PER SHARE	3 Months Ended
	Mar. 31, 2022
INCOME/(LOSS) PER SHARE
INCOME/(LOSS) PER SHARE	8. INCOME/(LOSS) PER SHARE The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ 2022 2021 ​ Numerator for income/(loss) per share: ​ ​ ​ ​ ​ ​ Net income/(loss) ​ $ 14,603 ​ $ 3,274 ​ Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (879) ​ (154) ​ Net (income)/loss attributable to noncontrolling interests ​ (19) ​ (16) ​ Net income/(loss) attributable to UDR, Inc. ​ 13,705 ​ 3,104 ​ Distributions to preferred stockholders — Series E (Convertible) ​ (1,092) ​ (1,056) ​ Income/(loss) attributable to common stockholders - basic and diluted ​ $ 12,613 ​ $ 2,048 ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator for income/(loss) per share: ​ ​ ​ Weighted average common shares outstanding ​ 318,293 ​ 296,800 ​ Non-vested restricted stock awards ​ (284) ​ (263) ​ Denominator for basic income/(loss) per share ​ 318,009 ​ 296,537 ​ Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, unvested restricted stock and shares issuable upon settlement of forward sales agreements ​ 1,671 ​ 489 ​ Denominator for diluted income/(loss) per share ​ 319,680 ​ 297,026 ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) per weighted average common share: ​ ​ ​ Basic ​ $ 0.04 ​ $ 0.01 ​ Diluted ​ $ 0.04 ​ $ 0.01 ​ ​ Basic income/(loss) per common share is computed based upon the weighted average number of common shares outstanding. Diluted income/(loss) per common share is computed based upon the weighted average number of common shares outstanding plus the common shares issuable from the assumed conversion of the OP Units and DownREIT Units, convertible preferred stock, stock options, unvested long-term incentive plan units (“LTIP Units”), performance units, unvested restricted stock and continuous equity program forward sales agreements. Only those instruments having a dilutive impact on our basic income/(loss) per share are included in diluted income/(loss) per share during the periods. For the three months ended March 31, 2022 and 2021, the effect of the conversion of the OP Units, DownREIT Units and the Company’s Series E preferred stock was not dilutive and therefore not included in the above calculation. In July 2021, the Company entered into an ATM sales agreement under which the Company may offer and sell up to 20.0 million shares of its common stock, from time to time, to or through its sales agents and may enter into separate forward sales agreements to or through its forward purchasers. Upon entering into the ATM sales agreement, the Company simultaneously terminated the sales agreement for its prior at-the-market equity offering program, which was entered into in July 2017. During the three months ended March 31, 2022, the Company did not sell any shares of common stock through its ATM program. As of March 31, 2022, we had 18.4 million shares of common stock available for future issuance under the ATM program, including an aggregate of 4.4 million shares subject to the forward sales agreements described below. In connection with any forward sales agreement under the Company’s ATM program, the relevant forward purchasers will borrow from third parties and, through the relevant sales agent, acting in its role as forward seller, sell a number of shares of the Company’s common stock equal to the number of shares underlying the agreement. The Company does not initially receive any proceeds from any sale of borrowed shares by the forward seller. ​ As of March 31, 2022, the Company had a total of 4.4 million shares of common stock subject to forward sales agreements under its ATM program that had not been settled, which have a weighted average initial forward price per share of $53.72 agreement. The final dates by which the shares sold under the forward sales agreements under the ATM programs must be settled range between August 1, 2022 and September 14, 2022. ​ In March 2022, in connection with an underwritten public offering, the Company entered into forward sale agreements to sell 7.0 million shares of its common stock at an initial forward price per share of $57.565. The actual forward price per share to be received by the Company upon settlement will be determined on the applicable settlement date based on adjustments made to the initial forward price to reflect the then-current federal funds rate and the amount of dividends paid to holders of UDR common stock over the term of the forward sales agreements. As of March 31, 2022, no shares under the forward sale agreements have been settled. The final date by which shares sold under the forward sale agreements must be settled is March 30, 2023. ​ The Company generally has the ability to determine the dates and method of settlement (i.e., gross physical settlement, net share settlement or cash settlement), subject to certain conditions and the right of the counterparty to accelerate settlement under certain circumstances. The Company currently expects to fully physically settle each forward sales agreement with the relevant forward purchaser on one or more dates specified by the Company on or prior to the maturity date of that particular forward sales agreement, in which case the Company expects to receive aggregate net cash proceeds at settlement equal to the number of shares underlying the particular forward sales agreement multiplied by the relevant forward sale price. However, subject to certain exceptions, the Company may also elect, in its discretion, to cash settle or net share settle a particular forward sales agreement, in which case the Company may not receive any proceeds (in the case of cash settlement) or will not receive any proceeds (in the case of net share settlement), and the Company may owe cash (in the case of cash settlement) or shares of UDR common stock (in the case of net share settlement) to the relevant forward purchaser. ​ The following table sets forth the additional shares of common stock outstanding, by equity instrument, if converted to common stock for each of the three months ended March 31, 2022 and 2021 (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ ​ 2022 ​ 2021 ​ OP/DownREIT Units 21,534 22,398 Convertible preferred stock 2,918 2,918 Unvested LTIP Units and unvested restricted stock 1,671 489 ​

NONCONTROLLING INTERESTS

NONCONTROLLING INTERESTS	3 Months Ended
	Mar. 31, 2022
NONCONTROLLING INTERESTS
NONCONTROLLING INTERESTS	9. NONCONTROLLING INTERESTS Redeemable Noncontrolling Interests in the Operating Partnership and DownREIT Partnership Interests in the Operating Partnership and the DownREIT Partnership held by limited partners are represented by OP Units and DownREIT Units, respectively. The income is allocated to holders of OP Units/DownREIT Units based upon net income attributable to common stockholders and the weighted average number of OP Units/DownREIT Units outstanding to total common shares plus OP Units/DownREIT Units outstanding during the period. Capital contributions, distributions, and profits and losses are allocated to noncontrolling interests in accordance with the terms of the partnership agreements of the Operating Partnership and the DownREIT Partnership. Limited partners of the Operating Partnership and the DownREIT Partnership have the right to require such partnership to redeem all or a portion of the OP Units/DownREIT Units held by the limited partner at a redemption price equal to and in the form of the Cash Amount (as defined in the partnership agreement of the Operating Partnership or the DownREIT Partnership, as applicable), provided that such OP Units/DownREIT Units have been outstanding for at least one year, subject to certain exceptions. UDR, as the general partner of the Operating Partnership and the DownREIT Partnership may, in its sole discretion, purchase the OP Units/DownREIT Units by paying to the limited partner either the Cash Amount or the REIT Share Amount (generally one share of common stock of the Company for each OP Unit/DownREIT Unit), as defined in the partnership agreement of the Operating Partnership or the DownREIT Partnership, as applicable. Accordingly, the Company records the OP Units/DownREIT Units outside of permanent equity and reports the OP Units/DownREIT Units at their redemption value using the Company’s stock price at each balance sheet date. The following table sets forth redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership for the following period ( dollars in thousands ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, December 31, 2021 $ 1,299,442 ​ Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (43,747) ​ Conversion of OP Units/DownREIT Units to Common Stock or Cash ​ (23,944) ​ Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ 879 ​ Distributions to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (8,383) ​ Redeemable Long-Term Incentive Plan Units ​ ​ 37,383 ​ Allocation of other comprehensive income/(loss) ​ 514 ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, March 31, 2022 ​ $ 1,262,144 ​ ​ Noncontrolling Interests Noncontrolling interests represent interests of unrelated partners in certain consolidated affiliates, and are presented as part of equity on the Consolidated Balance Sheets since these interests are not redeemable. Net (income)/loss attributable to noncontrolling interests

FAIR VALUE OF DERIVATIVES AND F

FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS	3 Months Ended
	Mar. 31, 2022
FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS
FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS	10. FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS Fair value is based on the price that would be received to sell an asset or the exit price that would be paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three-level valuation hierarchy prioritizes observable and unobservable inputs used to measure fair value. The fair value hierarchy consists of three broad levels, which are described below: ● Level 1 — Quoted prices in active markets for identical assets or liabilities that the entity has the ability to access. ● Level 2 — Observable inputs other than prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated with observable market data. ● Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs. The estimated fair values of the Company’s financial instruments either recorded or disclosed on a recurring basis as of March 31, 2022 and December 31, 2021, are summarized as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at March 31, 2022, Using ​ ​ Total ​ ​ ​ Quoted ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ Prices in ​ ​ ​ ​ ​ ​ Amount in ​ ​ ​ Active ​ ​ ​ ​ ​ ​ ​ Statement of ​ ​ ​ ​ Markets ​ Significant ​ ​ ​ ​ ​ Financial ​ Fair Value ​ for Identical ​ Other ​ Significant ​ ​ Position at ​ Estimate at ​ Assets or ​ Observable ​ Unobservable ​ ​ March 31, ​ March 31, ​ Liabilities ​ Inputs ​ Inputs ​ ​ 2022 (a) ​ 2022 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 26,577 ​ $ 26,818 ​ $ — ​ $ — ​ $ 26,818 Equity securities (c) ​ ​ 7,336 ​ ​ 7,336 ​ ​ 7,336 ​ ​ — ​ ​ — Derivatives - Interest rate contracts (d) ​ 10,488 ​ 10,488 ​ — ​ 10,488 ​ — Total assets ​ $ 44,401 ​ $ 44,642 ​ $ 7,336 ​ $ 10,488 ​ $ 26,818 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,032,370 ​ $ 978,793 ​ $ — ​ $ — ​ $ 978,793 Secured debt instruments - variable rate: (e) ​ ​ ​ ​ ​ ​ Tax-exempt secured notes payable ​ 27,000 ​ 27,000 ​ — ​ — ​ 27,000 Unsecured debt instruments: (e) ​ ​ ​ ​ ​ ​ Working capital credit facility ​ ​ 37,194 ​ ​ 37,194 ​ ​ — ​ ​ — ​ ​ 37,194 Commercial paper program ​ ​ 280,000 ​ ​ 280,000 ​ ​ — ​ ​ — ​ ​ 280,000 Unsecured notes ​ ​ 4,132,574 ​ ​ 3,876,882 ​ ​ — ​ ​ — ​ ​ 3,876,882 Total liabilities ​ $ 5,509,138 ​ $ 5,199,869 ​ $ — ​ $ — ​ $ 5,199,869 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 1,262,144 ​ $ 1,262,144 ​ $ — ​ $ 1,262,144 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at December 31, 2021, Using ​ ​ Total ​ ​ ​ Quoted ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ Prices in ​ ​ ​ ​ ​ ​ Amount in ​ ​ ​ Active ​ ​ ​ ​ ​ ​ Statement of ​ ​ ​ Markets ​ Significant ​ ​ ​ ​ Financial ​ Fair Value ​ for Identical ​ Other ​ Significant ​ ​ Position at ​ Estimate at ​ Assets or ​ Observable ​ Unobservable ​ ​ December 31, ​ December 31, ​ Liabilities ​ Inputs ​ Inputs ​ 2021 (a) ​ 2021 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 26,860 ​ $ 27,372 ​ $ — ​ $ — ​ $ 27,372 Equity securities (c) ​ ​ 3,230 ​ ​ 3,230 ​ ​ — ​ ​ — ​ ​ 3,230 Derivatives - Interest rate contracts (d) ​ 3,279 ​ 3,279 ​ — ​ 3,279 ​ — Total assets ​ $ 33,369 ​ $ 33,881 ​ $ — ​ $ 3,279 ​ $ 30,602 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,033,764 ​ $ 1,032,582 ​ $ — ​ $ — ​ $ 1,032,582 Secured debt instruments - variable rate: (e) ​ ​ ​ ​ ​ ​ Tax-exempt secured notes payable ​ 27,000 ​ 27,000 ​ — ​ — ​ 27,000 Unsecured debt instruments: (e) ​ ​ ​ ​ ​ ​ ​ Working capital credit facility ​ ​ 29,546 ​ ​ 29,546 ​ ​ — ​ ​ — ​ ​ 29,546 Commercial paper program ​ ​ 220,000 ​ ​ 220,000 ​ ​ — ​ ​ — ​ ​ 220,000 Unsecured notes ​ ​ 4,133,083 ​ ​ 4,199,363 ​ ​ — ​ ​ — ​ ​ 4,199,363 Total liabilities ​ $ 5,443,393 ​ $ 5,508,491 ​ $ — ​ $ — ​ $ 5,508,491 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 1,299,442 ​ $ 1,299,442 ​ $ — ​ $ 1,299,442 ​ $ — (a) Certain balances include fair market value adjustments and exclude deferred financing costs. (b) See Note 2, Significant Accounting Policies . (c) The Company holds a direct investment in a publicly traded real estate technology company, SmartRent, that was previously subject to a lock-up restriction on selling or transferring the investment, which expired in February 2022. The investment is valued at the market price on March 31, 2022 and as of December 31, 2021, was valued at the market price on December 31, 2021 less an illiquidity discount of 15.0% . Since the lock-up restriction expired, the Company currently classifies the investment as Level 1 in the fair value hierarchy. The Company previously classified the investment as Level 3 in the fair value hierarchy based upon the lock-up restriction. During the three months ended March 31, 2022, the Company increased its direct investment in SmartRent through a stock distribution from its unconsolidated real estate technology investments. (d) See Note 11, Derivatives and Hedging Activity . (e) See Note 7, Secured and Unsecured Debt, Net . (f) See Note 9, Noncontrolling Interests. Other than described in footnote (c) above, there were no transfers into or out of any of the levels of the fair value hierarchy during the three months ended March 31, 2022. Financial Instruments Carried at Fair Value The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The fair values of interest rate swaps and caps are determined using the market standard methodology of discounting the future expected cash receipts that would occur if variable interest rates rise above the strike rate of the caps. The variable interest rates used in the calculation of projected receipts on the cap are based on an expectation of future interest rates derived from observable market interest rate curves and volatilities. The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees. Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. However, as of March 31, 2022 and December 31, 2021, the Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. In conjunction with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio. Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership have a redemption feature and are marked to their redemption value. The redemption value is based on the fair value of the Company’s common stock at the redemption date, and therefore, is calculated based on the fair value of the Company’s common stock at the balance sheet date. Since the valuation is based on observable inputs such as quoted prices for similar instruments in active markets, redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership are classified as Level 2. Financial Instruments Not Carried at Fair Value At March 31, 2022 and December 31, 2021, the fair values of cash and cash equivalents, restricted cash, accounts receivable, prepaids, real estate taxes payable, accrued interest payable, security deposits and prepaid rent, distributions payable and accounts payable approximated their carrying values because of the short term nature of these instruments. The estimated fair values of other financial instruments, which includes notes receivable and debt instruments, are classified in Level 3 of the fair value hierarchy due to the significant unobservable inputs that are utilized in their respective valuations.

DERIVATIVES AND HEDGING ACTIVIT

DERIVATIVES AND HEDGING ACTIVITY	3 Months Ended
	Mar. 31, 2022
DERIVATIVES AND HEDGING ACTIVITY
DERIVATIVES AND HEDGING ACTIVITY	11. DERIVATIVES AND HEDGING ACTIVITY Risk Management Objective of Using Derivatives The Company is exposed to certain risks arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk, primarily by managing the amount, sources, and duration of its debt funding and through the use of derivative financial instruments. Specifically, the Company may enter into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s investments and borrowings. Cash Flow Hedges of Interest Rate Risk The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company primarily uses interest rate swaps and caps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Interest rate caps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty if interest rates rise above the strike rate on the contract in exchange for an up-front premium. The changes in the fair value of derivatives designated and that qualify as cash flow hedges are recorded in Accumulated other comprehensive income/(loss), net Amounts reported in Accumulated other comprehensive income/(loss), net Interest expense As of March 31, 2022, the Company had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ Number of ​ Product ​ Instruments ​ Notional Interest rate swaps and caps (a) ​ 4 ​ $ 334,880 (a) In addition to the interest rate swaps summarized above, the Company entered into two additional interest rate swaps with a total notional value of $175.0 million that will become effective in July 2022 upon maturity of the $315.0 million of the notional value of the interest rate swaps included above. Derivatives not designated as hedges are not speculative and are used to manage the Company’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings. As of March 31, 2022, no derivatives not designated as hedges were held by the Company. Tabular Disclosure of Fair Values of Derivative Instruments on the Consolidated Balance Sheets The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of March 31, 2022 and December 31, 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asset Derivatives ​ Liability Derivatives ​ ​ (included in Other assets ) ​ (included in Other liabilities ) ​ ​ Fair Value at: ​ Fair Value at: ​ ​ March 31, ​ December 31, ​ March 31, ​ December 31, ​ ​ 2022 ​ 2021 ​ 2022 ​ 2021 Derivatives designated as hedging instruments: ​ ​ ​ ​ Interest rate products ​ $ 10,488 ​ $ 3,279 ​ $ — ​ $ — ​ Tabular Disclosure of the Effect of Derivative Instruments on the Consolidated Statements of Operations The tables below present the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the three months ended March 31, 2022 and 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain/(Loss) Recognized in ​ ​ ​ ​ Gain/(Loss) Reclassified ​ Interest expense ​ ​ Unrealized holding gain/(loss) ​ from Accumulated OCI into ​ (Amount Excluded from ​ ​ Recognized in OCI ​ Interest expense ​ Effectiveness Testing) Derivatives in Cash Flow Hedging Relationships 2022 2021 2022 2021 2022 2021 Three Months Ended March 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate products ​ $ 7,193 ​ $ 127 ​ $ (387) ​ $ (446) ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ ​ 2022 ​ 2021 Total amount of Interest expense ​ $ 35,916 ​ $ 78,156 ​ Credit-risk-related Contingent Features The Company has agreements with its derivative counterparties that contain a provision where the Company could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the Company’s default on the indebtedness. The Company has certain agreements with some of its derivative counterparties that contain a provision where, in the event of default by the Company or the counterparty, the right of setoff may be exercised. Any amount payable to one party by the other party may be reduced by its setoff against any amounts payable by the other party. Events that give rise to default by either party may include, but are not limited to, the failure to pay or deliver payment under the derivative agreement, the failure to comply with or perform under the derivative agreement, bankruptcy, a merger without assumption of the derivative agreement, or in a merger, a surviving entity’s creditworthiness is materially weaker than the original party to the derivative agreement. Tabular Disclosure of Offsetting Derivatives The Company has elected not to offset derivative positions on the consolidated financial statements. The tables below present the effect on its financial position had the Company made the election to offset its derivative positions as of March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Net Amounts of Gross Amounts Not Offset ​ ​ ​ ​ ​ ​ ​ ​ Amounts ​ Assets ​ in the Consolidated ​ ​ ​ ​ ​ Gross ​ Offset in the ​ Presented in the ​ Balance Sheets ​ ​ ​ ​ ​ Amounts of ​ Consolidated ​ Consolidated ​ ​ ​ ​ Cash ​ ​ ​ ​ ​ Recognized ​ Balance ​ Balance Sheets ​ Financial ​ Collateral ​ ​ ​ Offsetting of Derivative Assets ​ Assets ​ Sheets ​ (a) ​ Instruments Received Net Amount March 31, 2022 ​ $ 10,488 ​ $ — ​ $ 10,488 ​ $ — ​ $ — ​ $ 10,488 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ $ 3,279 ​ $ — ​ $ 3,279 ​ $ — ​ $ — ​ $ 3,279 (a) Amounts reconcile to the aggregate fair value of derivative assets in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Consolidated Balance Sheets” located in this footnote. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Net Amounts of Gross Amounts Not Offset ​ ​ ​ ​ ​ ​ ​ ​ Amounts ​ Liabilities ​ in the Consolidated ​ ​ ​ ​ ​ Gross ​ Offset in the ​ Presented in the ​ Balance Sheets ​ ​ ​ ​ ​ Amounts of ​ Consolidated ​ Consolidated ​ ​ ​ ​ Cash ​ ​ ​ ​ ​ Recognized ​ Balance ​ Balance Sheets ​ Financial ​ Collateral ​ ​ ​ Offsetting of Derivative Liabilities Liabilities Sheets (a) Instruments Posted Net Amount March 31, 2022 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — (a) Amounts reconcile to the aggregate fair value of derivative liabilities in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Consolidated Balance Sheets” located in this footnote.

STOCK BASED COMPENSATION

STOCK BASED COMPENSATION	3 Months Ended
	Mar. 31, 2022
EMPLOYEE BENEFIT PLANS.
STOCK BASED COMPENSATION	12. STOCK BASED COMPENSATION The Company recognized stock based compensation expense, inclusive of awards granted to our non-employee directors, net of capitalization, of $6.4 million and $4.9 million during the three months ended March 31, 2022 and 2021, respectively, which are included in General and Administrative

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2022
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES	13. COMMITMENTS AND CONTINGENCIES Commitments Real Estate Commitments The following summarizes the Company’s real estate commitments at March 31, 2022 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number ​ UDR's ​ UDR's Remaining ​ ​ ​ Properties ​ Investment (a) ​ Commitment ​ Wholly-owned — under development 7 ​ $ 458,111 ​ $ 230,889 Joint ventures: ​ ​ Preferred equity investments 3 ​ ​ 76,382 (b) ​ 24,691 (b) Real estate technology investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ RETV I (c) ​ - ​ ​ 51,912 ​ ​ 5,220 ​ RETV II ​ - ​ ​ 7,818 ​ ​ 10,800 ​ RET Strategic Fund ​ - ​ ​ 7,517 ​ ​ 17,500 ​ Climate Technology Funds (d) ​ - ​ ​ 5,721 ​ ​ 4,279 ​ Total ​ $ 607,461 ​ $ 293,379 (a) Represents UDR’s investment as of March 31, 2022. (b) Represents UDR’s investment in and remaining commitment for Makers Rise, Infield Phase I and Upton Place, which are under development as of March 31, 2022. (c) Includes the impact of unrealized losses for the three months ended March 31, 2022, which primarily relate to a decrease in SmartRent's public share price . (See Note 5, Joint Ventures and Partnerships). (d) In March 2022, the Company committed to invest $10.0 million in climate technology funds and funded $5.7 million. As of March 31, 2022, the investment is recorded in Other Assets on the Consolidated Balance Sheets. Purchase Commitments ​ In February 2022, the Company entered into a contract to acquire a to-be-developed parcel of land located in Fort Lauderdale, Florida for a purchase price of $16.0 million. The acquisition is expected to close in the second quarter of 2022. ​ Subsequent to quarter-end, we committed to invest $10.0 million in an ESG Technology Fund. ​ Contingencies Litigation and Legal Matters The Company is subject to various legal proceedings and claims arising in the ordinary course of business. The Company cannot determine the ultimate liability with respect to such legal proceedings and claims at this time. The Company believes that such liability, to the extent not provided for through insurance or otherwise, will not have a material adverse effect on our financial condition, results of operations or cash flows.

REPORTABLE SEGMENTS

REPORTABLE SEGMENTS	3 Months Ended
	Mar. 31, 2022
REPORTABLE SEGMENTS
REPORTABLE SEGMENTS	14. REPORTABLE SEGMENTS GAAP guidance requires that segment disclosures present the measure(s) used by the Chief Operating Decision Maker to decide how to allocate resources and for purposes of assessing such segments’ performance. UDR’s Chief Operating Decision Maker is comprised of several members of its executive management team who use several generally accepted industry financial measures to assess the performance of the business for our reportable operating segments. UDR owns and operates multifamily apartment communities that generate rental and other property related income through the leasing of apartment homes to a diverse base of tenants. The primary financial measures for UDR’s apartment communities are rental income and net operating income (“NOI”). Rental income represents gross market rent less adjustments for concessions, vacancy loss and bad debt. NOI is defined as rental income less direct property rental expenses. Rental expenses include real estate taxes, insurance, personnel, utilities, repairs and maintenance, administrative and marketing. Excluded from NOI is property management expense, which is calculated as 3.25% of property revenue, and land rent. Property management expense covers costs directly related to consolidated property operations, inclusive of corporate management, regional supervision, accounting and other costs. UDR’s Chief Operating Decision Maker utilizes NOI as the key measure of segment profit or loss. UDR’s two reportable segments are Same-Store Communities Non-Mature Communities/Other ● Same-Store Communities represent those communities acquired, developed, and stabilized prior to January 1, 2021 and held as of March 31, 2022. A comparison of operating results from the prior year is meaningful as these communities were owned and had stabilized occupancy and operating expenses as of the beginning of the prior period, there is no plan to conduct substantial redevelopment activities, and the community is not classified as held for disposition within the current year. A community is considered to have stabilized occupancy once it achieves 90% occupancy for at least three consecutive months. ● Non-Mature Communities/Other represent those communities that do not meet the criteria to be included in Same-Store Communities , including, but not limited to, recently acquired, developed and redeveloped communities, and the non-apartment components of mixed use properties. Management evaluates the performance of each of our apartment communities on a Same-Store Community Non-Mature Community/Other All revenues are from external customers and no single tenant or related group of tenants contributed 10% or more of UDR’s total revenues during the three months ended March 31, 2022 and 2021. ​ The following is a description of the principal streams from which the Company generates its revenue: Lease Revenue ​ Lease revenue related to leases is recognized on an accrual basis when due from residents or tenants in accordance with ASC 842, Leases ​ Lease revenue also includes all pass-through revenue from retail and residential leases and common area maintenance reimbursements from retail leases. These services represent non-lease components in a contract as the Company transfers a service to the lessee other than the right to use the underlying asset. The Company has elected the practical expedient under the leasing standard to not separate lease and non-lease components from its resident and retail lease contracts as the timing and pattern of revenue recognition for the non-lease component and related lease component are the same and the combined single lease component would be classified as an operating lease. ​ Other Revenue ​ Other revenue is generated by services provided by the Company to its retail and residential tenants and other unrelated third parties. Revenue is measured based on consideration specified in contracts with customers. The Company recognizes when it satisfies a performance obligation by providing the services specified in a contract to the customer. ​ Joint venture management and other fees ​ The Joint venture management and other fees Joint venture management and other fees The following table details rental income and NOI for UDR’s reportable segments for the three months ended March 31, 2022 and 2021, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, (a) ​ 2022 2021 Reportable apartment home segment lease revenue ​ ​ ​ ​ ​ ​ Same-Store Communities (a) ​ ​ ​ West Region ​ $ 111,649 ​ $ 99,766 Mid-Atlantic Region ​ 65,820 ​ 61,847 Northeast Region ​ 64,412 ​ 58,287 Southeast Region ​ 44,322 ​ 38,767 Southwest Region ​ 26,047 ​ 23,211 Non-Mature Communities/Other ​ 33,457 ​ 9,569 Total segment and consolidated lease revenue ​ $ 345,707 ​ $ 291,447 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment other revenue ​ ​ ​ ​ ​ ​ Same-Store Communities (a) ​ ​ ​ West Region ​ $ 2,960 ​ $ 2,710 Mid-Atlantic Region ​ 2,363 ​ 1,909 Northeast Region ​ 1,257 ​ 1,103 Southeast Region ​ 1,792 ​ 1,635 Southwest Region ​ 892 ​ 875 Non-Mature Communities/Other ​ 1,210 ​ 147 Total segment and consolidated other revenue ​ $ 10,474 ​ $ 8,379 ​ ​ ​ ​ ​ ​ ​ Total reportable apartment home segment rental income ​ ​ ​ ​ ​ ​ Same-Store Communities (a) ​ ​ ​ West Region ​ $ 114,609 ​ $ 102,476 Mid-Atlantic Region ​ 68,183 ​ 63,756 Northeast Region ​ 65,669 ​ 59,390 Southeast Region ​ 46,114 ​ 40,402 Southwest Region ​ 26,939 ​ 24,086 Non-Mature Communities/Other ​ 34,667 ​ 9,716 Total segment and consolidated rental income ​ $ 356,181 ​ $ 299,826 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment NOI ​ ​ Same-Store Communities (a) ​ ​ West Region ​ $ 85,636 ​ $ 74,593 Mid-Atlantic Region ​ 46,983 ​ 43,620 Northeast Region ​ 42,083 ​ 36,328 Southeast Region ​ 31,461 ​ 26,645 Southwest Region ​ 17,339 ​ 14,835 Non-Mature Communities/Other ​ 20,431 ​ 5,037 Total segment and consolidated NOI ​ 243,933 ​ 201,058 Reconciling items: ​ ​ Joint venture management and other fees ​ 1,085 ​ 1,615 Property management ​ (11,576) ​ (8,995) Other operating expenses ​ (4,712) ​ (4,435) Real estate depreciation and amortization ​ (163,622) ​ (144,088) General and administrative ​ (14,908) ​ (12,736) Casualty-related (charges)/recoveries, net ​ 765 ​ (5,577) Other depreciation and amortization ​ (3,075) ​ (2,601) Gain/(loss) on sale of real estate owned ​ ​ — ​ ​ 50,829 Income/(loss) from unconsolidated entities ​ 5,412 ​ 4,922 Interest expense ​ (35,916) ​ (78,156) Interest income and other income/(expense), net ​ (2,440) ​ 2,057 Tax (provision)/benefit, net ​ (343) ​ (619) Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (879) ​ (154) Net (income)/loss attributable to noncontrolling interests ​ (19) ​ (16) Net income/(loss) attributable to UDR, Inc. ​ $ 13,705 ​ $ 3,104 (a) Same-Store Community population consisted of 47,443 apartment homes. ​ The following table details the assets of UDR’s reportable segments as of March 31, 2022 and December 31, 2021 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Reportable apartment home segment assets: ​ ​ Same-Store Communities (a): ​ ​ West Region ​ $ 4,301,470 ​ $ 4,288,116 Mid-Atlantic Region ​ 2,863,633 ​ 2,856,144 Northeast Region ​ 3,342,355 ​ 3,338,497 Southeast Region ​ 1,212,612 ​ 1,208,183 Southwest Region ​ 902,350 ​ 900,931 Non-Mature Communities/Other ​ 2,210,635 ​ 2,148,932 Total segment assets ​ 14,833,055 ​ 14,740,803 Accumulated depreciation ​ (5,289,853) ​ (5,137,096) Total segment assets — net book value ​ 9,543,202 ​ 9,603,707 Reconciling items: ​ ​ Cash and cash equivalents ​ 895 ​ 967 Restricted cash ​ 26,032 ​ 27,451 Notes receivable, net ​ 26,577 ​ 26,860 Investment in and advances to unconsolidated joint ventures, net ​ 669,343 ​ 702,461 Operating lease right-of-use assets ​ ​ 196,578 ​ ​ 197,463 Other assets ​ 222,337 ​ 216,311 Total consolidated assets ​ $ 10,684,964 ​ $ 10,775,220 (a) Same-Store Community population consisted of 47,443 apartment homes. ​ Markets included in the above geographic segments are as follows: i. West Region — Orange County, San Francisco, Seattle, Monterey Peninsula, Los Angeles, Other Southern California and Portland ii. Mid-Atlantic Region — Metropolitan D.C., Baltimore and Richmond iii. Northeast Region — Boston, New York and Philadelphia iv. Southeast Region — Tampa, Orlando, Nashville and Other Florida v. Southwest Region — Dallas, Austin and Denver

SIGNIFICANT ACCOUNTING POLICI_2

SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2022
SIGNIFICANT ACCOUNTING POLICIES
Recent Accounting Pronouncements	Recent Accounting Pronouncements In March 2020, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2020-04, Reference Rate Reform (Topic 848)
Principles of Consolidation	Principles of Consolidation The Company accounts for subsidiary partnerships, joint ventures and other similar entities in which it holds an ownership interest in accordance with the consolidation guidance. The Company first evaluates whether each entity is a variable interest entity (“VIE”). Under the VIE model, the Company consolidates an entity when it has control to direct the activities of the VIE and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. Under the voting model, the Company consolidates an entity when it controls the entity through ownership of a majority voting interest.
Real Estate Sales Gain Recognition	Real Estate Sales Gain Recognition ​ For sale transactions resulting in a transfer of a controlling financial interest of a property, the Company generally derecognizes the related assets and liabilities from its Consolidated Balance Sheets and records the gain or loss in the period in which the transfer of control occurs. If control of the property has not transferred to the counterparty, the criteria for derecognition are not met and the Company will continue to recognize the related assets and liabilities on its Consolidated Balance Sheets. ​ Sale transactions to entities in which the Company sells a controlling financial interest in a property but retains a noncontrolling interest are accounted for as partial sales. Partial sales resulting in a change in control are accounted for at fair value and a full gain or loss is recognized. Therefore, the Company will record a gain or loss on the partial interest sold, and the initial measurement of our retained interest will be accounted for at fair value. ​ Sales of real estate to joint ventures or other noncontrolled investees are also accounted for at fair value and the Company will record a full gain or loss in the period the property is contributed. ​ To the extent that the Company acquires a controlling financial interest in a property that it previously accounted for as an equity method investment, the Company will not remeasure its previously held interest if the acquisition is treated as an asset acquisition. The Company will include the carrying amount of its previously held equity method interest along with the consideration paid and transaction costs incurred in determining the amounts to allocate to the related assets and liabilities acquired on its Consolidated Balance Sheets. When treated as an asset acquisition, the Company will not recognize a gain or loss on consolidation of a property.
Allowance for Credit Losses	Allowance for Credit Losses The Company accounts for allowance for credit losses under the current expected credit loss (“CECL”) impairment model for its financial assets, including trade and other receivables, held-to-maturity debt securities, loans and other financial instruments, and presents the net amount of the financial instrument expected to be collected. The CECL impairment model excludes operating lease receivables. The CECL impairment model requires an estimate of expected credit losses, measured over the contractual life of an instrument, that considers forecasts of future economic conditions in addition to information about past events and current conditions. Based on this model, we analyze the following criteria, as applicable in developing allowances for credit losses: historical loss information, the borrower’s ability to make scheduled payments, the remaining time to maturity, the value of underlying collateral, projected future performance of the borrower and macroeconomic trends. ​ The Company measures credit losses of financial assets on a collective (pool) basis when similar risk characteristics exist. If the Company determines that a financial asset does not share risk characteristics with the Company’s other financial assets, the Company evaluates the financial asset for expected credit losses on an individual basis. Allowance for credit losses are recorded as a direct reduction from an asset’s amortized cost basis. Credit losses and recoveries are recorded in Interest income and other income/(expense), net ​ The Company has made the optional election provided by the standard not to measure allowance for credit losses for accrued interest receivables as the Company writes off any uncollectible accrued interest receivables in a timely manner. The Company periodically evaluates the collectability of its accrued interest receivables. A write-off is recorded when the Company concludes that all or a portion of its accrued interest receivable balance is no longer collectible.
Notes Receivable	Notes Receivable Notes receivable relate to financing arrangements which are typically secured by assets of the borrower that may include real estate assets. Certain of the loans we extend may include characteristics such as options to purchase the project within a specific time window following expected project completion. These characteristics can cause the loans to fall under the definition of a VIE, and thus trigger consolidation consideration. We consider the facts and circumstances pertinent to each loan, including the relative amount of financing we are contributing to the overall project cost, decision making rights or control we hold, and our rights to expected residual gains or our obligations to absorb expected residual losses from the project. If we are deemed to be the primary beneficiary of a VIE due to holding a controlling financial interest, the majority of decision making control, or by other means, consolidation of the VIE would be required. The Company has concluded that it is not the primary beneficiary of the borrowing entities of the existing loans. Additionally, we analyze each loan arrangement that involves real estate development to consider whether the loan qualifies for accounting as a loan or as an investment in a real estate development project. The Company has evaluated its real estate loans, where appropriate, for accounting treatment as loans versus real estate development projects, as required by ASC 310-10. For each loan, the Company has concluded that the characteristics and the facts and circumstances indicate that loan accounting treatment is appropriate. The following table summarizes our Notes receivable, net dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate at ​ Balance Outstanding ​ March 31, March 31, December 31, ​ ​ 2022 ​ 2022 ​ 2021 Note due May 2022 (a) ​ N/A ​ $ — ​ $ 2,760 Note due January 2023 (b) ​ 10.00 % ​ 26,710 ​ ​ 24,235 Notes Receivable ​ ​ ​ ​ 26,710 ​ ​ 26,995 Allowance for credit losses ​ ​ ​ ​ (133) ​ ​ (135) Total notes receivable, net ​ $ 26,577 ​ $ 26,860 (a) The Company previously had a secured note with an unaffiliated third party with an aggregate commitment of $2.8 million. The note was secured by a parcel of land located in Kissimmee, Florida. In March 2022, the unaffiliated third party repaid the $2.8 million secured note in full. (b) The Company has a secured note with an unaffiliated third party with an aggregate commitment of $30.4 million. In March 2022, the terms of this secured note were amended to increase the aggregate commitment from $25.4 million to $30.4 million. Following the March 2022 note amendment, the balance increased to $26.7 million . Interest payments are due monthly. The note is secured by substantially all of the borrower’s assets and matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) January 2023. The Company recognized $0.7 million and $1.9 million of interest income for the notes receivable described above during the three months ended March 31, 2022 and 2021, respectively, none of which was related party interest. Interest income is included in Interest income and other income/(expense), net
Comprehensive Income/(Loss)	Comprehensive Income/(Loss) Comprehensive income/(loss), which is defined as the change in equity during each period from transactions and other events and circumstances from nonowner sources, including all changes in equity during a period except for those resulting from investments by or distributions to stockholders, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the three months ended March 31, 2022 and 2021, the Company’s other comprehensive income/(loss) consisted of the gain/(loss) on derivative instruments that are designated as and qualify as cash flow hedges, (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) into earnings, and the allocation of other comprehensive income/(loss) to noncontrolling interests. The (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) is included in Interest expense Derivatives and Hedging Activity,
Income Taxes	Income Taxes Due to the structure of the Company as a REIT and the nature of the operations for the operating properties, no provision for federal income taxes has been provided for at UDR. Historically, the Company has generally incurred only state and local excise and franchise taxes. UDR has elected for certain consolidated subsidiaries to be treated as taxable REIT subsidiaries (“TRS”). Income taxes for our TRS are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rate is recognized in earnings in the period of the enactment date. The Company’s deferred tax assets/(liabilities) are generally the result of differing depreciable lives on capitalized assets, temporary differences between book and tax basis of assets and liabilities and timing of expense recognition for certain accrued liabilities. As of March 31, 2022 and December 31, 2021, UDR’s net deferred tax asset/(liability) was ($0.8) million and ($0.8) million, respectively, and are recorded in Accounts payable, accrued expenses and other liabilities GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition. The Company recognizes and evaluates its tax positions using a two-step process. First, UDR determines whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. Second, the Company will determine the amount of benefit to recognize and record the amount that is more likely than not to be realized upon ultimate settlement. The Company invests in assets that qualify for federal investment tax credits (“ITC”) through our TRS. An ITC reduces federal income taxes payable when qualifying depreciable property is acquired. The ITC is determined as a percentage of cost of the assets. The Company accounts for ITCs under the deferral method, under which the tax benefit from the ITC is deferred and amortized as a tax benefit into Tax (provision)/benefit, net Accounts payable, accrued expenses and other liabilities UDR had no material unrecognized tax benefit, accrued interest or penalties at March 31, 2022. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2018 through 2020 remain open to examination by tax jurisdictions to which we are subject. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in Tax (provision)/benefit, net
Forward Sales Agreements	Forward Sales Agreements ​ From time to time the Company utilizes forward sales agreements for the future issuance of its common stock. When the Company enters into a forward sales agreement, the contract requires the Company to sell its shares to a counterparty at a predetermined price at a future date. The net sales price and proceeds attained by the Company will be determined on the dates of settlement, with adjustments during the term of the contract for the Company’s anticipated dividends as well as for a daily interest factor that varies with changes in the federal funds rate. The Company generally has the ability to determine the dates and method of settlement (i.e., gross physical settlement, net share settlement or cash settlement), subject to certain conditions and the right of the counterparty to accelerate settlement under certain circumstances. ​ The Company accounts for the shares of common stock reserved for issuance upon settlement as equity in accordance with ASC 815-40, Contracts in Entity's Own Equity ​ The guidance establishes a two-step process for evaluating whether an equity-linked financial instrument is considered indexed to the entity’s own stock, first, evaluating the instrument’s contingent exercise provisions and second, evaluating the instrument’s settlement provisions. When entering into forward sales agreements, we determined that (i) none of the agreement’s exercise contingencies are based on observable markets or indices besides those related to the market for our own stock price; and (ii) none of the settlement provisions preclude the agreements from being indexed to our own stock. ​ Before the issuance of shares of common stock, upon physical or net share settlement of the forward sales agreements, the Company expects that the shares issuable upon settlement of the forward sales agreements will be reflected in its diluted income/(loss) per share calculations using the treasury stock method. Under this method, the number of shares of common stock used in calculating diluted income/(loss) per share is deemed to be increased by the excess, if any, of the number of shares of common stock that would be issued upon full physical settlement of the forward sales agreements over the number of shares of common stock that could be purchased by the Company in the open market (based on the average market price during the period) using the proceeds receivable upon full physical settlement (based on the adjusted forward sale price at the end of the reporting period). When the Company physically or net share settles any forward sales agreement, the delivery of shares of common stock would result in an increase in the number of weighted average common shares outstanding and dilution to basic income/(loss) per share. (See Note 8, Income/(Loss) per Share
Impact of COVID-19 Pandemic	Impact of COVID-19 Pandemic ​ We continue to monitor the status and respond to the effects of the COVID-19 pandemic and its impact on our business. While the pandemic and related government measures adversely impacted our business in certain prior periods, the extent of the impact generally has decreased. Future developments regarding COVID-19, however, continue to be uncertain and difficult to predict. There can be no assurances that closures or restrictions in response to COVID-19, including due to new variants, will not be imposed in the future or that other developments related to COVID-19 will not adversely affect our business, results of operations, financial condition and cash flows in future periods. ​ During the three months ended March 31, 2022, the Company performed an analysis in accordance with the ASC 842, Leases, guidance to assess the collectibility of its operating lease receivables in light of the COVID-19 pandemic. This analysis included an assessment of collectibility of current and future rents and whether those lease payments were no longer probable of collection. In accordance with the leases guidance, if lease payments are no longer deemed to be probable over the life of the lease contract, we recognize revenue only when cash is received, and all existing contractual operating lease receivables and straight-line lease receivables are reserved. ​ As a result of its analysis, the Company reduced its reserve by approximately $1.3 million for multifamily tenant lease receivables and approximately $1.2 million for retail tenant lease receivables for its wholly-owned communities and communities held by joint ventures for the three months ended March 31, 2022. In aggregate, the reduction in reserve is reflected as a $2.3 million increase to Rental income and a $0.2 million increase to Income/(loss) from unconsolidated entities on the Consolidated Statements of Operations for the three months ended March 31, 2022 . The impact to deferred leasing commissions was not material for the three months ended March 31, 2022. ​ The Company did not recognize any other adjustments to the carrying amounts of assets or asset impairment charges due to the COVID-19 pandemic for the three months ended March 31, 2022 .

SIGNIFICANT ACCOUNTING POLICI_3

SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2022
SIGNIFICANT ACCOUNTING POLICIES
Summary of notes receivable, net	The following table summarizes our Notes receivable, net dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate at ​ Balance Outstanding ​ March 31, March 31, December 31, ​ ​ 2022 ​ 2022 ​ 2021 Note due May 2022 (a) ​ N/A ​ $ — ​ $ 2,760 Note due January 2023 (b) ​ 10.00 % ​ 26,710 ​ ​ 24,235 Notes Receivable ​ ​ ​ ​ 26,710 ​ ​ 26,995 Allowance for credit losses ​ ​ ​ ​ (133) ​ ​ (135) Total notes receivable, net ​ $ 26,577 ​ $ 26,860 (a) The Company previously had a secured note with an unaffiliated third party with an aggregate commitment of $2.8 million. The note was secured by a parcel of land located in Kissimmee, Florida. In March 2022, the unaffiliated third party repaid the $2.8 million secured note in full. (b) The Company has a secured note with an unaffiliated third party with an aggregate commitment of $30.4 million. In March 2022, the terms of this secured note were amended to increase the aggregate commitment from $25.4 million to $30.4 million. Following the March 2022 note amendment, the balance increased to $26.7 million . Interest payments are due monthly. The note is secured by substantially all of the borrower’s assets and matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) January 2023.

REAL ESTATE OWNED (Tables)

REAL ESTATE OWNED (Tables)	3 Months Ended
	Mar. 31, 2022
REAL ESTATE OWNED
Summary of carrying amounts for real estate owned (at cost)	​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Land ​ $ 2,325,852 ​ $ 2,342,385 Depreciable property — held and used: ​ ​ ​ Land improvements ​ 242,835 ​ 241,905 Building, improvements, and furniture, fixtures and equipment ​ 11,756,244 ​ 11,717,931 Real estate intangible assets ​ ​ 50,013 ​ ​ 50,013 Under development: ​ ​ Land and land improvements ​ 90,932 ​ 74,399 Building, improvements, and furniture, fixtures and equipment ​ 367,179 ​ 314,170 Real estate owned ​ 14,833,055 ​ 14,740,803 Accumulated depreciation (a) ​ (5,289,853) ​ (5,137,096) Real estate owned, net ​ $ 9,543,202 ​ $ 9,603,707 (a) Accumulated depreciation is inclusive of $10.2 million and $8.8 million of accumulated amortization related to real estate intangible assets as of March 31, 2022 and December 31, 2021, respectively.

JOINT VENTURES AND PARTNERSHI_2

JOINT VENTURES AND PARTNERSHIPS (Tables)	3 Months Ended
	Mar. 31, 2022
JOINT VENTURES AND PARTNERSHIPS
Schedule of unconsolidated joint ventures and partnerships	The following table summarizes the Company’s investment in and advances to unconsolidated joint ventures and partnerships, net, which are accounted for under the equity method of accounting as of March 31, 2022 and December 31, 2021 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Number of ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ Apartment ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ ​ ​ Communities ​ Homes ​ Investment at ​ UDR’s Ownership Interest ​ ​ Three Months Ended ​ Location of March 31, March 31, March 31, December 31, ​ March 31, ​ December 31, ​ March 31, Joint Ventures Properties 2022 2022 2022 2021 ​ 2022 ​ 2021 ​ 2022 2021 Operating: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ UDR/MetLife I ​ Los Angeles, CA ​ 1 ​ 150 ​ $ 22,936 ​ $ 23,880 ​ 50.0 % ​ 50.0 % ​ $ (625) ​ $ (475) UDR/MetLife II Various 7 1,250 ​ 179,223 ​ 181,023 ​ 50.0 % ​ 50.0 % ​ ​ 100 ​ ​ (2,684) Other UDR/MetLife Joint Ventures (a) Various 5 1,437 ​ 62,233 ​ 66,012 ​ 50.6 % ​ 50.6 % ​ ​ (2,113) ​ ​ (3,382) Investment in and advances to unconsolidated joint ventures, net, before preferred equity investments and real estate technology investments ​ $ 264,392 ​ $ 270,915 ​ ​ ​ ​ $ (2,638) ​ $ (6,541) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment at ​ Three Months Ended Developer Capital Program ​ ​ Years To ​ UDR March 31, December 31, ​ March 31, and Real Estate Technology Investments (b) Location Rate Maturity ​ Commitment (c) 2022 2021 2022 2021 Preferred equity investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ 1532 Harrison ​ San Francisco, CA ​ 11.0 % 0.2 ​ $ 24,645 ​ $ 34,945 ​ $ 35,248 ​ $ (6) ​ $ 929 Junction ​ Santa Monica, CA ​ 12.0 % 0.3 ​ ​ 8,800 ​ ​ 13,577 ​ ​ 13,183 ​ ​ 394 ​ ​ 350 1200 Broadway (d) (e) ​ Nashville, TN ​ N/A ​ — ​ ​ — ​ ​ — ​ ​ 61,326 ​ ​ 11,893 ​ ​ 1,372 1300 Fairmount (e) ​ Philadelphia, PA ​ 8.5 % 1.4 ​ ​ 51,393 ​ ​ 66,146 ​ ​ 64,780 ​ ​ 1,366 ​ ​ 1,255 Modera Lake Merritt (e) ​ Oakland, CA ​ 9.0 % 2.0 ​ ​ 27,250 ​ ​ 34,584 ​ ​ 33,828 ​ ​ 756 ​ ​ 691 Thousand Oaks (e) ​ Thousand Oaks, CA ​ 9.0 % 2.9 ​ ​ 20,059 ​ ​ 23,272 ​ ​ 22,764 ​ ​ 508 ​ ​ 438 Vernon Boulevard (e) ​ Queens, NY ​ 13.0 % 3.3 ​ ​ 40,000 ​ ​ 49,771 ​ ​ 48,210 ​ ​ 1,561 ​ ​ 1,372 Makers Rise (e) ​ Herndon, VA ​ 9.0 % 3.8 ​ ​ 30,208 ​ ​ 31,583 ​ ​ 22,828 ​ ​ 644 ​ ​ 96 121 at Watters (e) ​ Allen, TX ​ 9.0 % 3.9 ​ ​ 19,843 ​ ​ 21,045 ​ ​ 14,134 ​ ​ 394 ​ ​ 2 Infield Phase I ​ Kissimmee, FL ​ 14.0 % 2.1 ​ ​ 16,044 ​ ​ 7,567 ​ ​ — ​ ​ 86 ​ ​ — Upton Place ​ Washington, D.C. ​ 9.7 % 5.7 ​ ​ 52,163 ​ ​ 37,232 ​ ​ 29,566 ​ ​ 676 ​ ​ — Meetinghouse (f) ​ Portland, OR ​ 8.25 % 4.9 ​ ​ 11,600 ​ ​ 11,603 ​ ​ — ​ ​ 3 ​ ​ — Real estate technology investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ RETV I (g) ​ N/A ​ N/A ​ N/A ​ ​ 18,000 ​ ​ 51,912 ​ ​ 71,464 ​ ​ (10,111) ​ ​ 2,051 RETV II ​ N/A ​ N/A ​ N/A ​ ​ 18,000 ​ ​ 7,818 ​ ​ 8,130 ​ ​ (114) ​ ​ (101) RET Strategic Fund (h) ​ N/A ​ N/A ​ N/A ​ ​ 25,000 ​ ​ 7,517 ​ ​ — ​ ​ — ​ ​ — Total Preferred Equity Investments and Real Estate Technology Investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 398,572 ​ ​ 425,461 ​ ​ 8,050 ​ ​ 8,455 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sold joint ventures and other investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ — ​ ​ — ​ ​ — ​ ​ 3,008 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Joint Ventures and Developer Capital Program and Real Estate Technology Investments, net (a) ​ ​ ​ ​ $ 662,964 ​ $ 696,376 ​ $ 5,412 $ 4,922 (a) As of March 31, 2022 and December 31, 2021, the Company’s negative investment in 13 th and Market Properties LLC of $6.4 million and $6.1 million, respectively, is included in Other UDR/MetLife Joint Ventures in the table above and recorded in Accounts payable, accrued expenses, and other liabilities on the Consolidated Balance Sheet. (b) The Developer Capital Program is the program through which the Company makes investments, including preferred equity investments, mezzanine loans or other structured investments that may receive a fixed yield on the investment and may include provisions pursuant to which the Company participates in the increase in value of the property upon monetization of the applicable property. (c) Represents UDR’s maximum funding commitment only and therefore excludes other activity such as income from investments. (d) In J anuary 2022, the joint venture sold its community, a 313 apartment home operating community located in Nashville, Tennessee, for a sales price of approximately $294.0 million. As a result, the Company recorded variable upside participation on the sale of approximately $10.6 million, net of associated costs. (e) The Company’s preferred equity investment receives a variable percentage of the value created from the project upon a capital or liquidating event. (f) In March 2022, the Company entered into a joint venture agreement with an unaffiliated joint venture partner to operate a 232 apartment home community in Portland, Oregon. The Company’s preferred equity investment of $11.6 million earns a preferred return of 8.25% per annum. The unaffiliated joint venture partner is the managing member of the joint venture. The Company has concluded that it does not control the joint venture and accounts for it under the equity method of accounting . (g) The Company recognized $(10.1) million and $2.1 million of investment income/(loss) from RETV I for the three months ended March 31, 2022 and 2021, respectively, which primarily related to unrealized gains/(losses) from one portfolio investment held by RETV I, SmartRent, Inc. (“SmartRent”). In 2021, SmartRent, a provider of smart home automation solutions, went public through a merger with a publicly traded special purpose acquisition company. As a result, SmartRent began trading on the New York Stock Exchange under the ticker symbol “SMRT.” Due to the merger, all shares of SmartRent that RETV I held were converted to publicly traded SmartRent shares based on a pre-determined conversion factor. Following the merger and stock conversion, RETV I began recording its investment in SmartRent based on the share price at the end of the applicable reporting period. (h) In January 2022, the Company entered into a real estate technology investment as a limited partner, for a total commitment of $25.0 million. The Company funded $7.5 million to the limited partnership at closing. The Company has concluded that it does not control the limited partnership and accounts for it under the equity method of accounting.
Combined summary of balance sheets relating to unconsolidated joint ventures and partnerships	Combined summary balance sheets relating to the unconsolidated joint ventures’ and partnerships’ (not just our proportionate share) are presented below as of March 31, 2022 and December 31, 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2022 2021 Total real estate, net $ 2,121,264 $ 2,043,158 Real estate assets held for sale ​ — ​ 168,668 Investments, at fair value ​ ​ 383,143 ​ ​ 460,241 Cash and cash equivalents ​ 31,328 ​ 22,891 Other assets ​ ​ 24,494 ​ 28,948 Total assets $ 2,560,229 $ 2,723,906 ​ ​ ​ ​ ​ ​ ​ Third party debt, net ​ $ 1,245,610 ​ $ 1,215,918 Liabilities held for sale ​ — ​ 106,990 Accounts payable and accrued liabilities ​ ​ 75,487 ​ ​ 51,689 Total liabilities ​ 1,321,097 ​ 1,374,597 Total equity $ 1,239,132 $ 1,349,309
Schedule of combined financial information relating to unconsolidated joint ventures and partnerships operations (not just proportionate share)	Combined summary financial information relating to the unconsolidated joint ventures’ and partnerships’ operations (not just our proportionate share) is presented below for the three months ended March 31, 2022 and 2021 ( dollars in thousands : ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ 2022 2021 Total revenues $ 37,169 $ 32,137 Property operating expenses ​ 17,930 ​ 17,110 Real estate depreciation and amortization ​ 17,820 ​ 16,453 Gain/(loss) on sale of property ​ ​ 127,542 ​ ​ 34,757 Operating income/(loss) ​ 128,961 ​ ​ 33,331 Interest expense ​ (8,132) ​ (12,134) Net realized gain/(loss) on held investments ​ ​ 6,304 ​ ​ 2,494 Net unrealized gain/(loss) on held investments ​ ​ (21,492) ​ ​ 5,994 Other income/(loss) ​ ​ (224) ​ ​ (1,657) Net income/(loss) $ 105,417 $ 28,028

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2022
LEASES
Lessee - Future minimum lease payments and total operating lease liabilities	Future minimum lease payments and total operating lease liabilities from our ground leases as of March 31, 2022 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Ground Leases 2022 ​ $ 9,331 2023 ​ ​ 12,442 2024 ​ ​ 12,442 2025 ​ ​ 12,442 2026 ​ ​ 12,442 Thereafter ​ ​ 430,337 Total future minimum lease payments (undiscounted) ​ ​ 489,436 Difference between future undiscounted cash flows and discounted cash flows ​ ​ (297,747) Total operating lease liabilities (discounted) ​ $ 191,689
Lessee - components of operating lease expenses	The components of operating lease expenses were as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2022 ​ 2021 Lease expense: ​ ​ ​ ​ ​ ​ Contractual lease expense ​ $ 3,311 ​ $ 3,230 Variable lease expense (a) ​ ​ 26 ​ ​ 29 Total operating lease expense (b)(c) ​ $ 3,337 ​ $ 3,259 (a) Variable lease expense includes adjustments such as changes in the consumer price index and payments based on a percentage of a community’s income. (b) Lease expense is reported within the line item Other operating expenses on the Consolidated Statements of Operations. (c) For the three months ended March 31, 2022, Operating lease right-of-use assets and Operating lease liabilities amortized by $0.9 million and $0.8 million, respectively. For the three months ended March 31, 2021, Operating lease right-of-use assets and Operating lease liabilities amortized by $0.8 million and $0.8 million, respectively. Due to the net impact of the amortization, the Company recorded $0.1 million and less than $0.1 million of total operating lease expense during the three months ended March 31, 2022 and 2021, respectively.
Lessor - Future minimum lease payments	Future minimum lease payments from our retail and commercial leases as of March 31, 2022 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Retail and Commercial Leases 2022 ​ $ 18,504 2023 ​ ​ 24,186 2024 ​ ​ 22,012 2025 ​ ​ 18,834 2026 ​ ​ 16,028 Thereafter ​ ​ 68,924 Total future minimum lease payments (a) ​ $ 168,488 (a)

SECURED AND UNSECURED DEBT, N_2

SECURED AND UNSECURED DEBT, NET (Tables)	3 Months Ended
	Mar. 31, 2022
Unsecured Debt
Schedule of debt instruments	The following is a summary of our secured and unsecured debt at March 31, 2022 and December 31, 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal Outstanding ​ As of March 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Average ​ Number of ​ ​ March 31, ​ December 31, ​ Interest ​ Years to ​ Communities ​ 2022 2021 Rate Maturity Encumbered Secured Debt: ​ ​ ​ ​ ​ ​ ​ Fixed Rate Debt ​ ​ Mortgage notes payable (a) ​ $ 1,006,482 ​ $ 1,006,762 3.42 % 6.2 14 Deferred financing costs and other non-cash adjustments (b) ​ 22,686 ​ 23,678 Total fixed rate secured debt, net ​ 1,029,168 ​ 1,030,440 3.42 % 6.2 14 Variable Rate Debt ​ ​ Tax-exempt secured notes payable (c) ​ 27,000 ​ 27,000 0.87 % 10.0 1 Deferred financing costs ​ (58) ​ (60) Total variable rate secured debt, net ​ 26,942 ​ 26,940 0.87 % 10.0 1 Total Secured Debt, net ​ 1,056,110 ​ 1,057,380 3.35 % 6.3 15 Unsecured Debt: ​ ​ Variable Rate Debt ​ ​ Borrowings outstanding under unsecured credit facility due January 2026 (d) (m) ​ — ​ — — % 3.8 Borrowings outstanding under unsecured commercial paper program due April 2022 (e) (m) ​ ​ 280,000 ​ ​ 220,000 ​ 0.77 % 0.1 ​ ​ Borrowings outstanding under unsecured working capital credit facility due January 2024 ​ 37,194 ​ 29,546 1.23 % 1.8 Term Loan due January 2027 (d) (m) ​ 35,000 ​ 35,000 1.08 % 4.8 Fixed Rate Debt ​ ​ Term Loan due January 2027 (d) (m) ​ ​ 315,000 ​ 315,000 1.02 % 4.8 ​ ​ 8.50% Debentures due September 2024 ​ 15,644 ​ 15,644 8.50 % 2.5 2.95% Medium-Term Notes due September 2026 (g) (m) ​ 300,000 ​ 300,000 2.89 % 4.4 3.50% Medium-Term Notes due July 2027 (net of discounts of $370 and $388, respectively) (h) (m) ​ ​ 299,630 ​ ​ 299,612 ​ 4.03 % 5.3 ​ ​ 3.50% Medium-Term Notes due January 2028 (net of discounts of $689 and $717, respectively) (m) ​ ​ 299,311 ​ ​ 299,283 ​ 3.50 % 5.8 ​ ​ 4.40% Medium-Term Notes due January 2029 (net of discounts of $4 and $4, respectively) (i) (m) ​ ​ 299,996 ​ ​ 299,996 ​ 4.27 % 6.8 ​ ​ 3.20% Medium-Term Notes due January 2030 (net of premiums of $10,697 and $11,040, respectively) (j) (m) ​ ​ 610,697 ​ ​ 611,040 ​ 3.32 % 7.8 ​ ​ 3.00% Medium-Term Notes due August 2031 (net of premiums/discounts of $11,200 and $11,498, respectively) (k) (m) ​ ​ 611,200 ​ ​ 611,498 ​ 3.01 % 9.4 ​ ​ 2.10% Medium-Term Notes due August 2032 (net of discounts of $364 and $373, respectively) (m) ​ ​ 399,636 ​ ​ 399,627 ​ 2.10 % 10.3 ​ ​ 1.90% Medium-Term Notes due March 2033 (net of discounts of $1,321 and $1,351, respectively) (m) ​ ​ 348,679 ​ ​ 348,649 ​ 1.90 % 10.9 ​ ​ 2.10% Medium-Term Notes due June 2033 (net of discounts of $1,115 and $1,140, respectively) (m) ​ ​ 298,885 ​ ​ 298,860 ​ 2.10 % 11.2 ​ ​ 3.10% Medium-Term Notes due November 2034 (net of discounts of $1,111 and $1,133, respectively) (l) (m) ​ ​ 298,889 ​ ​ 298,867 ​ 3.13 % 12.6 ​ ​ Other ​ 7 ​ 7 Deferred financing costs ​ (26,868) ​ (27,222) Total Unsecured Debt, net ​ 4,422,900 ​ 4,355,407 2.71 % 7.7 Total Debt, net ​ $ 5,479,010 ​ $ 5,412,787 2.80 % 7.4
Schedule of aggregate maturities, including amortizing principal payments of secured and unsecured debt	The aggregate maturities, including amortizing principal payments on secured and unsecured debt, of total debt for the next ten calendar years subsequent to March 31, 2022 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Fixed Total Variable Total Total Total Year ​ Secured Debt ​ Secured Debt ​ Secured Debt ​ Unsecured Debt ​ Debt 2022 ​ $ 860 ​ $ — ​ $ 860 ​ $ 280,000 (a) $ 280,860 2023 ​ ​ 1,242 ​ ​ — ​ ​ 1,242 ​ ​ — ​ ​ 1,242 2024 ​ 96,747 ​ — ​ 96,747 ​ 52,838 ​ 149,585 2025 ​ 174,793 ​ — ​ 174,793 ​ — ​ 174,793 2026 ​ 52,744 ​ — ​ 52,744 ​ 300,000 ​ 352,744 2027 ​ 2,860 ​ — ​ 2,860 ​ 650,000 ​ 652,860 2028 ​ 162,310 ​ — ​ 162,310 ​ 300,000 ​ 462,310 2029 ​ 191,986 ​ — ​ 191,986 ​ 300,000 ​ 491,986 2030 ​ 162,010 ​ — ​ 162,010 ​ 600,000 ​ 762,010 2031 ​ 160,930 ​ — ​ 160,930 ​ 600,000 ​ 760,930 Thereafter ​ — ​ 27,000 ​ 27,000 ​ 1,350,000 ​ 1,377,000 Subtotal ​ 1,006,482 ​ 27,000 ​ 1,033,482 ​ 4,432,838 ​ 5,466,320 Non-cash (b) ​ 22,686 ​ (58) ​ 22,628 ​ (9,938) ​ 12,690 Total ​ $ 1,029,168 ​ $ 26,942 ​ $ 1,056,110 ​ $ 4,422,900 ​ $ 5,479,010 (a) All unsecured debt due in the remainder of 2022 is related to the Company’s commercial paper program. (b) Includes the unamortized balance of fair market value adjustments, premiums/discounts and deferred financing costs . The Company amortized $0.9 million and $1.2 million, respectively, during the three months ended March 31, 2022 and 2021, of deferred financing costs into Interest expense.
Commercial Paper
Unsecured Debt
Schedule of short-term debt	The following is a summary of short-term bank borrowings under the unsecured commercial paper program at March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Total unsecured commercial paper program $ 700,000 ​ $ 700,000 ​ Borrowings outstanding at end of period ​ 280,000 ​ 220,000 ​ Weighted average daily borrowings during the period ended ​ 280,722 ​ 419,563 ​ Maximum daily borrowings during the period ended ​ 410,000 ​ 700,000 ​ Weighted average interest rate during the period ended ​ 0.4 % 0.2 % Interest rate at end of the period ​ 0.8 % 0.3 %
Revolving Credit Facility
Unsecured Debt
Schedule of short-term debt	The following is a summary of short-term bank borrowings under the Revolving Credit Facility at March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 2021 ​ Total revolving credit facility ​ $ 1,300,000 ​ $ 1,300,000 ​ Borrowings outstanding at end of period (1) ​ — ​ — ​ Weighted average daily borrowings during the period ended ​ — ​ 13,068 ​ Maximum daily borrowings during the period ended ​ — ​ 305,000 ​ Weighted average interest rate during the period ended ​ — % 0.9 % Interest rate at end of the period ​ — % — % (1) Excludes $2.6 million and $2.6 million of letters of credit at March 31, 2022 and December 31, 2021, respectively .
Working capital credit facility
Unsecured Debt
Schedule of short-term debt	The following is a summary of short-term bank borrowings under the Working Capital Credit Facility at March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Total working capital credit facility ​ $ 75,000 ​ $ 75,000 ​ Borrowings outstanding at end of period ​ 37,194 ​ 29,546 ​ Weighted average daily borrowings during the period ended ​ 11,315 ​ 10,473 ​ Maximum daily borrowings during the period ended ​ 39,533 ​ 46,038 ​ Weighted average interest rate during the period ended ​ 1.0 % 0.9 % Interest rate at end of the period ​ 1.2 % 0.9 %

INCOME (LOSS) PER SHARE (Tables

INCOME (LOSS) PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2022
INCOME/(LOSS) PER SHARE
Computation of basic and diluted income/(loss) per share	The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ 2022 2021 ​ Numerator for income/(loss) per share: ​ ​ ​ ​ ​ ​ Net income/(loss) ​ $ 14,603 ​ $ 3,274 ​ Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (879) ​ (154) ​ Net (income)/loss attributable to noncontrolling interests ​ (19) ​ (16) ​ Net income/(loss) attributable to UDR, Inc. ​ 13,705 ​ 3,104 ​ Distributions to preferred stockholders — Series E (Convertible) ​ (1,092) ​ (1,056) ​ Income/(loss) attributable to common stockholders - basic and diluted ​ $ 12,613 ​ $ 2,048 ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator for income/(loss) per share: ​ ​ ​ Weighted average common shares outstanding ​ 318,293 ​ 296,800 ​ Non-vested restricted stock awards ​ (284) ​ (263) ​ Denominator for basic income/(loss) per share ​ 318,009 ​ 296,537 ​ Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, unvested restricted stock and shares issuable upon settlement of forward sales agreements ​ 1,671 ​ 489 ​ Denominator for diluted income/(loss) per share ​ 319,680 ​ 297,026 ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) per weighted average common share: ​ ​ ​ Basic ​ $ 0.04 ​ $ 0.01 ​ Diluted ​ $ 0.04 ​ $ 0.01 ​
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following table sets forth the additional shares of common stock outstanding, by equity instrument, if converted to common stock for each of the three months ended March 31, 2022 and 2021 (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ ​ 2022 ​ 2021 ​ OP/DownREIT Units 21,534 22,398 Convertible preferred stock 2,918 2,918 Unvested LTIP Units and unvested restricted stock 1,671 489

NONCONTROLLING INTERESTS (Table

NONCONTROLLING INTERESTS (Tables)	3 Months Ended
	Mar. 31, 2022
NONCONTROLLING INTERESTS
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	The following table sets forth redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership for the following period ( dollars in thousands ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, December 31, 2021 $ 1,299,442 ​ Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (43,747) ​ Conversion of OP Units/DownREIT Units to Common Stock or Cash ​ (23,944) ​ Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ 879 ​ Distributions to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (8,383) ​ Redeemable Long-Term Incentive Plan Units ​ ​ 37,383 ​ Allocation of other comprehensive income/(loss) ​ 514 ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, March 31, 2022 ​ $ 1,262,144 ​

FAIR VALUE OF DERIVATIVES AND_2

FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2022
FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS
Schedule of estimated fair values	The estimated fair values of the Company’s financial instruments either recorded or disclosed on a recurring basis as of March 31, 2022 and December 31, 2021, are summarized as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at March 31, 2022, Using ​ ​ Total ​ ​ ​ Quoted ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ Prices in ​ ​ ​ ​ ​ ​ Amount in ​ ​ ​ Active ​ ​ ​ ​ ​ ​ ​ Statement of ​ ​ ​ ​ Markets ​ Significant ​ ​ ​ ​ ​ Financial ​ Fair Value ​ for Identical ​ Other ​ Significant ​ ​ Position at ​ Estimate at ​ Assets or ​ Observable ​ Unobservable ​ ​ March 31, ​ March 31, ​ Liabilities ​ Inputs ​ Inputs ​ ​ 2022 (a) ​ 2022 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 26,577 ​ $ 26,818 ​ $ — ​ $ — ​ $ 26,818 Equity securities (c) ​ ​ 7,336 ​ ​ 7,336 ​ ​ 7,336 ​ ​ — ​ ​ — Derivatives - Interest rate contracts (d) ​ 10,488 ​ 10,488 ​ — ​ 10,488 ​ — Total assets ​ $ 44,401 ​ $ 44,642 ​ $ 7,336 ​ $ 10,488 ​ $ 26,818 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,032,370 ​ $ 978,793 ​ $ — ​ $ — ​ $ 978,793 Secured debt instruments - variable rate: (e) ​ ​ ​ ​ ​ ​ Tax-exempt secured notes payable ​ 27,000 ​ 27,000 ​ — ​ — ​ 27,000 Unsecured debt instruments: (e) ​ ​ ​ ​ ​ ​ Working capital credit facility ​ ​ 37,194 ​ ​ 37,194 ​ ​ — ​ ​ — ​ ​ 37,194 Commercial paper program ​ ​ 280,000 ​ ​ 280,000 ​ ​ — ​ ​ — ​ ​ 280,000 Unsecured notes ​ ​ 4,132,574 ​ ​ 3,876,882 ​ ​ — ​ ​ — ​ ​ 3,876,882 Total liabilities ​ $ 5,509,138 ​ $ 5,199,869 ​ $ — ​ $ — ​ $ 5,199,869 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 1,262,144 ​ $ 1,262,144 ​ $ — ​ $ 1,262,144 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at December 31, 2021, Using ​ ​ Total ​ ​ ​ Quoted ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ Prices in ​ ​ ​ ​ ​ ​ Amount in ​ ​ ​ Active ​ ​ ​ ​ ​ ​ Statement of ​ ​ ​ Markets ​ Significant ​ ​ ​ ​ Financial ​ Fair Value ​ for Identical ​ Other ​ Significant ​ ​ Position at ​ Estimate at ​ Assets or ​ Observable ​ Unobservable ​ ​ December 31, ​ December 31, ​ Liabilities ​ Inputs ​ Inputs ​ 2021 (a) ​ 2021 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 26,860 ​ $ 27,372 ​ $ — ​ $ — ​ $ 27,372 Equity securities (c) ​ ​ 3,230 ​ ​ 3,230 ​ ​ — ​ ​ — ​ ​ 3,230 Derivatives - Interest rate contracts (d) ​ 3,279 ​ 3,279 ​ — ​ 3,279 ​ — Total assets ​ $ 33,369 ​ $ 33,881 ​ $ — ​ $ 3,279 ​ $ 30,602 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,033,764 ​ $ 1,032,582 ​ $ — ​ $ — ​ $ 1,032,582 Secured debt instruments - variable rate: (e) ​ ​ ​ ​ ​ ​ Tax-exempt secured notes payable ​ 27,000 ​ 27,000 ​ — ​ — ​ 27,000 Unsecured debt instruments: (e) ​ ​ ​ ​ ​ ​ ​ Working capital credit facility ​ ​ 29,546 ​ ​ 29,546 ​ ​ — ​ ​ — ​ ​ 29,546 Commercial paper program ​ ​ 220,000 ​ ​ 220,000 ​ ​ — ​ ​ — ​ ​ 220,000 Unsecured notes ​ ​ 4,133,083 ​ ​ 4,199,363 ​ ​ — ​ ​ — ​ ​ 4,199,363 Total liabilities ​ $ 5,443,393 ​ $ 5,508,491 ​ $ — ​ $ — ​ $ 5,508,491 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 1,299,442 ​ $ 1,299,442 ​ $ — ​ $ 1,299,442 ​ $ — (a) Certain balances include fair market value adjustments and exclude deferred financing costs. (b) See Note 2, Significant Accounting Policies . (c) The Company holds a direct investment in a publicly traded real estate technology company, SmartRent, that was previously subject to a lock-up restriction on selling or transferring the investment, which expired in February 2022. The investment is valued at the market price on March 31, 2022 and as of December 31, 2021, was valued at the market price on December 31, 2021 less an illiquidity discount of 15.0% . Since the lock-up restriction expired, the Company currently classifies the investment as Level 1 in the fair value hierarchy. The Company previously classified the investment as Level 3 in the fair value hierarchy based upon the lock-up restriction. During the three months ended March 31, 2022, the Company increased its direct investment in SmartRent through a stock distribution from its unconsolidated real estate technology investments. (d) See Note 11, Derivatives and Hedging Activity . (e) See Note 7, Secured and Unsecured Debt, Net . (f) See Note 9, Noncontrolling Interests.

DERIVATIVES AND HEDGING ACTIV_2

DERIVATIVES AND HEDGING ACTIVITY (Tables)	3 Months Ended
	Mar. 31, 2022
DERIVATIVES AND HEDGING ACTIVITY
Schedule of outstanding interest rate derivatives	As of March 31, 2022, the Company had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ Number of ​ Product ​ Instruments ​ Notional Interest rate swaps and caps (a) ​ 4 ​ $ 334,880 (a) In addition to the interest rate swaps summarized above, the Company entered into two additional interest rate swaps with a total notional value of $175.0 million that will become effective in July 2022 upon maturity of the $315.0 million of the notional value of the interest rate swaps included above.
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheets	The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of March 31, 2022 and December 31, 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asset Derivatives ​ Liability Derivatives ​ ​ (included in Other assets ) ​ (included in Other liabilities ) ​ ​ Fair Value at: ​ Fair Value at: ​ ​ March 31, ​ December 31, ​ March 31, ​ December 31, ​ ​ 2022 ​ 2021 ​ 2022 ​ 2021 Derivatives designated as hedging instruments: ​ ​ ​ ​ Interest rate products ​ $ 10,488 ​ $ 3,279 ​ $ — ​ $ —
Effect of Company's derivative financial instruments on Consolidated Statements of Operations	The tables below present the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the three months ended March 31, 2022 and 2021 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain/(Loss) Recognized in ​ ​ ​ ​ Gain/(Loss) Reclassified ​ Interest expense ​ ​ Unrealized holding gain/(loss) ​ from Accumulated OCI into ​ (Amount Excluded from ​ ​ Recognized in OCI ​ Interest expense ​ Effectiveness Testing) Derivatives in Cash Flow Hedging Relationships 2022 2021 2022 2021 2022 2021 Three Months Ended March 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate products ​ $ 7,193 ​ $ 127 ​ $ (387) ​ $ (446) ​ $ — ​ $ —
Effect of Company's derivatives not designated as hedging instruments on the Consolidated Statements of Operations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ ​ 2022 ​ 2021 Total amount of Interest expense ​ $ 35,916 ​ $ 78,156 ​
Offsetting of Derivative Assets	The Company has elected not to offset derivative positions on the consolidated financial statements. The tables below present the effect on its financial position had the Company made the election to offset its derivative positions as of March 31, 2022 and December 31, 2021 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Net Amounts of Gross Amounts Not Offset ​ ​ ​ ​ ​ ​ ​ ​ Amounts ​ Assets ​ in the Consolidated ​ ​ ​ ​ ​ Gross ​ Offset in the ​ Presented in the ​ Balance Sheets ​ ​ ​ ​ ​ Amounts of ​ Consolidated ​ Consolidated ​ ​ ​ ​ Cash ​ ​ ​ ​ ​ Recognized ​ Balance ​ Balance Sheets ​ Financial ​ Collateral ​ ​ ​ Offsetting of Derivative Assets ​ Assets ​ Sheets ​ (a) ​ Instruments Received Net Amount March 31, 2022 ​ $ 10,488 ​ $ — ​ $ 10,488 ​ $ — ​ $ — ​ $ 10,488 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ $ 3,279 ​ $ — ​ $ 3,279 ​ $ — ​ $ — ​ $ 3,279 (a) Amounts reconcile to the aggregate fair value of derivative assets in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Consolidated Balance Sheets” located in this footnote.
Offsetting of Derivative Liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Net Amounts of Gross Amounts Not Offset ​ ​ ​ ​ ​ ​ ​ ​ Amounts ​ Liabilities ​ in the Consolidated ​ ​ ​ ​ ​ Gross ​ Offset in the ​ Presented in the ​ Balance Sheets ​ ​ ​ ​ ​ Amounts of ​ Consolidated ​ Consolidated ​ ​ ​ ​ Cash ​ ​ ​ ​ ​ Recognized ​ Balance ​ Balance Sheets ​ Financial ​ Collateral ​ ​ ​ Offsetting of Derivative Liabilities Liabilities Sheets (a) Instruments Posted Net Amount March 31, 2022 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — (a) Amounts reconcile to the aggregate fair value of derivative liabilities in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Consolidated Balance Sheets” located in this footnote.

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
	Mar. 31, 2022
COMMITMENTS AND CONTINGENCIES
Summary of real estate commitments	The following summarizes the Company’s real estate commitments at March 31, 2022 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number ​ UDR's ​ UDR's Remaining ​ ​ ​ Properties ​ Investment (a) ​ Commitment ​ Wholly-owned — under development 7 ​ $ 458,111 ​ $ 230,889 Joint ventures: ​ ​ Preferred equity investments 3 ​ ​ 76,382 (b) ​ 24,691 (b) Real estate technology investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ RETV I (c) ​ - ​ ​ 51,912 ​ ​ 5,220 ​ RETV II ​ - ​ ​ 7,818 ​ ​ 10,800 ​ RET Strategic Fund ​ - ​ ​ 7,517 ​ ​ 17,500 ​ Climate Technology Funds (d) ​ - ​ ​ 5,721 ​ ​ 4,279 ​ Total ​ $ 607,461 ​ $ 293,379 (a) Represents UDR’s investment as of March 31, 2022. (b) Represents UDR’s investment in and remaining commitment for Makers Rise, Infield Phase I and Upton Place, which are under development as of March 31, 2022. (c) Includes the impact of unrealized losses for the three months ended March 31, 2022, which primarily relate to a decrease in SmartRent's public share price . (See Note 5, Joint Ventures and Partnerships). (d) In March 2022, the Company committed to invest $10.0 million in climate technology funds and funded $5.7 million. As of March 31, 2022, the investment is recorded in Other Assets on the Consolidated Balance Sheets.

REPORTABLE SEGMENTS (Tables)

REPORTABLE SEGMENTS (Tables)	3 Months Ended
	Mar. 31, 2022
REPORTABLE SEGMENTS
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to Net income/(loss)	The following table details rental income and NOI for UDR’s reportable segments for the three months ended March 31, 2022 and 2021, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, (a) ​ 2022 2021 Reportable apartment home segment lease revenue ​ ​ ​ ​ ​ ​ Same-Store Communities (a) ​ ​ ​ West Region ​ $ 111,649 ​ $ 99,766 Mid-Atlantic Region ​ 65,820 ​ 61,847 Northeast Region ​ 64,412 ​ 58,287 Southeast Region ​ 44,322 ​ 38,767 Southwest Region ​ 26,047 ​ 23,211 Non-Mature Communities/Other ​ 33,457 ​ 9,569 Total segment and consolidated lease revenue ​ $ 345,707 ​ $ 291,447 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment other revenue ​ ​ ​ ​ ​ ​ Same-Store Communities (a) ​ ​ ​ West Region ​ $ 2,960 ​ $ 2,710 Mid-Atlantic Region ​ 2,363 ​ 1,909 Northeast Region ​ 1,257 ​ 1,103 Southeast Region ​ 1,792 ​ 1,635 Southwest Region ​ 892 ​ 875 Non-Mature Communities/Other ​ 1,210 ​ 147 Total segment and consolidated other revenue ​ $ 10,474 ​ $ 8,379 ​ ​ ​ ​ ​ ​ ​ Total reportable apartment home segment rental income ​ ​ ​ ​ ​ ​ Same-Store Communities (a) ​ ​ ​ West Region ​ $ 114,609 ​ $ 102,476 Mid-Atlantic Region ​ 68,183 ​ 63,756 Northeast Region ​ 65,669 ​ 59,390 Southeast Region ​ 46,114 ​ 40,402 Southwest Region ​ 26,939 ​ 24,086 Non-Mature Communities/Other ​ 34,667 ​ 9,716 Total segment and consolidated rental income ​ $ 356,181 ​ $ 299,826 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment NOI ​ ​ Same-Store Communities (a) ​ ​ West Region ​ $ 85,636 ​ $ 74,593 Mid-Atlantic Region ​ 46,983 ​ 43,620 Northeast Region ​ 42,083 ​ 36,328 Southeast Region ​ 31,461 ​ 26,645 Southwest Region ​ 17,339 ​ 14,835 Non-Mature Communities/Other ​ 20,431 ​ 5,037 Total segment and consolidated NOI ​ 243,933 ​ 201,058 Reconciling items: ​ ​ Joint venture management and other fees ​ 1,085 ​ 1,615 Property management ​ (11,576) ​ (8,995) Other operating expenses ​ (4,712) ​ (4,435) Real estate depreciation and amortization ​ (163,622) ​ (144,088) General and administrative ​ (14,908) ​ (12,736) Casualty-related (charges)/recoveries, net ​ 765 ​ (5,577) Other depreciation and amortization ​ (3,075) ​ (2,601) Gain/(loss) on sale of real estate owned ​ ​ — ​ ​ 50,829 Income/(loss) from unconsolidated entities ​ 5,412 ​ 4,922 Interest expense ​ (35,916) ​ (78,156) Interest income and other income/(expense), net ​ (2,440) ​ 2,057 Tax (provision)/benefit, net ​ (343) ​ (619) Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (879) ​ (154) Net (income)/loss attributable to noncontrolling interests ​ (19) ​ (16) Net income/(loss) attributable to UDR, Inc. ​ $ 13,705 ​ $ 3,104 (a) Same-Store Community population consisted of 47,443 apartment homes. ​
Details of assets of UDR's reportable segments	The following table details the assets of UDR’s reportable segments as of March 31, 2022 and December 31, 2021 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2022 ​ 2021 Reportable apartment home segment assets: ​ ​ Same-Store Communities (a): ​ ​ West Region ​ $ 4,301,470 ​ $ 4,288,116 Mid-Atlantic Region ​ 2,863,633 ​ 2,856,144 Northeast Region ​ 3,342,355 ​ 3,338,497 Southeast Region ​ 1,212,612 ​ 1,208,183 Southwest Region ​ 902,350 ​ 900,931 Non-Mature Communities/Other ​ 2,210,635 ​ 2,148,932 Total segment assets ​ 14,833,055 ​ 14,740,803 Accumulated depreciation ​ (5,289,853) ​ (5,137,096) Total segment assets — net book value ​ 9,543,202 ​ 9,603,707 Reconciling items: ​ ​ Cash and cash equivalents ​ 895 ​ 967 Restricted cash ​ 26,032 ​ 27,451 Notes receivable, net ​ 26,577 ​ 26,860 Investment in and advances to unconsolidated joint ventures, net ​ 669,343 ​ 702,461 Operating lease right-of-use assets ​ ​ 196,578 ​ ​ 197,463 Other assets ​ 222,337 ​ 216,311 Total consolidated assets ​ $ 10,684,964 ​ $ 10,775,220 (a) Same-Store Community population consisted of 47,443 apartment homes. ​

BASIS OF PRESENTATION (Details)

BASIS OF PRESENTATION (Details) shares in Millions	3 Months Ended
	Mar. 31, 2022itemcommunityhomeshares
Consolidation And Basis Of Presentation
Number of Real Estate Properties | community	160
Number of Markets Operating Within | item	21
Number Of Apartment Homes Owned And Consolidated By Company | home	53,503
Joint venture, number of completed or to be completed homes in communities | home	6,489
Preferred equity investment,, number of apartment homes | home	3,652
Operating Partnership outstanding units	186.2
United Dominion Reality L.P.
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner	176.3
General Partnership units outstanding	0.1
General Partners' ownership (as a percent)	94.70%
UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating Partnership outstanding units	32.4
Non-affiliated Partners
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner	9.9
Percentage of units outstanding in Partnership	5.30%
Non-affiliated Partners | UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating Partnership outstanding units	11.6
Percentage of units outstanding in Partnership	35.80%
UDR, Inc.
Consolidation And Basis Of Presentation
General Partners' ownership (as a percent)	64.20%
Operating Partnership outstanding units	20.8

SIGNIFICANT ACCOUNTING POLICI_4

SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Significant Accounting Policies
Note receivable interest income	$ 700	$ 1,900
Interest income, related party	0	0
Allocation of other comprehensive income/(loss)	514
Current income tax expense (benefit)	0
Net deferred tax assets/(liabilities)	(800)		$ (800)
Unrecognized tax benefit, accrued interest or penalties due to examination	0
Adjustment to rental income	2,300
Adjustment to income (loss)	200
Noncontrolling Interest
Significant Accounting Policies
Allocation of other comprehensive income/(loss)	500
Maximum
Accounting policies
Credit losses	100	100
Maximum | Noncontrolling Interest
Significant Accounting Policies
Allocation of other comprehensive income/(loss)		$ 100
Multifamily tenant lease
Significant Accounting Policies
Increase (decrease) in reserves	(1,300)
Retail tenant lease
Significant Accounting Policies
Increase (decrease) in reserves	$ (1,200)

SIGNIFICANT ACCOUNTING POLICI_5

SIGNIFICANT ACCOUNTING POLICIES - Notes Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Accounting Policies [Line Items]
Notes receivable	$ 26,710	$ 26,995
Allowance for credit losses	(133)	(135)
Notes receivable, net	26,577	26,860
Total real estate, net	9,543,202	9,603,707
Unpaid accrued interest	25,700	45,980
Note due May 2022
Accounting Policies [Line Items]
Notes receivable		2,760
Aggregate Commitment on Note Receivable	2,800
Note due January 2023
Accounting Policies [Line Items]
Notes receivable	$ 26,710	24,235
Note Receivable Interest Rate	10.00%
Aggregate Commitment on Note Receivable	$ 30,400	$ 25,400
Note maturity public capital threshold	$ 5,000

REAL ESTATE OWNED - Summarizes

REAL ESTATE OWNED - Summarizes the carrying amounts for our real estate owned (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Real estate owned
Land	$ 2,325,852	$ 2,342,385
Depreciable property - held and used:
Land improvements	242,835	241,905
Building, improvements, and furniture, fixtures and equipment	11,756,244	11,717,931
Real estate intangible assets	50,013	50,013
Under development:
Real estate under development	457,160	388,062
Real estate owned	14,833,055	14,740,803
Accumulated depreciation	(5,289,853)	(5,137,096)
Total real estate owned, net of accumulated depreciation	9,543,202	9,603,707
Accumulated amortization	10,200	8,800
Land and land improvements
Under development:
Real estate under development	90,932	74,399
Building, improvements and furniture, fixtures and equipment
Under development:
Real estate under development	$ 367,179	$ 314,170

REAL ESTATE OWNED - Additional

REAL ESTATE OWNED - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)homestatecommunity	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Real Estate Owned Disclosure
Number of real estate properties | community	160
Number of states in which there are owned and consolidated communities | state	13
Financing Receivable, before Allowance for Credit Loss	$ 26,710		$ 26,995
Number of apartment homes owned and consolidated | home	53,503
Investment in unconsolidated entities	$ 662,964		696,376
Gain/(loss) on sale of real estate		$ 50,829
Total real estate, net	9,543,202		9,603,707
Debt premium	25,900		27,000
Gain on extinguishment of debt		(41,950)
In-place intangibles	50,013		50,013
Long-term Debt	5,466,320
Development costs excluding direct costs and capitalized interest	5,400	4,600
Interest capitalized during period	3,200	$ 2,100
Note due May 2022
Real Estate Owned Disclosure
Financing Receivable, before Allowance for Credit Loss			$ 2,760
Amount of a promissory note	$ 2,800

JOINT VENTURES AND PARTNERSHI_3

JOINT VENTURES AND PARTNERSHIPS - Summary (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)homecommunityproperty	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Unconsolidated entities
Number of real estate properties | community	160
Investment in unconsolidated entities	$ 662,964		$ 696,376
Sold joint ventures and other investments		$ 3,008
Income/(loss) from investments	$ 5,412	4,922
Preferred Equity Investment Meetinghouse Portland, OR
Unconsolidated entities
Number of apartment homes | home	232
Investment in unconsolidated entities	$ 11,600
Rate	8.25%
Operating Community
Unconsolidated entities
Investment in unconsolidated entities	$ 264,392		270,915
Income/(loss) from investments	$ (2,638)	(6,541)
Operating Community | Unconsolidated Joint Venture UDR Met Life I Partnership [Member]
Unconsolidated entities
Number of real estate properties | property	1
Number of apartment homes | home	150
Investment in unconsolidated entities	$ 22,936		$ 23,880
UDR's Ownership Interest	50.00%		50.00%
Income/(loss) from investments	$ (625)	(475)
Operating Community | Unconsolidated Joint Venture UDR MetLife II Partnership [Member]
Unconsolidated entities
Number of real estate properties | property	7
Number of apartment homes | home	1,250
Investment in unconsolidated entities	$ 179,223		$ 181,023
UDR's Ownership Interest	50.00%		50.00%
Income/(loss) from investments	$ 100	(2,684)
Operating Community | Unconsolidated Joint Venture Other MetLife
Unconsolidated entities
Number of real estate properties | property	5
Number of apartment homes | home	1,437
Investment in unconsolidated entities	$ 62,233		$ 66,012
UDR's Ownership Interest	50.60%		50.60%
Income/(loss) from investments	$ (2,113)	(3,382)
Development Community | Preferred Equity Investment 1532 Harrison San Francisco, CA
Unconsolidated entities
Investment in unconsolidated entities	34,945		$ 35,248
UDR Commitment	$ 24,645
Rate	11.00%
Years to Maturity	2 months 12 days
Income/(loss) from investments	$ (6)	929
Development Community | Preferred Equity Investment 1641 Lincoln Santa Monica CA
Unconsolidated entities
Investment in unconsolidated entities	13,577		13,183
UDR Commitment	$ 8,800
Rate	12.00%
Years to Maturity	3 months 18 days
Income/(loss) from investments	$ 394	350
Development Community | Preferred Equity Investment 1200 Broadway Nashville TN
Unconsolidated entities
Investment in unconsolidated entities			61,326
Income/(loss) from investments	11,893	1,372
Development Community | Preferred Equity Investment 1300 Fairmount Philadelphia, PA
Unconsolidated entities
Investment in unconsolidated entities	66,146		64,780
UDR Commitment	$ 51,393
Rate	8.50%
Years to Maturity	1 year 4 months 24 days
Income/(loss) from investments	$ 1,366	1,255
Development Community | Preferred Equity Investment Modera Lake Merritt, Oakland
Unconsolidated entities
Investment in unconsolidated entities	34,584		33,828
UDR Commitment	$ 27,250
Rate	9.00%
Years to Maturity	2 years
Income/(loss) from investments	$ 756	691
Development Community | Preferred Equity Investment Thousand Oaks, CA
Unconsolidated entities
Investment in unconsolidated entities	23,272		22,764
UDR Commitment	$ 20,059
Rate	9.00%
Years to Maturity	2 years 10 months 24 days
Income/(loss) from investments	$ 508	438
Development Community | Preferred Equity Investment Queens, New York
Unconsolidated entities
Investment in unconsolidated entities	49,771		48,210
UDR Commitment	$ 40,000
Rate	13.00%
Years to Maturity	3 years 3 months 18 days
Income/(loss) from investments	$ 1,561	1,372
Development Community | Preferred Equity Investment Herndon, Virginia
Unconsolidated entities
Investment in unconsolidated entities	31,583		22,828
UDR Commitment	$ 30,208
Rate	9.00%
Years to Maturity	3 years 9 months 18 days
Income/(loss) from investments	$ 644	96
Development Community | Preferred Equity Investment Allen, Texas
Unconsolidated entities
Investment in unconsolidated entities	21,045		14,134
UDR Commitment	$ 19,843
Rate	9.00%
Years to Maturity	3 years 10 months 24 days
Income/(loss) from investments	$ 394	2
Development Community | Preferred Equity Investment Infield Phase I
Unconsolidated entities
Investment in unconsolidated entities	7,567
UDR Commitment	$ 16,044
Rate	14.00%
Years to Maturity	2 years 1 month 6 days
Income/(loss) from investments	$ 86
Development Community | Preferred Equity Investment Upton Place, Washington, D C [Member]
Unconsolidated entities
Investment in unconsolidated entities	37,232		29,566
UDR Commitment	$ 52,163
Rate	9.70%
Years to Maturity	5 years 8 months 12 days
Income/(loss) from investments	$ 676
Development Community | Preferred Equity Investment Meetinghouse Portland, OR
Unconsolidated entities
Investment in unconsolidated entities	11,603
UDR Commitment	$ 11,600
Rate	8.25%
Years to Maturity	4 years 10 months 24 days
Income/(loss) from investments	$ 3
Development Community | Real estate technology investments RETV I
Unconsolidated entities
Investment in unconsolidated entities	51,912		71,464
UDR Commitment	18,000
Income/(loss) from investments	(10,111)	2,051
Development Community | Real estate technology investments RETV II
Unconsolidated entities
Investment in unconsolidated entities	7,818		8,130
UDR Commitment	18,000
Income/(loss) from investments	(114)	(101)
Development Community | Real estate technology investments RETV Strategic Fund
Unconsolidated entities
Investment in unconsolidated entities	7,517
UDR Commitment	25,000
Development Community | Preferred Equity Investments and Real Estate Technology Investments
Unconsolidated entities
Investment in unconsolidated entities	398,572		$ 425,461
Income/(loss) from investments	$ 8,050	$ 8,455

JOINT VENTURES AND PARTNERSHI_4

JOINT VENTURES AND PARTNERSHIPS - Commitments (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Jan. 31, 2022USD ($)home	Mar. 31, 2022USD ($)home	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)
Joint Ventures
Investment in unconsolidated entities		$ 662,964		$ 696,376
Gain/(loss) on sale of real estate owned			$ 50,829
Deferred fees from the sale of properties		7,700		8,700
Joint venture management and other fees		$ 1,085	$ 1,615
Type of revenue		udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
Limited Partner
Joint Ventures
Investment in unconsolidated entities	$ 7,500
UDR Commitment	$ 25,000
Operating Community
Joint Ventures
Investment in unconsolidated entities		$ 264,392		270,915
Unconsolidated Joint Venture UDR Met Life I Partnership [Member] | Operating Community
Joint Ventures
Investment in unconsolidated entities		$ 22,936		23,880
Number of apartment homes | home		150
Unconsolidated Joint Venture UDR MetLife II Partnership [Member] | Operating Community
Joint Ventures
Investment in unconsolidated entities		$ 179,223		181,023
Number of apartment homes | home		1,250
Preferred Equity Investment Herndon, Virginia | Development Community
Joint Ventures
Investment in unconsolidated entities		$ 31,583		22,828
UDR Commitment		$ 30,208
Preferred return (as a percent)		9.00%
Preferred Equity Investment Allen, Texas | Development Community
Joint Ventures
Investment in unconsolidated entities		$ 21,045		14,134
UDR Commitment		$ 19,843
Preferred return (as a percent)		9.00%
Preferred Equity Investment 1200 Broadway Nashville TN | Development Community
Joint Ventures
Investment in unconsolidated entities				61,326
Real estate technology investments RETV I | Development Community
Joint Ventures
Investment in unconsolidated entities		$ 51,912		71,464
UDR Commitment		18,000
Accounts Payable, Accrued Expenses and Other Liabilities | 13th and Market Properties LLC
Joint Ventures
Investment in unconsolidated entities		$ (6,400)		$ (6,100)
Preferred Equity Investment Home Operating Community, Nashville Tennessee [Member] | Operating Community
Joint Ventures
Number of communities sold | home	313
Equity method investment amount sold	$ 294,000
Variable participation on the sale of community	$ 10,600

JOINT VENTURES AND PARTNERSHI_5

JOINT VENTURES AND PARTNERSHIPS - Unconsolidated joint ventures and partnerships (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Financial information relating to unconsolidated joint ventures operations
Total revenues	$ 357,266	$ 301,441
Property operating expenses	58,484	51,381
Real estate depreciation and amortization	163,622	144,088
Gain/(loss) on sale of real estate		50,829
Operating income	47,890	75,070
Interest expense	(35,916)	(78,156)
Other income/(loss)	(2,440)	2,057
Net income/(loss)	14,603	3,274
Combined summary of balance sheets relating to unconsolidated joint ventures
Total real estate, net	9,543,202		$ 9,603,707
Investments, at fair value	669,343		702,461
Cash and cash equivalents	895	1,172	967	$ 1,409
Other Assets	222,337		216,311
Total assets	10,684,964		10,775,220
Accounts payable, accrued expenses, and other liabilities	117,240		136,954
Total liabilities	6,029,937		6,001,474
Total equity	3,392,883	3,016,401	3,474,304	$ 3,258,591
Unconsolidated Joint Ventures
Financial information relating to unconsolidated joint ventures operations
Total revenues	37,169	32,137
Property operating expenses	17,930	17,110
Real estate depreciation and amortization	17,820	16,453
Gain/(loss) on sale of real estate	127,542	34,757
Operating income	128,961	33,331
Interest expense	(8,132)	(12,134)
Other income/(loss)	(224)	(1,657)
Net realized/unrealized gain/(loss) on held investments	6,304	2,494
Net realized gain/(loss) on held investments	(21,492)	5,994
Net income/(loss)	105,417	$ 28,028
Combined summary of balance sheets relating to unconsolidated joint ventures
Total real estate, net	2,121,264		2,043,158
Investments, at fair value	383,143		460,241
Real estate assets held for sale			168,668
Cash and cash equivalents	31,328		22,891
Other Assets	24,494		28,948
Total assets	2,560,229		2,723,906
Third party debt, net	1,245,610		1,215,918
Liabilities held for sale			106,990
Accounts payable, accrued expenses, and other liabilities	75,487		51,689
Total liabilities	1,321,097		1,374,597
Total equity	$ 1,239,132		$ 1,349,309

LEASES - Lessee Future Minimum

LEASES - Lessee Future Minimum Payments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)community	Dec. 31, 2021USD ($)
Lease expense:
Number of communities subject to ground leases | community	6
Operating leases existence of option to extend	true
Operating lease right-of-use assets	$ 196,578	$ 197,463
Weighted average remaining lease term	43 years 1 month 6 days	43 years 2 months 12 days
Weighted average discount rate	5.00%	5.00%
Future minimum lease payments
Total operating lease liabilities (discounted)	$ 191,689	$ 192,488
LAND
Future minimum lease payments
2022	9,331
2023	12,442
2024	12,442
2025	12,442
2026	12,442
Thereafter	430,337
Total future minimum lease payments (undiscounted)	489,436
Difference between future undiscounted cash flows and discounted cash flows	(297,747)
Total operating lease liabilities (discounted)	$ 191,689

LEASES - Lessee Expenses (Detai

LEASES - Lessee Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Lease expense:
Contractual lease expense	$ 100	$ 100
Variable lease expense	300	100
Operating lease right-of-use asset amortization	900	800
Operating lease liabilities amortization	800	800
LAND
Lease expense:
Contractual lease expense	3,311	3,230
Variable lease expense	26	29
LAND | Other operating expense
Lease expense:
Total operating lease expense	$ 3,337	$ 3,259

LEASES - Lessor (Details)

LEASES - Lessor (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Future minimum lease payments
Variable lease expense	$ 300	$ 100
Minimum
Lessor leases
Percentage of lease revenue	1.00%
Maximum
Lessor leases
Percentage of lease revenue	2.00%
LAND
Future minimum lease payments
Variable lease expense	$ 26	$ 29
Apartment Homes
Lessor leases
Option to extend	true
Apartment Homes | Maximum
Lessor leases
Lease terms	12 months
Retail and Commercial Spaces
Lessor leases
Option to extend	true
Future minimum lease payments
2022	$ 18,504
2023	24,186
2024	22,012
2025	18,834
2026	16,028
Thereafter	68,924
Total future minimum payments	$ 168,488
Retail and Commercial Spaces | Minimum
Lessor leases
Lease terms	5 years
Retail and Commercial Spaces | Maximum
Lessor leases
Lease terms	15 years

SECURED AND UNSECURED DEBT, N_3

SECURED AND UNSECURED DEBT, NET - Summary (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)community	Dec. 31, 2021USD ($)	Sep. 30, 2021USD ($)
Secured debt instruments
Total Debt, net	$ 5,479,010	$ 5,412,787
Long-term Debt	5,466,320
Unamortized net premium	$ 25,900	27,000
Weighted average interest rate (as a percent)	2.80%
Weighted Average
Secured debt instruments
Years to maturity	7 years 4 months 24 days
3.00% Medium-Term Notes due August 2031
Secured debt instruments
Long-term Debt			$ 600,000
Secured Debt
Secured debt instruments
Total Debt, net	$ 1,056,110	1,057,380
Long-term Debt	$ 1,033,482
Weighted average interest rate (as a percent)	3.35%
Number of Communities Encumbered | community	15
Secured Debt | Weighted Average
Secured debt instruments
Years to maturity	6 years 3 months 18 days
Unsecured Debt
Secured debt instruments
Total Debt, net	$ 4,422,900	4,355,407
Long-term Debt	$ 4,432,838
Weighted average interest rate (as a percent)	2.71%
Deferred finance costs, net	$ (26,868)	(27,222)
Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	7 years 8 months 12 days
Fixed Rate Debt | Secured Debt
Secured debt instruments
Total Debt, net	$ 1,029,168
Long-term Debt	1,006,482
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable
Secured debt instruments
Total Debt, net	1,006,482	1,006,762
Deferred financing costs and other non-cash adjustments	(22,686)	(23,678)
Long-term Debt	$ 1,029,168	1,030,440
Weighted average interest rate (as a percent)	3.42%
Number of Communities Encumbered | community	14
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable | Weighted Average
Secured debt instruments
Years to maturity	6 years 2 months 12 days
Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Unamortized discount	$ 4	4
Fixed Rate Debt | Unsecured Debt | Term Loan due January 2027
Secured debt instruments
Long-term Debt	$ 315,000	315,000
Weighted average interest rate (as a percent)	1.02%
Fixed Rate Debt | Unsecured Debt | Term Loan due January 2027 | Weighted Average
Secured debt instruments
Years to maturity	4 years 9 months 18 days
Fixed Rate Debt | Unsecured Debt | 8.50% Debentures, Due September 2024
Secured debt instruments
Long-term Debt	$ 15,644	$ 15,644
Stated interest rate	8.50%	8.50%
Weighted average interest rate (as a percent)	8.50%
Fixed Rate Debt | Unsecured Debt | 8.50% Debentures, Due September 2024 | Weighted Average
Secured debt instruments
Years to maturity	2 years 6 months
Fixed Rate Debt | Unsecured Debt | 2.95% Medium-Term Note due September 2026
Secured debt instruments
Long-term Debt	$ 300,000	$ 300,000
Stated interest rate	2.95%	2.95%
Weighted average interest rate (as a percent)	2.89%
Fixed Rate Debt | Unsecured Debt | 2.95% Medium-Term Note due September 2026 | Weighted Average
Secured debt instruments
Years to maturity	4 years 4 months 24 days
Fixed Rate Debt | Unsecured Debt | 3.50 Medium-Term Note due July 2027
Secured debt instruments
Total Debt, net	$ 299,630	$ 299,612
Stated interest rate	3.50%	3.50%
Unamortized discount	$ 370	$ 388
Weighted average interest rate (as a percent)	4.03%
Fixed Rate Debt | Unsecured Debt | 3.50 Medium-Term Note due July 2027 | Weighted Average
Secured debt instruments
Years to maturity	5 years 3 months 18 days
Fixed Rate Debt | Unsecured Debt | 3.50% Medium-Term Notes Due January 2028
Secured debt instruments
Total Debt, net	$ 299,311	$ 299,283
Stated interest rate	3.50%	3.50%
Unamortized discount	$ 689	$ 717
Weighted average interest rate (as a percent)	3.50%
Fixed Rate Debt | Unsecured Debt | 3.50% Medium-Term Notes Due January 2028 | Weighted Average
Secured debt instruments
Years to maturity	5 years 9 months 18 days
Fixed Rate Debt | Unsecured Debt | 4.40% Medium-Term Notes due January 2029
Secured debt instruments
Total Debt, net	$ 299,996	$ 299,996
Stated interest rate	4.40%	4.40%
Weighted average interest rate (as a percent)	4.27%
Fixed Rate Debt | Unsecured Debt | 4.40% Medium-Term Notes due January 2029 | Weighted Average
Secured debt instruments
Years to maturity	6 years 9 months 18 days
Fixed Rate Debt | Unsecured Debt | 3.20% Medium-Term Notes due January 2030
Secured debt instruments
Total Debt, net	$ 610,697	$ 611,040
Stated interest rate	3.20%	3.20%
Unamortized discount	$ 10,697	$ 11,040
Weighted average interest rate (as a percent)	3.32%
Fixed Rate Debt | Unsecured Debt | 3.20% Medium-Term Notes due January 2030 | Weighted Average
Secured debt instruments
Years to maturity	7 years 9 months 18 days
Fixed Rate Debt | Unsecured Debt | 3.00% Medium-Term Notes due August 2031
Secured debt instruments
Total Debt, net	$ 611,200	$ 611,498
Stated interest rate	3.00%	3.00%
Unamortized discount		$ 11,498
Unamortized net premium	$ 11,200
Weighted average interest rate (as a percent)	3.01%
Fixed Rate Debt | Unsecured Debt | 3.00% Medium-Term Notes due August 2031 | Weighted Average
Secured debt instruments
Years to maturity	9 years 4 months 24 days
Fixed Rate Debt | Unsecured Debt | 2.10% Medium Term Note Due August 2032
Secured debt instruments
Total Debt, net	$ 399,636	399,627
Stated interest rate	2.10%
Unamortized discount	$ 364	373
Weighted average interest rate (as a percent)	2.10%
Fixed Rate Debt | Unsecured Debt | 2.10% Medium Term Note Due August 2032 | Weighted Average
Secured debt instruments
Years to maturity	10 years 3 months 18 days
Fixed Rate Debt | Unsecured Debt | 1.90% Medium-Term Notes due March 2033
Secured debt instruments
Total Debt, net	$ 348,679	$ 348,649
Stated interest rate	1.90%	1.90%
Unamortized discount	$ 1,321	$ 1,351
Weighted average interest rate (as a percent)	1.90%
Fixed Rate Debt | Unsecured Debt | 1.90% Medium-Term Notes due March 2033 | Weighted Average
Secured debt instruments
Years to maturity	10 years 10 months 24 days
Fixed Rate Debt | Unsecured Debt | 2.10% Medium-Term Note due June 2033
Secured debt instruments
Total Debt, net	$ 298,885	$ 298,860
Stated interest rate	2.10%	2.10%
Unamortized discount	$ 1,115	$ 1,140
Weighted average interest rate (as a percent)	2.10%
Fixed Rate Debt | Unsecured Debt | 2.10% Medium-Term Note due June 2033 | Weighted Average
Secured debt instruments
Years to maturity	11 years 2 months 12 days
Fixed Rate Debt | Unsecured Debt | 3.10% Medium-Term Notes due November 2034
Secured debt instruments
Total Debt, net	$ 298,889	$ 298,867
Stated interest rate	3.10%	3.10%
Unamortized discount	$ 1,111	$ 1,133
Weighted average interest rate (as a percent)	3.13%
Fixed Rate Debt | Unsecured Debt | 3.10% Medium-Term Notes due November 2034 | Weighted Average
Secured debt instruments
Years to maturity	12 years 7 months 6 days
Fixed Rate Debt | Unsecured Debt | Other [Member]
Secured debt instruments
Total Debt, net	$ 7	7
Variable Rate Debt | Secured Debt
Secured debt instruments
Total Debt, net	26,942
Long-term Debt	27,000
Variable Rate Debt | Secured Debt | Tax-exempt notes payable
Secured debt instruments
Total Debt, net	26,942	26,940
Long-term Debt	$ 27,000	27,000
Weighted average interest rate (as a percent)	0.87%
Number of Communities Encumbered | community	1
Deferred finance costs, net	$ (58)	(60)
Variable Rate Debt | Secured Debt | Tax-exempt notes payable | Weighted Average
Secured debt instruments
Years to maturity	10 years
Variable Rate Debt | Unsecured Debt | Commercial Paper
Secured debt instruments
Borrowings outstanding	$ 280,000	220,000
Weighted average interest rate (as a percent)	0.77%
Variable Rate Debt | Unsecured Debt | Commercial Paper | Weighted Average
Secured debt instruments
Years to maturity	1 month 6 days
Variable Rate Debt | Unsecured Debt | Unsecured Revolving Credit Facility Due January 2026 | Weighted Average
Secured debt instruments
Years to maturity	3 years 9 months 18 days
Variable Rate Debt | Unsecured Debt | Working capital credit facility
Secured debt instruments
Borrowings outstanding	$ 37,194	29,546
Weighted average interest rate (as a percent)	1.23%
Variable Rate Debt | Unsecured Debt | Working capital credit facility | Weighted Average
Secured debt instruments
Years to maturity	1 year 9 months 18 days
Variable Rate Debt | Unsecured Debt | Term Loan due January 2027
Secured debt instruments
Long-term Debt	$ 35,000	$ 35,000
Weighted average interest rate (as a percent)	1.08%
Variable Rate Debt | Unsecured Debt | Term Loan due January 2027 | Weighted Average
Secured debt instruments
Years to maturity	4 years 9 months 18 days

SECURED AND UNSECURED DEBT, N_4

SECURED AND UNSECURED DEBT, NET - Credit Facilities (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022USD ($)loan	Dec. 31, 2021USD ($)	Aug. 31, 2021USD ($)instrument	Nov. 30, 2020instrument
Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	85.00%
Revolving Credit Facility
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 1,300,000
Potential maximum available	$ 2,500,000
Number of Extensions of loan | loan	2
Extension period of option on loan	6 months
Revolving credit facility due 2023 | Letter of Credit
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Borrowings outstanding at end of period	$ 2,600	$ 2,600
Revolving credit facility due 2023 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Commitment fee	0.15%
Basis points added to to variable rate	0.775%
basis point subtracted from variable rate for Company receiving green building certifications	0.02%
Revolving credit facility due 2023 | Unsecured Debt | Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Commitment fee	0.10%
Basis points added to to variable rate	0.70%
Revolving credit facility due 2023 | Unsecured Debt | Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Commitment fee	0.30%
Basis points added to to variable rate	1.40%
Revolving credit facility due 2023 | Revolving Credit Facility
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 1,300,000	1,300,000
Weighted average daily borrowings during the period ended		13,068
Maximum daily borrowings during the period ended		$ 305,000
Weighted average interest rate during the period ended		0.90%
Term Loan due September 2023 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Number of interest rate swaps | instrument				3
All-in weighted average interest rate				1.02%
Term Loan due September 2023 | Unsecured Debt | Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.75%
Term Loan due September 2023 | Unsecured Debt | Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.60%
basis point subtracted from variable rate for Company receiving green building certifications	0.02%
Working capital credit facility | Variable Rate Debt | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 75,000	$ 75,000
Borrowings outstanding at end of period	37,194	29,546
Weighted average daily borrowings during the period ended	11,315	10,473
Maximum daily borrowings during the period ended	$ 39,533	$ 46,038
Weighted average interest rate during the period ended	1.00%	0.90%
Interest rate at end of the period	1.20%	0.90%
Basis points added to to variable rate	0.775%
Working capital credit facility | Variable Rate Debt | Unsecured Debt | Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.70%
Working capital credit facility | Variable Rate Debt | Unsecured Debt | Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.40%
Term Loan Facility Due January 2027
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 350,000
Term Loan Facility Due July 2025 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Notional			$ 175,000
Number of interest rate swaps | instrument			2
All-in weighted average interest rate			1.48%

SECURED AND UNSECURED DEBT, N_5

SECURED AND UNSECURED DEBT, NET - Short Term Debt (Details) - Variable Rate Debt - Unsecured Debt - Commercial Paper - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Unsecured Debt
Total unsecured commercial paper program	$ 700,000	$ 700,000
Borrowings outstanding at end of period	280,000	220,000
Weighted average daily borrowings during the period ended	280,722	419,563
Maximum daily borrowings during the period ended	$ 410,000	$ 700,000
Weighted average interest rate during the period ended	0.40%	0.20%
Interest rate at end of the period	0.80%	0.30%

SECURED AND UNSECURED DEBT, N_6

SECURED AND UNSECURED DEBT, NET - Unsecured Maturities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Aggregate maturities of unsecured debt
2022	$ 280,860
2023	1,242
2024	149,585
2025	174,793
2026	352,744
2027	652,860
2028	462,310
2029	491,986
2030	762,010
2031	760,930
Thereafter	1,377,000
Subtotal	5,466,320
Non-cash	12,690
Total	5,479,010		$ 5,412,787
Interest expense
Aggregate maturities of unsecured debt
Amortization of financing costs	900	$ 1,200
Secured Debt
Aggregate maturities of unsecured debt
2022	860
2023	1,242
2024	96,747
2025	174,793
2026	52,744
2027	2,860
2028	162,310
2029	191,986
2030	162,010
2031	160,930
Thereafter	27,000
Subtotal	1,033,482
Non-cash	22,628
Total	1,056,110		1,057,380
Secured Debt | Fixed Rate Debt
Aggregate maturities of unsecured debt
2022	860
2023	1,242
2024	96,747
2025	174,793
2026	52,744
2027	2,860
2028	162,310
2029	191,986
2030	162,010
2031	160,930
Subtotal	1,006,482
Non-cash	22,686
Total	1,029,168
Secured Debt | Variable Rate Debt
Aggregate maturities of unsecured debt
Thereafter	27,000
Subtotal	27,000
Non-cash	(58)
Total	26,942
Unsecured Debt
Aggregate maturities of unsecured debt
2022	280,000
2023	0
2024	52,838
2025	0
2026	300,000
2027	650,000
2028	300,000
2029	300,000
2030	600,000
2031	600,000
Thereafter	1,350,000
Subtotal	4,432,838
Non-cash	(9,938)
Total	$ 4,422,900		$ 4,355,407

SECURED AND UNSECURED DEBT, N_7

SECURED AND UNSECURED DEBT, NET - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Sep. 30, 2021	Jul. 31, 2020	Feb. 29, 2020
Secured Debt
Secured debt amount which encumbers real estate owned based upon book value	$ 1,700,000
Percentage of secured debt which encumbers real estate owned based upon book value	11.70%
Secured debt amount of real estate owned which is unencumbered	$ 13,100,000
Percentage of secured debt of real estate owned which is unencumbered	88.30%
Long-term Debt	$ 5,466,320
Extinguishment of debt costs		$ 40,769
Unamortized net premium	25,900		$ 27,000
3.00% Medium-Term Notes due August 2031
Secured Debt
Long-term Debt				$ 600,000
Interest rate risk				$ 250,000
All-in weighted average interest rate				3.01%
Unsecured Debt
Secured Debt
Long-term Debt	$ 4,432,838
Basis points added to to variable rate	85.00%
Secured Debt
Secured Debt
Long-term Debt	$ 1,033,482
Fixed Rate Debt | Mortgages Notes Payable | Minimum
Secured Debt
Notes payable maximum interest rates range	2.62%
Fixed Rate Debt | Mortgages Notes Payable | Maximum
Secured Debt
Notes payable maximum interest rates range	4.39%
Fixed Rate Debt | Unsecured Debt | 2.95% Medium-Term Note due September 2026
Secured Debt
Long-term Debt	$ 300,000		$ 300,000
Stated interest rate	2.95%		2.95%
Portion of medium term note subject to interest rate swaps	$ 100,000
All-in weighted average interest rate	2.89%
Fixed Rate Debt | Unsecured Debt | 3.50 Medium-Term Note due July 2027
Secured Debt
Stated interest rate	3.50%		3.50%
Portion of medium term note subject to interest rate swaps	$ 200,000
All-in weighted average interest rate	4.03%
Fixed Rate Debt | Unsecured Debt | 4.40% Medium-Term Notes due January 2029
Secured Debt
Principal outstanding					$ 300,000
Stated interest rate	4.40%		4.40%
Portion of medium term note subject to interest rate swaps	$ 150,000
All-in weighted average interest rate	4.27%
Fixed Rate Debt | Unsecured Debt | 3.20% Medium-Term Notes due January 2030
Secured Debt
Stated interest rate	3.20%		3.20%
All-in weighted average interest rate						3.32%
Fixed Rate Debt | Unsecured Debt | 3.00% Medium-Term Notes due August 2031
Secured Debt
Stated interest rate	3.00%		3.00%
Unamortized net premium	$ 11,200
Fixed Rate Debt | Unsecured Debt | 2.10% Medium Term Note Due August 2032
Secured Debt
Stated interest rate	2.10%
Fixed Rate Debt | Unsecured Debt | 2.10% Medium-Term Note due June 2033
Secured Debt
Stated interest rate	2.10%		2.10%
Fixed Rate Debt | Unsecured Debt | 3.10% senior unsecured notes due 2034
Secured Debt
All-in weighted average interest rate	3.13%
Fixed Rate Debt | Unsecured Debt | 1.90% Medium-Term Notes due March 2033
Secured Debt
Stated interest rate	1.90%		1.90%
Fixed Rate Debt | Secured Debt
Secured Debt
Long-term Debt	$ 1,006,482
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable
Secured Debt
Long-term Debt	1,029,168		$ 1,030,440
Fixed Rate Debt | Debt Assumed As Part of Acquisition | Mortgages Notes Payable
Secured Debt
Amortization of debt discount (Premium)	1,100	$ 700
Variable Rate Debt | Secured Debt
Secured Debt
Long-term Debt	27,000
Variable Rate Debt | Tax-exempt notes payable | Mortgages Notes Payable
Secured Debt
Principal outstanding	$ 27,000
Variable Rate Debt | Tax-exempt secured notes payable | Mortgages Notes Payable
Secured Debt
Notes payable maximum interest rates range	0.87%

INCOME (LOSS) PER SHARE (Detail

INCOME (LOSS) PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Jul. 31, 2021
Antidilutive securities
Net income/(loss)	$ 14,603	$ 3,274
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(879)	(154)
Net (income)/loss attributable to noncontrolling interests	(19)	(16)
Net income/(loss) attributable to UDR, Inc.	13,705	3,104
Distributions to preferred stockholders - Series E (Convertible)	(1,092)	(1,056)
Net income/(loss) attributable to common stockholders	$ 12,613	$ 2,048
Denominator for income/(loss) per share:
Weighted average common shares outstanding	318,293,000	296,800,000
Non-vested restricted stock awards	(284,000)	(263,000)
Denominator for basic income/(loss) per share	318,009,000	296,537,000
Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, unvested restricted stock and shares issuable upon settlement of forward sales agreements	1,671,000	489,000
Denominator for diluted income/(loss) per share	319,680,000	297,026,000
Income/(loss) per weighted average common share - basic	$ 0.04	$ 0.01
Income/(loss) per weighted average common share - diluted	$ 0.04	$ 0.01
Number of shares authorized	450,000,000		450,000,000
Aggregate net proceeds	$ (99)
Aggregate net proceeds from sales, after deducting related costs	$ (99)
OP/DownREIT Units
Antidilutive securities
Antidilutive securities	21,534,000	22,398,000
Convertible Preferred Stock
Antidilutive securities
Antidilutive securities	2,918,000	2,918,000
Unvested LTIP Units and unvested restricted stock
Antidilutive securities
Antidilutive securities	1,671,000	489,000
ATM
Denominator for income/(loss) per share:
Number of shares authorized				20,000,000
Forward price	$ 53.72
Shares of common stock available for future issuance	18,400,000
Shares non-settled	4,400,000
Forward Sales Agreement
Denominator for income/(loss) per share:
Aggregate number of shares	4,400,000
Forward price	$ 57.565
Shares of common stock available for future issuance	7,000,000

NONCONTROLLING INTERESTS (Detai

NONCONTROLLING INTERESTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Redeemable noncontrolling interests in the Operating Partnership
Minimum holding period prior to redemption (in years)	1 year
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, at beginning of year	$ 1,299,442
Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(43,747)	$ 131,700
Conversion of OP Units/DownREIT Units to Common Stock or Cash	(23,944)
Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	879	154
Distributions to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(8,383)
Redeemable Long-Term Incentive Plan Units	37,383
Allocation of other comprehensive income/(loss)	514
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, at end of year	1,262,144
Net income/(loss) attributable to noncontrolling interests		8
Maximum
Redeemable noncontrolling interests in the Operating Partnership
Net income/(loss) attributable to noncontrolling interests	$ (100)	$ (100)

FAIR VALUE OF DERIVATIVES AND_3

FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Fair Value
Notes receivable, net	$ 26,577	$ 26,860
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	1,262,144	$ 1,299,442
Transfers between levels of fair value hierarchy	$ 0
Equity Securities
Debt instruments - fair value
Percentage Of illiquidity discount	15.00%	15.00%
Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	$ 26,577	$ 26,860
Total assets	44,401	33,369
Debt instruments - fair value
Total liabilities	5,509,138	5,443,393
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	1,262,144	1,299,442
Carrying (Reported) Amount, Fair Value Disclosure | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	10,488	3,279
Carrying (Reported) Amount, Fair Value Disclosure | Equity Securities | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	7,336	3,230
Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	26,818	27,372
Total assets	44,642	33,881
Debt instruments - fair value
Total liabilities	5,199,869	5,508,491
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	1,262,144	1,299,442
Estimate of Fair Value, Fair Value Disclosure | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	10,488	3,279
Estimate of Fair Value, Fair Value Disclosure | Equity Securities | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	7,336	3,230
Estimate of Fair Value, Fair Value Disclosure | Level 1 | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	7,336
Estimate of Fair Value, Fair Value Disclosure | Level 1 | Equity Securities | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities	7,336
Estimate of Fair Value, Fair Value Disclosure | Level 2 | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	10,488	3,279
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	1,262,144	1,299,442
Estimate of Fair Value, Fair Value Disclosure | Level 2 | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	10,488	3,279
Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	26,818	27,372
Total assets	26,818	30,602
Debt instruments - fair value
Total liabilities	5,199,869	5,508,491
Estimate of Fair Value, Fair Value Disclosure | Level 3 | Equity Securities | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Equity securities		3,230
Unsecured Debt | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,132,574	4,133,083
Unsecured Debt | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	3,876,882	4,199,363
Unsecured Debt | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	3,876,882	4,199,363
Unsecured Debt | Working capital credit facility | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	37,194	29,546
Unsecured Debt | Working capital credit facility | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	37,194	29,546
Unsecured Debt | Working capital credit facility | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	37,194	29,546
Unsecured Debt | Commercial Paper | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	280,000	220,000
Unsecured Debt | Commercial Paper | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	280,000	220,000
Unsecured Debt | Commercial Paper | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	280,000	220,000
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,032,370	1,033,764
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	978,793	1,032,582
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	978,793	1,032,582
Variable Rate Debt | Secured Debt | Tax-exempt secured notes payable | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	27,000	27,000
Variable Rate Debt | Secured Debt | Tax-exempt secured notes payable | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	27,000	27,000
Variable Rate Debt | Secured Debt | Tax-exempt secured notes payable | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	$ 27,000	$ 27,000

DERIVATIVES AND HEDGING ACTIV_3

DERIVATIVES AND HEDGING ACTIVITY - Interest Rate Derivatives (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)instrument
Derivatives
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	$ 900
Designated as Hedging Instrument | Interest rate swap and caps
Derivatives
Number of Interest Rate Derivatives Held | instrument	4
Notional	$ 334,880
Designated as Hedging Instrument | Interest rate swaps | Derivative Instrument That Becomes Effective In July 2022
Derivatives
Notional	$ 175,000
Number of additional interest rate derivative instruments entered | instrument	2
Notional value of contracts maturing	$ 315,000
Not Designated as Hedging Instrument
Derivatives
Notional	$ 0

DERIVATIVES AND HEDGING ACTIV_4

DERIVATIVES AND HEDGING ACTIVITY - Undesignated Interest Rate Derivatives (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Interest rate contracts | Other assets | Designated as Hedging Instrument
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheets
Derivative Asset Designated as Hedging Instrument, Fair Value	$ 10,488	$ 3,279

DERIVATIVES AND HEDGING ACTIV_5

DERIVATIVES AND HEDGING ACTIVITY - Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Effect of derivative instruments on the Consolidated Statements of Operations
Unrealized holding gain/(loss)	$ 7,193	$ 127
Interest rate contracts | Interest expense | Cash Flow Hedging
Effect of derivative instruments on the Consolidated Statements of Operations
Unrealized holding gain/(loss)	7,193	127
Gain/(Loss) reclassified from Accumulated OCI in Interest Expense	$ (387)	$ (446)

DERIVATIVES AND HEDGING ACTIV_6

DERIVATIVES AND HEDGING ACTIVITY - Effectiveness (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Derivatives and hedging activity
Total amount of Interest expense presented on the Consolidated Statements of Operations	$ 35,916	$ 78,156

DERIVATIVES AND HEDGING ACTIV_7

DERIVATIVES AND HEDGING ACTIVITY - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Offsetting derivative assets
Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)	$ 10,488	$ 3,279
Net Amount	$ 10,488	$ 3,279

STOCK BASED COMPENSATION (Detai

STOCK BASED COMPENSATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
General and administrative expense
Stock based compensation
Stock based compensation expense	$ 6.4	$ 4.9

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Apr. 27, 2022USD ($)	Mar. 31, 2022USD ($)community	Feb. 28, 2022USD ($)
Real estate properties
Number of communities owned (in communities) | community		160
Costs Incurred to Date		$ 607,461
UDR's Remaining Commitment		293,379
Real estate technology investments RETV I
Real estate properties
Costs Incurred to Date		51,912
UDR's Remaining Commitment		5,220
Real estate technology investments RETV II
Real estate properties
Costs Incurred to Date		7,818
UDR's Remaining Commitment		10,800
Real estate technology investments RETV Strategic Fund
Real estate properties
Costs Incurred to Date		7,517
UDR's Remaining Commitment		17,500
Climate Technology Fund
Real estate properties
Costs Incurred to Date		5,721
UDR's Remaining Commitment		4,279
Contractual commitment		$ 10,000
ESG Technology Fund
Real estate properties
Contractual commitment	$ 10,000
Land To-be-Developed Fort Lauderdale, Florida
Real estate properties
Contractual commitment			$ 16,000
Wholly owned - under development
Real estate properties
Number of communities owned (in communities) | community		7
Costs Incurred to Date		$ 458,111
UDR's Remaining Commitment		$ 230,889
Preferred Equity Investments
Real estate properties
Number of communities owned (in communities) | community		3
Costs Incurred to Date		$ 76,382
UDR's Remaining Commitment		$ 24,691

REPORTABLE SEGMENTS (Details)

REPORTABLE SEGMENTS (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)segmenthome	Mar. 31, 2021USD ($)home	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Segments
Same store communities | home	47,443	47,443
Reportable Segments
Number of reportable segments | segment	2
Condition for Community considered to have stabilized occupancy	90%
Time to maintain percent occupancy to be considered a community	3 months
Practical expedient, single lease component	true
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Rental income	$ 356,181	$ 299,826
Reconciling items:
Joint venture management and other fees	$ 1,085	$ 1,615
Type of revenue	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
Property management	$ (11,576)	$ (8,995)
Other operating expenses	(4,712)	(4,435)
Real estate depreciation and amortization	(163,622)	(144,088)
General and administrative	(14,908)	(12,736)
Casualty-related (charges)/recoveries, net	765	(5,577)
Other depreciation and amortization	(3,075)	(2,601)
Gain/(loss) on sale of real estate owned		50,829
Income/(loss) from unconsolidated entities	5,412	4,922
Interest expense	(35,916)	(78,156)
Interest income and other income/(expense), net	(2,440)	2,057
Tax (provision)/benefit, net	(343)	(619)
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(879)	(154)
Net (income)/loss attributable to noncontrolling interests	(19)	(16)
Net income/(loss) attributable to UDR, Inc.	13,705	3,104
Reportable apartment home segment assets:
Total segment assets	14,833,055		$ 14,740,803
Accumulated depreciation	(5,289,853)		(5,137,096)
Total real estate owned, net of accumulated depreciation	9,543,202		9,603,707
Reconciling items:
Cash and cash equivalents	895	1,172	967	$ 1,409
Restricted cash	26,032	33,428	27,451	$ 22,762
Notes receivable, net	26,577		26,860
Investment in and advances to unconsolidated joint ventures, net	669,343		702,461
Operating lease right-of-use assets	196,578		197,463
Other assets	222,337		216,311
Total consolidated assets	10,684,964		10,775,220
Same Store Communities Western Region
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	111,649	99,766
Other revenue	2,960	2,710
Rental income	114,609	102,476
Reportable apartment home segment NOI	85,636	74,593
Reportable apartment home segment assets:
Total segment assets	4,301,470		4,288,116
Same Store Communities Mid-Atlantic Region
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	65,820	61,847
Other revenue	2,363	1,909
Rental income	68,183	63,756
Reportable apartment home segment NOI	46,983	43,620
Reportable apartment home segment assets:
Total segment assets	2,863,633		2,856,144
Same Store Communities Northeast Region
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	64,412	58,287
Other revenue	1,257	1,103
Rental income	65,669	59,390
Reportable apartment home segment NOI	42,083	36,328
Reportable apartment home segment assets:
Total segment assets	3,342,355		3,338,497
Same Store Communities Southeastern Region
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	44,322	38,767
Other revenue	1,792	1,635
Rental income	46,114	40,402
Reportable apartment home segment NOI	31,461	26,645
Reportable apartment home segment assets:
Total segment assets	1,212,612		1,208,183
Same Store Communities Southwestern Region
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	26,047	23,211
Other revenue	892	875
Rental income	26,939	24,086
Reportable apartment home segment NOI	17,339	14,835
Reportable apartment home segment assets:
Total segment assets	902,350		900,931
Non-Mature communities/Other
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	33,457	9,569
Other revenue	1,210	147
Rental income	34,667	9,716
Reportable apartment home segment NOI	20,431	5,037
Reportable apartment home segment assets:
Total segment assets	2,210,635		$ 2,148,932
Total Communities
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	345,707	291,447
Other revenue	10,474	8,379
Rental income	356,181	299,826
Reportable apartment home segment NOI	$ 243,933	$ 201,058
Taxable REIT Subsidiaries
Reportable Segments
Management fee (as a percent)	3.25%