UDR (UDR) 10-Q 1 May 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	Apr. 29, 2024
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
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		329,306,648
Entity Central Index Key	0000074208
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Real estate owned:
Real estate held for investment	$ 15,865,033	$ 15,757,456
Less: accumulated depreciation	(6,407,092)	(6,242,686)
Real estate held for investment, net	9,457,941	9,514,770
Real estate under development (net of accumulated depreciation of $19 and $184, respectively)	126,144	160,220
Real estate held for disposition (net of accumulated depreciation of $0 and $24,960, respectively)		81,039
Total real estate owned, net of accumulated depreciation	9,584,085	9,756,029
Cash and cash equivalents	2,116	2,922
Restricted cash	29,850	31,944
Notes receivable, net	235,382	228,825
Investment in and advances to unconsolidated joint ventures, net	954,301	952,934
Operating lease right-of-use assets	189,729	190,619
Other assets	195,025	209,969
Total assets	11,190,488	11,373,242
Liabilities:
Secured debt, net	1,236,779	1,277,713
Unsecured debt, net	4,525,549	4,520,996
Operating lease liabilities	184,961	185,836
Real estate taxes payable	37,917	47,107
Accrued interest payable	27,255	47,710
Security deposits and prepaid rent	50,187	50,528
Distributions payable	151,512	149,600
Accounts payable, accrued expenses, and other liabilities	119,739	141,311
Total liabilities	6,333,899	6,420,801
Commitments and contingencies (Note 13)
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	937,311	961,087
Equity:
Common stock, $0.01 par value; 450,000,000 shares authorized at March 31, 2024 and December 31, 2023: 329,327,553 and 329,014,512 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively	3,293	3,290
Additional paid-in capital	7,500,170	7,493,217
Distributions in excess of net income	(3,638,370)	(3,554,892)
Accumulated other comprehensive income/(loss), net	9,235	4,914
Total stockholders' equity	3,918,943	3,991,144
Noncontrolling interests	335	210
Total equity	3,919,278	3,991,354
Total liabilities and equity	11,190,488	11,373,242
8.00% Series E Cumulative Convertible Preferred Stock
Equity:
Preferred stock, no par value; 50,000,000 shares authorized at March 31, 2024 and December 31, 2023:	44,614	44,614
Series F
Equity:
Preferred stock, no par value; 50,000,000 shares authorized at March 31, 2024 and December 31, 2023:	$ 1	$ 1

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Real estate owned:
Real estate under development accumulated depreciation	$ 19	$ 184
Real estate held for disposition accumulated depreciation	$ 0	$ 24,960
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	329,327,553	329,014,512
Common stock, shares outstanding	329,327,553	329,014,512
8.00% Series E Cumulative Convertible Preferred Stock
Equity:
Preferred stock, dividend rate percentage	8%	8%
Preferred stock, shares issued	2,686,308	2,686,308
Preferred stock, shares outstanding	2,686,308	2,686,308
Series F
Equity:
Preferred stock, shares issued	11,785,976	11,867,730
Preferred stock, shares outstanding	11,785,976	11,867,730

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
REVENUES:
Rental income	$ 411,669	$ 398,307
Joint venture management and other fees	$ 1,965	$ 1,242
Type of revenue	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
Total revenues	$ 413,634	$ 399,549
OPERATING EXPENSES:
Property operating and maintenance	73,478	64,834
Real estate taxes and insurance	58,795	57,970
Property management	13,379	12,945
Other operating expenses	6,828	3,032
Real estate depreciation and amortization	169,858	169,300
General and administrative	17,810	17,480
Casualty-related charges/(recoveries), net	6,278	4,156
Other depreciation and amortization	4,316	3,649
Total operating expenses	350,742	333,366
Gain/(loss) on sale of real estate owned	16,867	1
Operating income	79,759	66,184
Income/(loss) from unconsolidated entities	9,085	9,707
Interest expense	(48,062)	(43,742)
Interest income and other income/(expense), net	5,865	1,010
Income/(loss) before income taxes	46,647	33,159
Tax (provision)/benefit, net	(337)	(234)
Net income/(loss)	46,310	32,925
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(3,149)	(1,953)
Net (income)/loss attributable to noncontrolling interests	(12)	(8)
Net income/(loss) attributable to UDR, Inc.	43,149	30,964
Distributions to preferred stockholders - Series E (Convertible)	(1,231)	(1,183)
Net income/(loss) attributable to common stockholders	$ 41,918	$ 29,781
Income/(loss) per weighted average common share - basic	$ 0.13	$ 0.09
Income/(loss) per weighted average common share - diluted	$ 0.13	$ 0.09
Weighted average number of common shares outstanding - basic	328,823	328,789
Weighted average number of common shares outstanding - diluted	328,954	329,421

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS)
Net income/(loss)	$ 46,310	$ 32,925
Other comprehensive income/(loss), including portion attributable to noncontrolling interests:
Unrealized holding gain/(loss)	6,664	(273)
(Gain)/loss reclassified into earnings from other comprehensive income/(loss)	(1,995)	(1,369)
Other comprehensive income/(loss), including portion attributable to noncontrolling interests	4,669	(1,642)
Comprehensive income/(loss)	50,979	31,283
Comprehensive (income)/loss attributable to noncontrolling interests	(3,509)	(1,840)
Comprehensive income/(loss) attributable to UDR, Inc.	$ 47,470	$ 29,443

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	Accumulated Other Comprehensive Income/(Loss)	Noncontrolling Interest	Total
Beginning Balance at Dec. 31, 2022	$ 44,615	$ 3,290	$ 7,493,423	$ (3,451,587)	$ 8,344	$ 210	$ 4,098,295
Consolidated Statements of Changes in Equity
Net income/(loss) attributable to UDR, Inc.				30,964			30,964
Other comprehensive income/(loss)					(1,521)		(1,521)
Issuance/(forfeiture) of common and restricted shares, net		2	695				697
Issuance of common shares through public offering, net			(462)				(462)
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership			386				386
Common stock distributions declared				(138,318)			(138,318)
Preferred stock distributions declared-Series E				(1,183)			(1,183)
Adjustment to reflect redemption value of redeemable noncontrolling interests				(67,749)			(67,749)
Ending Balance at Mar. 31, 2023	44,615	3,292	7,494,042	(3,627,873)	6,823	210	3,921,109
Beginning Balance at Dec. 31, 2023	44,615	3,290	7,493,217	(3,554,892)	4,914	210	3,991,354
Consolidated Statements of Changes in Equity
Net income/(loss) attributable to UDR, Inc.				43,149			43,149
Other comprehensive income/(loss)					4,321		4,321
Issuance/(forfeiture) of common and restricted shares, net		1	85				86
Issuance of common shares through public offering, net			(418)				(418)
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership		2	7,286				7,288
Contribution of noncontrolling interests in consolidated real estate						125	125
Common stock distributions declared				(140,025)			(140,025)
Preferred stock distributions declared-Series E				(1,231)			(1,231)
Adjustment to reflect redemption value of redeemable noncontrolling interests				14,629			14,629
Ending Balance at Mar. 31, 2024	$ 44,615	$ 3,293	$ 7,500,170	$ (3,638,370)	$ 9,235	$ 335	$ 3,919,278

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY
Common stock distributions declared per share	$ 0.425	$ 0.42
Preferred stock distributions in arrears	$ 0.4602	$ 0.4548

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities
Net income/(loss)	$ 46,310	$ 32,925
Adjustments to reconcile net income/(loss) to net cash provided by/(used in) operating activities:
Depreciation and amortization	174,174	172,949
(Gain)/loss on sale of real estate owned	(16,867)	(1)
(Income)/loss from unconsolidated entities	(9,085)	(9,707)
Return on investment in unconsolidated joint ventures and partnerships	4,596	4,317
Amortization of share-based compensation	7,258	8,246
Other	10,377	7,690
Changes in operating assets and liabilities:
(Increase)/decrease in operating assets	1,447	(7,119)
Increase/(decrease) in operating liabilities	(50,611)	(41,285)
Net cash provided by/(used in) operating activities	167,599	168,015
Investing Activities
Proceeds from sales of real estate investments, net	98,650
Development of real estate assets	(30,595)	(42,498)
Capital expenditures and other major improvements - real estate assets	(52,563)	(54,353)
Capital expenditures - non-real estate assets	(4,583)	(4,532)
Investment in unconsolidated joint ventures and partnerships	(1,105)	(1,821)
Distributions received from unconsolidated joint ventures and partnerships	4,289	3,108
Proceeds from sale of equity securities	4,624
Purchase deposits on pending acquisitions		(743)
Repayment/(issuance) of notes receivable, net	(270)	(16,501)
Net cash provided by/(used in) investing activities	18,447	(117,340)
Financing Activities
Payments on secured debt	(40,749)	(292)
Net proceeds/(repayment) of commercial paper	(18,075)	105,000
Net proceeds/(repayment) of revolving bank debt	22,467	(14,244)
Distributions paid to redeemable noncontrolling interests	(10,452)	(8,178)
Distributions paid to preferred stockholders	(1,210)	(1,097)
Distributions paid to common stockholders	(138,247)	(125,083)
Other	(2,680)	(7,765)
Net cash provided by/(used in) financing activities	(188,946)	(51,659)
Net increase/(decrease) in cash, cash equivalents, and restricted cash	(2,900)	(984)
Cash, cash equivalents, and restricted cash, beginning of year	34,866	30,194
Cash, cash equivalents, and restricted cash, end of period	31,966	29,210
Supplemental Information:
Interest paid during the period, net of amounts capitalized	69,197	64,707
Operating cash flows from operating leases	3,126	3,126
Cash paid/(refunds received) for income taxes	(51)	206
Non-cash transactions:
Redeemable long-term and short-term incentive plan units		6,989
Development costs and capital expenditures incurred, but not yet paid	34,728	35,524
Conversion of Operating Partnership and DownREIT Partnership noncontrolling interests to common stock (190,278 shares and 9,957 shares, respectively)	7,288	386
Distribution of equity securities from unconsolidated real estate technology investments		7,749
Dividends declared, but not yet paid	$ 151,512	$ 148,409

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS - CASH RECONCILIATION - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
The following reconciles cash, cash equivalents, and restricted cash to amounts as shown above:
Cash and cash equivalents	$ 2,116	$ 2,922	$ 1,172	$ 1,193
Restricted cash	29,850	31,944	28,038	29,001
Total cash, cash equivalents, and restricted cash as shown above	$ 31,966	$ 34,866	$ 29,210	$ 30,194

CONSOLIDATED STATEMENTS OF CA_3

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Non-cash transactions:
Conversion of OP Units into common shares (in shares)	190,278	9,957

BASIS OF PRESENTATION

BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2024
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, 2024, our consolidated apartment portfolio consisted of 168 communities with a total of 55,386 apartment homes located in 21 markets. In addition, the Company has an ownership interest in 10,045 completed or to-be-completed apartment homes through unconsolidated joint ventures or partnerships, including 5,618 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 , Joint Ventures and Partnerships 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, 2024, there were 190.0 million units in the Operating Partnership (“OP Units”) outstanding, of which 176.5 million OP Units (including 0.1 million of general partnership units), or 92.9%, were owned by UDR and 13.5 million OP Units, or 7.1%, were owned by outside limited partners. As of March 31, 2024, there were 32.4 million units in the DownREIT Partnership (“DownREIT Units”) outstanding, of which 21.5 million, or 66.4%, were owned by UDR and its subsidiaries and 10.9 million, or 33.6%, 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, 2024, and results of operations for the three months ended March 31, 2024 and 2023, 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, 2023 appearing in UDR’s Annual Report on Form 10-K, filed with the SEC on February 20, 2024. 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 2, Significant Accounting Policies

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2024
SIGNIFICANT ACCOUNTING POLICIES
SIGNIFICANT ACCOUNTING POLICIES	2. SIGNIFICANT ACCOUNTING POLICIES Recent Accounting Pronouncements In March 2024, the SEC issued final rules on the enhancement and standardization of climate-related disclosures. The rules require disclosure of, among other things: material climate-related risks; activities to mitigate or adapt to such risks; governance and management of such risks; and material greenhouse gas emissions from operations owned or controlled (Scope 1) and/or indirect emissions from purchased energy consumed in operations (Scope 2). Additionally, the rules require disclosure in the notes to the financial statements of the effects of severe weather events and other natural conditions, subject to certain materiality thresholds. The rules will become effective for the Company on a phased-in timeline starting in the year ended December 31, 2025. While the SEC has voluntarily stayed the rules, the Company is currently evaluating the effect the rules will have on its financial statement disclosures. ​ In December 2023, the Financial Accounting Standards Board (“FASB”) issued 2023-09, Income Taxes (Topic 740) – Improvements to Income Tax Disclosures , ​ In November 2023, , Segment Reporting (Topic 280) – Improvements to Reportable Segments Disclosures ​ 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 been transferred by the Company, 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 Accounting Standards Codification (“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 (a) ​ March 31, March 31, December 31, ​ ​ 2024 ​ 2024 ​ 2023 Notes due October 2024 (b) ​ 10.50 % $ 100,859 ​ $ 98,271 Note due December 2024 (c) ​ 12.00 % ​ 38,411 ​ ​ 37,022 Note due December 2026 (d) ​ 11.00 % ​ 66,317 ​ ​ 64,608 Note due December 2026 (e) ​ 11.00 % ​ 26,872 ​ ​ 26,164 Notes due June 2027 (f) ​ 18.00 % ​ 3,907 ​ ​ 3,737 Notes receivable ​ ​ ​ ​ 236,366 ​ ​ 229,802 Allowance for credit losses ​ ​ ​ ​ (984) ​ ​ (977) Total notes receivable, net ​ $ 235,382 ​ $ 228,825 (a) Outstanding note amounts include any accrued and unpaid interest, as applicable. (b) The Company has two loans (the “Notes”) with a joint venture that owns a 478 apartment home operating community located in Philadelphia, Pennsylvania with an aggregate commitment of $93.5 million (exclusive of accrued interest), all of which has been funded. The Notes are subordinate to the senior construction loan, but senior to the equity in the borrower. Currently, the Notes have a scheduled maturity date in October 2024, with two remaining one-year extension options. In April 2024, the joint venture refinanced the senior construction loan with a new loan that matures in April 2026, with a one year extension option subject to certain conditions. (c) The Company has a secured note with an unaffiliated third party with an aggregate commitment of $32.5 million, of which $31.8 million was funded as of March 31, 2024. Interest payments are due monthly, with the exception of payments from June 2022 to December 2024, which are accrued and added to the principal balance and will be due at maturity of the note. 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) December 2024. (d) The Company has a secured mezzanine loan with a third party developer of a 482 apartment home community located in Riverside, California, which is expected to be completed in 2025, with an aggregate commitment of $59.7 million (exclusive of accrued interest), all of which has been funded. Interest payments accrue for 36 months and are due monthly after the loan has been outstanding for 36 months . The secured mezzanine loan has a scheduled maturity date in December 2026, with two one-year extension options. (e) The Company has a secured mezzanine loan with a third party developer of a 237 apartment home community located in Menifee, California, which is expected to be completed in 2025, with an aggregate commitment of $24.4 million (exclusive of accrued interest), all of which has been funded. Interest payments accrue for 36 months and are due monthly after the loan has been outstanding for 36 months . The secured mezzanine loan has a scheduled maturity date in December 2026, with two one-year extension options. (f) The Company and a syndicate of lenders previously entered into a $16.0 million secured credit facility with an unaffiliated third party. In 2023, the secured credit facility was amended to provide a new term loan in the amount of $19.0 million, and the Company’s commitment was increased from $1.5 million to $3.0 million (exclusive of accrued interest) , all of which has been funded. Interest payments accrue and are due at maturity of the facility. The facility is secured by substantially all of the borrower’s assets and matures at the earliest of the following: (a) acceleration in the event of default; or (b) June 2027. The Company recognized $6.3 million and $1.6 million of interest income for the notes receivable described above during the three months ended March 31, 2024 and 2023, 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, 2024 and 2023, 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, 2024 and December 31, 2023, 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, 2024. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2020 through 2022 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 ​ Lease Receivables ​ During the three months ended March 31, 2024 and 2023, the Company performed an analysis in accordance with the ASC 842, Leases, guidance to assess the collectibility of its operating lease receivables. 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 collection of lease payments is 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 of March 31, 2024, the Company’s multifamily tenant lease receivables balance, net of its reserve, was approximately $7.7 million, including its share from unconsolidated joint ventures. The Company’s retail tenant lease receivables balance (exclusive of straight-line rent receivables), net of its reserve, was approximately $0.4 million, including its share from unconsolidated joint ventures, as of March 31, 2024.

REAL ESTATE OWNED

REAL ESTATE OWNED	3 Months Ended
	Mar. 31, 2024
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, 2024, the Company owned and consolidated 168 communities in 13 states plus the District of Columbia totaling 55,386 apartment homes. The following table summarizes the carrying amounts for our real estate owned (at cost) as of March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Land ​ $ 2,559,184 ​ $ 2,549,716 Depreciable property — held and used: ​ ​ ​ ​ Land improvements ​ 257,791 ​ 255,706 Building, improvements, and furniture, fixtures and equipment ​ 12,998,045 ​ 12,902,021 Real estate intangible assets ​ ​ 50,013 ​ ​ 50,013 Under development: ​ ​ Land and land improvements ​ 6,611 ​ 16,576 Building, improvements, and furniture, fixtures and equipment ​ 119,552 ​ 143,828 Real estate held for disposition: ​ ​ Land and land improvements ​ — ​ 13,734 Building, improvements, and furniture, fixtures and equipment ​ — ​ 92,265 Real estate owned ​ 15,991,196 ​ 16,023,859 Accumulated depreciation (a) ​ (6,407,111) ​ (6,267,830) Real estate owned, net ​ $ 9,584,085 ​ $ 9,756,029 (a) Accumulated depreciation is inclusive of $18.2 million and $17.2 million of accumulated amortization related to real estate intangible assets as of March 31, 2024 and December 31, 2023, respectively. ​ Acquisitions In January 2024, the Company acquired its joint venture partner’s common Joint Ventures and Partnerships . ​ Dispositions ​ In February 2024, the Company sold an operating community located in Arlington, Virginia with a total of 214 apartment homes for gross proceeds of $100.0 million, resulting in a gain of approximately $16.9 million. This operating community was classified as held for disposition as of December 31, 2023. Other Activity Total real estate owned, net of accumulated depreciation 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, 2024 and 2023. 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 some of which 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, 2024
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, 2024
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. Consolidated joint venture ​ The Company previously held a preferred equity investment in a joint venture that owned a 173 apartment home community located in Oakland, California. In 2023, the joint venture was deemed to be a VIE and the Company concluded that it was the primary beneficiary of the VIE, and therefore began consolidating the joint venture. In January 2024, the Company took title to the developer’s equity interest in the joint venture resulting in it being a wholly-owned community. (See Note 3, Real Estate Owned . ​ Unconsolidated 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, 2024 and December 31, 2023 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Number of ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ Apartment ​ UDR's Weighted Average ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ Communities ​ Homes ​ Ownership Interest ​ ​ Investment at ​ Three Months Ended ​ March 31, March 31, ​ March 31, ​ December 31, March 31, December 31, ​ March 31, Joint Ventures 2024 2024 ​ 2024 2023 2024 2023 ​ 2024 2023 Operating: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ UDR/MetLife (a) ​ 13 ​ 2,837 ​ 50.2 % ​ 50.2 % ​ $ 219,387 ​ $ 225,195 ​ $ (1,846) ​ $ (1,350) UDR/LaSalle ​ 5 ​ 1,590 ​ 51.0 % ​ 51.0 % ​ ​ 281,314 ​ ​ 286,723 ​ ​ (2,878) ​ ​ — Total Joint Ventures ​ 18 4,427 ​ ​ ​ ​ $ 500,701 ​ $ 511,918 ​ $ (4,724) ​ $ (1,350) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Apartment ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ Communities ​ Homes ​ Weighted ​ ​ ​ ​ ​ ​ ​ Investment at ​ Three Months Ended Developer Capital Program March 31, ​ March 31, ​ Average ​ Years To ​ UDR March 31, December 31, ​ March 31, and Real Estate Technology Investments (b) 2024 ​ 2024 ​ Rate ​ Maturity ​ Commitment (c) 2024 2023 2024 2023 Preferred equity investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ 21 ​ 4,545 ​ 9.3 % ​ 3.1 ​ $ 252,889 ​ $ 308,820 ​ $ 304,699 ​ $ 5,920 ​ $ 6,643 Development ​ 2 ​ 1,073 ​ 10.7 % ​ 3.3 ​ ​ 68,207 ​ ​ 85,315 ​ ​ 83,072 ​ ​ 2,243 ​ ​ 1,992 Total Preferred Equity Investments ​ 23 ​ 5,618 ​ 9.6 % ​ 3.1 ​ $ 321,096 ​ ​ 394,135 ​ ​ 387,771 ​ ​ 8,163 ​ ​ 8,635 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real estate technology and sustainability investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real estate technology and sustainability investments ​ N/A ​ N/A ​ N/A ​ ​ N/A ​ $ 86,000 ​ ​ 50,528 ​ ​ 44,382 ​ ​ 5,646 ​ ​ 935 Total Preferred Equity Investments and Real Estate Technology and Sustainability Investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 444,663 ​ ​ 432,153 ​ ​ 13,809 ​ ​ 9,570 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sold joint ventures and other investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ — ​ ​ — ​ ​ — ​ ​ 1,487 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total investment in and advances to unconsolidated joint ventures, net (a) ​ ​ ​ ​ $ 945,364 ​ $ 944,071 ​ $ 9,085 $ 9,707 (a) As of March 31, 2024 and December 31, 2023, the Company’s negative investment in one UDR/MetLife community of $8.9 million and $8.9 million, respectively, is recorded in Accounts payable, accrued expenses, and other liabilities on the Consolidated Balance Sheets. (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. At March 31, 2024, our preferred equity investment portfolio consisted of 23 communities located in various markets, consisting of 5,618 completed or under development homes. In addition, the Company’s preferred equity investments include four investments that receive a variable percentage of the value created from the project upon a capital or liquidating event. During the three months ended March 31, 2024, the Company did not enter into or fund any new preferred equity investments and no preferred equity investments were redeemed. (c) Represents UDR’s maximum funding commitment only and therefore excludes other activity such as income from investments. ​ As of March 31, 2024 and December 31, 2023, the Company had deferred fees of $7.5 million and $7.6 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 $2.0 million and $1.2 million for the three months ended March 31, 2024 and 2023, 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, 2024 and December 31, 2023 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2024 2023 Total real estate, net $ 3,180,973 $ 3,158,057 Investments, at fair value ​ ​ 304,826 ​ ​ 257,832 Cash and cash equivalents ​ 69,247 ​ 61,670 Other assets ​ ​ 135,491 ​ 146,976 Total assets $ 3,690,537 $ 3,624,535 ​ ​ ​ ​ ​ ​ ​ Third party debt, net ​ $ 2,027,146 ​ $ 2,012,816 Accounts payable and accrued liabilities ​ ​ 178,704 ​ ​ 171,502 Total liabilities ​ 2,205,850 ​ 2,184,318 Total equity $ 1,484,687 $ 1,440,217 ​ 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, 2024 and 2023 ( dollars in thousands : ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ 2024 2023 Total revenues $ 76,256 $ 60,675 Property operating expenses ​ 34,935 ​ 28,033 Real estate depreciation and amortization ​ 36,962 ​ 24,428 Operating income/(loss) ​ 4,359 ​ ​ 8,214 Interest expense ​ (24,537) ​ (23,951) Net unrealized/realized gain/(loss) on held investments ​ ​ 27,400 ​ ​ 9,789 Other income/(loss) ​ ​ (1,828) ​ ​ 2,322 Net income/(loss) $ 5,394 $ (3,626) ​

LEASES

LEASES	3 Months Ended
	Mar. 31, 2024
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, 2024 and 2023. As of March 31, 2024 and December 31, 2023, 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 41.8 years and 42.0 years at March 31, 2024 and December 31, 2023, respectively, and the weighted average discount rate was 5.0% at both March 31, 2024 and December 31, 2023. Future minimum lease payments and total operating lease liabilities from our ground leases as of March 31, 2024 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Ground Leases 2024 ​ $ 9,332 2025 ​ ​ 12,442 2026 ​ ​ 12,442 2027 ​ ​ 12,442 2028 ​ ​ 12,442 Thereafter ​ ​ 405,452 Total future minimum lease payments (undiscounted) ​ ​ 464,552 Difference between future undiscounted cash flows and discounted cash flows ​ ​ (279,591) Total operating lease liabilities (discounted) ​ $ 184,961 ​ 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, ​ ​ 2024 ​ 2023 Lease expense: ​ ​ ​ ​ ​ ​ Contractual lease expense ​ $ 3,350 ​ $ 3,292 Variable lease expense (a) ​ ​ 40 ​ ​ 28 Total operating lease expense (b)(c) ​ $ 3,390 ​ $ 3,320 (a) Variable lease expense includes adjustments such as changes in the consumer price index and payments based on a percentage of a community’s revenue. (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, 2024, Operating lease right-of-use assets and Operating lease liabilities amortized by $0.9 million and $0.9 million, respectively. For the three months ended March 31, 2023, 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 less than $0.1 million and less than $0.1 million of total operating lease expense during the three months ended March 31, 2024 and 2023, 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, 2024, our apartment home leases generally have initial terms of 12 months or less. As of March 31, 2024, 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 changes 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, 2024 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Retail and Commercial Leases 2024 ​ $ 19,844 2025 ​ ​ 24,675 2026 ​ ​ 21,896 2027 ​ ​ 18,252 2028 ​ ​ 15,464 Thereafter ​ ​ 59,571 Total future minimum lease payments (a) ​ $ 159,702 (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 $0.6 million and $0.7 million during the three months ended March 31, 2024 and 2023, respectively.

SECURED AND UNSECURED DEBT, NET

SECURED AND UNSECURED DEBT, NET	3 Months Ended
	Mar. 31, 2024
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, 2024 and December 31, 2023 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal Outstanding ​ As of March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Average ​ Number of ​ ​ March 31, ​ December 31, ​ Interest ​ Years to ​ Communities ​ 2024 2023 Rate Maturity Encumbered Secured Debt: ​ ​ ​ ​ ​ ​ ​ Fixed Rate Debt ​ ​ Mortgage notes payable (a) ​ $ 1,213,019 ​ $ 1,213,751 3.48 % 4.4 20 Deferred financing costs and other non-cash adjustments (b) ​ (3,196) ​ (3,009) Total fixed rate secured debt, net ​ 1,209,823 ​ 1,210,742 3.42 % 4.4 20 Variable Rate Debt ​ ​ Mortgage notes payable (c) ​ — ​ 40,017 — % — — Tax-exempt secured notes payable (d) ​ 27,000 ​ 27,000 4.05 % 8.0 1 Deferred financing costs ​ (44) ​ (46) Total variable rate secured debt, net ​ 26,956 ​ 66,971 4.08 % 8.0 1 Total Secured Debt, net ​ 1,236,779 ​ 1,277,713 3.44 % 4.5 21 Unsecured Debt: ​ ​ Variable Rate Debt ​ ​ Borrowings outstanding under unsecured credit facility due January 2026 (e) (n) ​ — ​ — — % 1.8 Borrowings outstanding under unsecured commercial paper program due April 2024 (f) (n) ​ ​ 390,000 ​ ​ 408,075 ​ 5.53 % 0.1 ​ ​ Borrowings outstanding under unsecured working capital credit facility due January 2025 ​ 27,059 ​ 4,593 6.21 % 0.8 Term Loan due January 2027 (e) (n) ​ 87,500 ​ — 6.24 % 2.8 Fixed Rate Debt ​ ​ Term Loan due January 2027 (e) (n) ​ ​ 262,500 ​ 350,000 2.68 % 2.8 ​ ​ 8.50% Debentures due September 2024 ​ 15,644 ​ 15,644 8.50 % 0.5 2.95% Medium-Term Notes due September 2026 (h) (n) ​ 300,000 ​ 300,000 2.89 % 2.4 3.50% Medium-Term Notes due July 2027 (net of discounts of $229 and $247, respectively) (i) (n) ​ ​ 299,771 ​ ​ 299,753 ​ 4.03 % 3.3 ​ ​ 3.50% Medium-Term Notes due January 2028 (net of discounts of $450 and $479, respectively) (n) ​ ​ 299,550 ​ ​ 299,521 ​ 3.50 % 3.8 ​ ​ 4.40% Medium-Term Notes due January 2029 (net of discounts of $3 and $3, respectively) (j) (n) ​ ​ 299,997 ​ ​ 299,997 ​ 4.27 % 4.8 ​ ​ 3.20% Medium-Term Notes due January 2030 (net of premiums of $7,951 and $8,294, respectively) (k) (n) ​ ​ 607,951 ​ ​ 608,294 ​ 3.32 % 5.8 ​ ​ 3.00% Medium-Term Notes due August 2031 (net of premiums of $8,810 and $9,109, respectively) (l) (n) ​ ​ 608,810 ​ ​ 609,109 ​ 3.01 % 7.4 ​ ​ 2.10% Medium-Term Notes due August 2032 (net of discounts of $294 and $303, respectively) (n) ​ ​ 399,706 ​ ​ 399,697 ​ 2.10 % 8.3 ​ ​ 1.90% Medium-Term Notes due March 2033 (net of discounts of $1,079 and $1,110, respectively) (n) ​ ​ 348,921 ​ ​ 348,890 ​ 1.90 % 9.0 ​ ​ 2.10% Medium-Term Notes due June 2033 (net of discounts of $916 and $941, respectively) (n) ​ ​ 299,084 ​ ​ 299,059 ​ 2.10 % 9.2 ​ ​ 3.10% Medium-Term Notes due November 2034 (net of discounts of $934 and $956, respectively) (m) (n) ​ ​ 299,066 ​ ​ 299,044 ​ 3.13 % 10.6 ​ ​ Other ​ 1 ​ 2 Deferred financing costs ​ (20,011) ​ (20,682) Total Unsecured Debt, net ​ 4,525,549 ​ 4,520,996 3.36 % 5.7 Total Debt, net ​ $ 5,762,328 ​ $ 5,798,709 3.38 % 5.4 ​ 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, 2024, secured debt encumbered approximately 13% of UDR’s total real estate owned based upon gross book value (approximately 87% 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) (e) Based on the Company’s current credit rating, the Revolving Credit Facility has an interest rate equal to Adjusted SOFR plus a margin of 75.5 basis points and a facility fee of 15 basis points, and the Term Loan has an interest rate equal to Adjusted SOFR plus a margin of 83.0 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 were reduced by two basis points upon the Company receiving certain green building certifications, which is reflected in the margins noted above. In August 2021 and March 2023, the Company entered into five interest rate swaps totaling $350.0 million of notional value, which became effective in July 2022 and in March 2023, to hedge against interest rate risk on all or a portion of the Term Loan debt until July 2025. $350.0 million of the Term Loan debt has a weighted average interest rate, inclusive of the impact of the interest rate swaps, of 3.36% from March 2023 until January 2024, $262.5 million of the Term Loan debt has a weighted average interest rate, inclusive of the impact of interest rate swaps, of 2.68% from January 2024 until July 2024, and $175.0 million of the Term Loan debt has a weighted average interest rate, inclusive of the impact of interest rate swaps, of 1.43% from July 2024 until July 2025 ​ 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, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 2023 ​ 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 ​ — ​ 2,055 ​ Maximum daily borrowings during the period ended ​ — ​ 250,000 ​ Weighted average interest rate during the period ended ​ — % 5.6 % Interest rate at end of the period ​ — % — % (1) Excludes $3.8 million and $2.3 million of letters of credit at March 31, 2024 and December 31, 2023, respectively . (f) The following is a summary of short-term bank borrowings under the unsecured commercial paper program at March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Total unsecured commercial paper program $ 700,000 ​ $ 700,000 ​ Borrowings outstanding at end of period ​ 390,000 ​ 408,075 ​ Weighted average daily borrowings during the period ended ​ 423,478 ​ 384,068 ​ Maximum daily borrowings during the period ended ​ 560,000 ​ 505,000 ​ Weighted average interest rate during the period ended ​ 5.6 % 5.4 % Interest rate at end of the period ​ 5.5 % 5.7 % ​ (g) The following is a summary of short-term bank borrowings under the Working Capital Credit Facility at March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Total working capital credit facility ​ $ 75,000 ​ $ 75,000 ​ Borrowings outstanding at end of period ​ 27,059 ​ 4,593 ​ Weighted average daily borrowings during the period ended ​ 13,287 ​ 15,829 ​ Maximum daily borrowings during the period ended ​ 39,381 ​ 57,107 ​ Weighted average interest rate during the period ended ​ 6.2 % 5.9 % Interest rate at end of the period ​ 6.2 % 6.3 % ​ (h) (i) (j) (k) The all-in weighted average interest rate, inclusive of the impact of the forward starting swaps and treasury locks, was 3.32% . (l) (m) . (n) 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, 2024 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Fixed Total Variable Total Total Total Year ​ Secured Debt ​ Secured Debt ​ Secured Debt ​ Unsecured Debt ​ Debt 2024 ​ $ 97,222 ​ $ — ​ $ 97,222 ​ $ 405,644 ​ $ 502,866 2025 ​ ​ 178,323 ​ ​ — ​ ​ 178,323 ​ ​ 27,059 ​ ​ 205,382 2026 ​ 56,672 ​ — ​ 56,672 ​ 300,000 ​ 356,672 2027 ​ 6,939 ​ — ​ 6,939 ​ 650,000 ​ 656,939 2028 ​ 166,526 ​ — ​ 166,526 ​ 300,000 ​ 466,526 2029 ​ 315,811 ​ — ​ 315,811 ​ 300,000 ​ 615,811 2030 ​ 230,596 ​ — ​ 230,596 ​ 600,000 ​ 830,596 2031 ​ 160,930 ​ — ​ 160,930 ​ 600,000 ​ 760,930 2032 ​ — ​ 27,000 ​ 27,000 ​ 400,000 ​ 427,000 2033 ​ — ​ ​ ​ — ​ 650,000 ​ 650,000 Thereafter ​ — ​ — ​ — ​ 300,000 ​ 300,000 Subtotal ​ 1,213,019 ​ 27,000 ​ 1,240,019 ​ 4,532,703 ​ 5,772,722 Non-cash (a) ​ (3,196) ​ (44) ​ (3,240) ​ (7,154) ​ (10,394) Total ​ $ 1,209,823 ​ $ 26,956 ​ $ 1,236,779 ​ $ 4,525,549 ​ $ 5,762,328 (a) Includes the unamortized balance of fair market value adjustments, premiums/discounts and deferred financing costs . The Company amortized $1.2 million and $1.0 million, respectively, during the three months ended March 31, 2024 and 2023, of deferred financing costs into Interest expense. We were in compliance with the covenants of our debt instruments at March 31, 2024.

INCOME_(LOSS) PER SHARE

INCOME/(LOSS) PER SHARE	3 Months Ended
	Mar. 31, 2024
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): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ 2024 2023 ​ Numerator for income/(loss) per share: ​ ​ ​ ​ ​ ​ Net income/(loss) ​ $ 46,310 ​ $ 32,925 ​ Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (3,149) ​ (1,953) ​ Net (income)/loss attributable to noncontrolling interests ​ (12) ​ (8) ​ Net income/(loss) attributable to UDR, Inc. ​ 43,149 ​ 30,964 ​ Distributions to preferred stockholders — Series E (Convertible) ​ (1,231) ​ (1,183) ​ Income/(loss) attributable to common stockholders - basic and diluted ​ ​ 41,918 ​ ​ 29,781 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator for income/(loss) per share: ​ ​ ​ Weighted average common shares outstanding ​ 329,244 ​ 329,165 ​ Unvested restricted stock awards ​ (421) ​ (376) ​ Denominator for basic income/(loss) per share ​ 328,823 ​ 328,789 ​ Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, unvested restricted stock and shares issuable upon settlement of forward sales agreements ​ 131 ​ 632 ​ Denominator for diluted income/(loss) per share ​ 328,954 ​ 329,421 ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) per weighted average common share: ​ ​ ​ Basic ​ $ 0.13 ​ $ 0.09 ​ Diluted ​ $ 0.13 ​ $ 0.09 ​ ​ 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, 2024 and 2023, 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, 2024, the Company did not sell any shares of common stock through its ATM program. As of March 31, 2024, we had 14.0 million shares of common stock available for future issuance under the ATM program. 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. For the three months ended March 31, 2024, the Company did not enter into any forward purchase agreements under its continuous equity program. ​ 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, 2024 and 2023 (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ ​ 2024 ​ 2023 ​ OP/DownREIT Units 24,418 21,323 Convertible preferred stock 2,908 2,909 Unvested LTIP Units and unvested restricted stock 131 632 ​

NONCONTROLLING INTERESTS

NONCONTROLLING INTERESTS	3 Months Ended
	Mar. 31, 2024
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 at December 31, 2023 $ 961,087 ​ Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (14,629) ​ Conversion of OP Units/DownREIT Units to Common Stock or Cash ​ (7,288) ​ Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ 3,149 ​ Distributions to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (10,712) ​ Redeemable Long-Term and Short-Term Incentive Plan Units ​ ​ 5,356 ​ Allocation of other comprehensive income/(loss) ​ 348 ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership at March 31, 2024 ​ $ 937,311 ​ ​ 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, 2024
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, 2024 and December 31, 2023, are summarized as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at March 31, 2024, 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 ​ ​ 2024 (a) ​ 2024 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 235,382 ​ $ 225,512 ​ $ — ​ $ — ​ $ 225,512 Equity securities (c) ​ ​ 1,962 ​ ​ 1,962 ​ ​ 1,962 ​ ​ — ​ ​ — Derivatives - Interest rate contracts (d) ​ 9,425 ​ 9,425 ​ — ​ 9,425 ​ — Total assets ​ $ 246,769 ​ $ 236,899 ​ $ 1,962 ​ $ 9,425 ​ $ 225,512 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,214,095 ​ $ 1,119,833 ​ $ — ​ $ — ​ $ 1,119,833 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 ​ ​ 27,059 ​ ​ 27,059 ​ ​ — ​ ​ — ​ ​ 27,059 Commercial paper program ​ ​ 390,000 ​ ​ 390,000 ​ ​ — ​ ​ — ​ ​ 390,000 Unsecured notes ​ ​ 4,128,501 ​ ​ 3,603,760 ​ ​ — ​ ​ — ​ ​ 3,603,760 Total liabilities ​ $ 5,786,655 ​ $ 5,167,652 ​ $ — ​ $ — ​ $ 5,167,652 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 937,311 ​ $ 937,311 ​ $ — ​ $ 937,311 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at December 31, 2023, 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 ​ 2023 (a) ​ 2023 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 228,825 ​ $ 222,755 ​ $ — ​ $ — ​ $ 222,755 Equity securities (c) ​ ​ 7,210 ​ ​ 7,210 ​ ​ 7,210 ​ ​ — ​ ​ — Derivatives - Interest rate contracts (d) ​ 10,103 ​ 10,103 ​ — ​ 10,103 ​ — Total assets ​ $ 246,138 ​ $ 240,068 ​ $ 7,210 ​ $ 10,103 ​ $ 222,755 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,215,228 ​ $ 1,124,140 ​ $ — ​ $ — ​ $ 1,124,140 Secured debt instruments - variable rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ 40,017 ​ 40,017 ​ — ​ — ​ 40,017 Tax-exempt secured notes payable ​ 27,000 ​ 27,000 ​ — ​ — ​ 27,000 Unsecured debt instruments: (e) ​ ​ ​ ​ ​ ​ ​ Working capital credit facility ​ ​ 4,593 ​ ​ 4,593 ​ ​ — ​ ​ — ​ ​ 4,593 Commercial paper program ​ ​ 408,075 ​ ​ 408,075 ​ ​ — ​ ​ — ​ ​ 408,075 Unsecured notes ​ ​ 4,129,010 ​ ​ 3,611,697 ​ ​ — ​ ​ — ​ ​ 3,611,697 Total liabilities ​ $ 5,823,923 ​ $ 5,215,522 ​ $ — ​ $ — ​ $ 5,215,522 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 961,087 ​ $ 961,087 ​ $ — ​ $ 961,087 ​ $ — (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. The investment is valued at the market price on March 31, 2024 and December 31, 2023. The Company currently classifies the investment as Level 1 in the fair value hierarchy. (d) See Note 11, Derivatives and Hedging Activity . (e) See Note 7, Secured and Unsecured Debt, Net . (f) See Note 9, Noncontrolling Interests. There were no transfers into or out of any of the levels of the fair value hierarchy during the three months ended March 31, 2024. 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, 2024 and December 31, 2023, 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, 2024 and December 31, 2023, 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, 2024
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 into earnings in the period that the hedged forecasted transaction affects earnings. During the three months ended March 31, 2024 and 2023, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt. Amounts reported in Accumulated other comprehensive income/(loss), net Interest expense As of March 31, 2024, 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 ​ 4 ​ $ 282,380 ​ During the three months ended March 31, 2024, the Company entered into and settled a treasury lock arrangement with a notional value of $150.0 million to hedge the interest rate risk associated with a future debt issuance, resulting in a deferred gain of $5.0 million which is recorded in Accumulated other comprehensive income/(loss), ​ 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, 2024, 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, 2024 and December 31, 2023 ( 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, ​ ​ 2024 ​ 2023 ​ 2024 ​ 2023 Derivatives designated as hedging instruments: ​ ​ ​ ​ Interest rate products ​ $ 9,425 ​ $ 10,103 ​ $ — ​ $ — ​ 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, 2024 and 2023 ( 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 2024 2023 2024 2023 2024 2023 Three Months Ended March 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate products ​ $ 6,664 ​ $ (273) ​ $ 1,995 ​ $ 1,369 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ ​ 2024 ​ 2023 Total amount of Interest expense ​ $ 48,062 ​ $ 43,742 ​ 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, 2024 and December 31, 2023 (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, 2024 ​ $ 9,425 ​ $ — ​ $ 9,425 ​ $ — ​ $ — ​ $ 9,425 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ $ 10,103 ​ $ — ​ $ 10,103 ​ $ — ​ $ — ​ $ 10,103 (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.

STOCK BASED COMPENSATION

STOCK BASED COMPENSATION	3 Months Ended
	Mar. 31, 2024
STOCK BASED COMPENSATION
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 $7.3 million and $8.2 million during the three months ended March 31, 2024 and 2023, respectively, which are included in General and Administrative

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2024
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES	13. COMMITMENTS AND CONTINGENCIES Commitments The following summarizes the Company’s commitments at March 31, 2024 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number ​ UDR's ​ UDR's Remaining ​ ​ ​ Properties ​ Investment (a) ​ Commitment ​ Real estate commitments ​ ​ ​ ​ ​ ​ ​ ​ ​ Wholly-owned — under development 1 ​ $ 126,163 ​ $ 7,837 Wholly-owned — redevelopment (b) 10 ​ ​ 51,420 ​ ​ 113,527 Other unconsolidated investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ Real estate technology and sustainability investments (c) ​ - ​ ​ 57,140 ​ ​ 48,860 ​ Total ​ $ 234,723 ​ $ 170,224 (a) Represents UDR’s investment as of March 31, 2024. (b) Projects consist of unit renovations and/or renovation of related common area amenities. (c) As of March 31, 2024, the investments were recorded in either Investment in and advances to unconsolidated joint ventures, net or Other Assets on the Consolidated Balance Sheets . ​ 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. We have been named as a defendant in a number of cases alleging antitrust violations by RealPage, Inc., a vendor providing revenue management software products, and various owners or managers of multifamily housing, which cases have been consolidated in the United States Court for the Middle District of Tennessee with the Second Amended Complaint filed September 7, 2023 and a case with similar allegations that has been filed by the District of Columbia on November 1, 2023 in the Superior Court of the District of Columbia. These cases seek injunctive relief as well as monetary damages. We are also aware that governmental investigations regarding antitrust matters in the multifamily industry are occurring. We believe that there are defenses, both factual and legal, to the allegations in such cases and we intend to vigorously defend such suits. As all of the above proceedings are in the early stages, it is not possible for us to predict the outcome or to estimate the amount of loss, if any, that may be associated with an adverse decision in any of these cases or any case that may be brought based on the investigations.

REPORTABLE SEGMENTS

REPORTABLE SEGMENTS	3 Months Ended
	Mar. 31, 2024
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, 2023 and held as of March 31, 2024. 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, 2024 and 2023. ​ 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 monthly as the management services are provided and the fees are earned or upon a transaction whereby the Company earns a fee. 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, 2024 and 2023, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, (a) ​ 2024 2023 Reportable apartment home segment lease revenue ​ ​ ​ ​ ​ ​ Same-Store Communities ​ ​ West Region ​ $ 117,899 ​ $ 114,289 Mid-Atlantic Region ​ 76,811 ​ 74,122 Northeast Region ​ 80,330 ​ 77,342 Southeast Region ​ 56,784 ​ 55,799 Southwest Region ​ 37,615 ​ 37,678 Non-Mature Communities/Other ​ 29,740 ​ 27,787 Total segment and consolidated lease revenue ​ $ 399,179 ​ $ 387,017 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment other revenue ​ ​ ​ ​ ​ ​ Same-Store Communities ​ ​ West Region ​ $ 2,974 ​ $ 2,783 Mid-Atlantic Region ​ 3,124 ​ 2,472 Northeast Region ​ 1,735 ​ 1,742 Southeast Region ​ 2,414 ​ 2,133 Southwest Region ​ 1,566 ​ 1,379 Non-Mature Communities/Other ​ 677 ​ 781 Total segment and consolidated other revenue ​ $ 12,490 ​ $ 11,290 ​ ​ ​ ​ ​ ​ ​ Total reportable apartment home segment rental income ​ ​ ​ ​ ​ ​ Same-Store Communities ​ ​ West Region ​ $ 120,873 ​ $ 117,072 Mid-Atlantic Region ​ 79,935 ​ 76,594 Northeast Region ​ 82,065 ​ 79,084 Southeast Region ​ 59,198 ​ 57,932 Southwest Region ​ 39,181 ​ 39,057 Non-Mature Communities/Other ​ 30,417 ​ 28,568 Total segment and consolidated rental income ​ $ 411,669 ​ $ 398,307 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment NOI ​ ​ Same-Store Communities ​ ​ West Region ​ $ 89,413 ​ $ 88,369 Mid-Atlantic Region ​ 54,705 ​ 53,441 Northeast Region ​ 52,634 ​ 52,398 Southeast Region ​ 40,275 ​ 39,785 Southwest Region ​ 24,791 ​ 24,600 Non-Mature Communities/Other ​ 17,578 ​ 16,910 Total segment and consolidated NOI ​ 279,396 ​ 275,503 Reconciling items: ​ ​ Joint venture management and other fees ​ 1,965 ​ 1,242 Property management ​ (13,379) ​ (12,945) Other operating expenses ​ (6,828) ​ (3,032) Real estate depreciation and amortization ​ (169,858) ​ (169,300) General and administrative ​ (17,810) ​ (17,480) Casualty-related (charges)/recoveries, net ​ (6,278) ​ (4,156) Other depreciation and amortization ​ (4,316) ​ (3,649) Gain/(loss) on sale of real estate owned ​ ​ 16,867 ​ ​ 1 Income/(loss) from unconsolidated entities ​ 9,085 ​ 9,707 Interest expense ​ (48,062) ​ (43,742) Interest income and other income/(expense), net ​ 5,865 ​ 1,010 Tax (provision)/benefit, net ​ (337) ​ (234) Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (3,149) ​ (1,953) Net (income)/loss attributable to noncontrolling interests ​ (12) ​ (8) Net income/(loss) attributable to UDR, Inc. ​ $ 43,149 ​ $ 30,964 (a) Same-Store Community population consisted of 51,802 apartment homes. ​ The following table details the assets of UDR’s reportable segments as of March 31, 2024 and December 31, 2023 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Reportable apartment home segment assets: ​ ​ Same-Store Communities (a): ​ ​ West Region ​ $ 4,376,985 ​ $ 4,366,038 Mid-Atlantic Region ​ 3,214,861 ​ 3,205,036 Northeast Region ​ 3,899,854 ​ 3,890,762 Southeast Region ​ 1,599,068 ​ 1,589,605 Southwest Region ​ 1,334,198 ​ 1,330,063 Non-Mature Communities/Other ​ 1,566,230 ​ 1,642,355 Total segment assets ​ 15,991,196 ​ 16,023,859 Accumulated depreciation ​ (6,407,111) ​ (6,267,830) Total segment assets — net book value ​ 9,584,085 ​ 9,756,029 Reconciling items: ​ ​ Cash and cash equivalents ​ 2,116 ​ 2,922 Restricted cash ​ 29,850 ​ 31,944 Notes receivable, net ​ 235,382 ​ 228,825 Investment in and advances to unconsolidated joint ventures, net ​ 954,301 ​ 952,934 Operating lease right-of-use assets ​ ​ 189,729 ​ ​ 190,619 Other assets ​ 195,025 ​ 209,969 Total consolidated assets ​ $ 11,190,488 ​ $ 11,373,242 (a) Same-Store Community population consisted of 51,802 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, 2024
SIGNIFICANT ACCOUNTING POLICIES
Recent Accounting Pronouncements	Recent Accounting Pronouncements In March 2024, the SEC issued final rules on the enhancement and standardization of climate-related disclosures. The rules require disclosure of, among other things: material climate-related risks; activities to mitigate or adapt to such risks; governance and management of such risks; and material greenhouse gas emissions from operations owned or controlled (Scope 1) and/or indirect emissions from purchased energy consumed in operations (Scope 2). Additionally, the rules require disclosure in the notes to the financial statements of the effects of severe weather events and other natural conditions, subject to certain materiality thresholds. The rules will become effective for the Company on a phased-in timeline starting in the year ended December 31, 2025. While the SEC has voluntarily stayed the rules, the Company is currently evaluating the effect the rules will have on its financial statement disclosures. ​ In December 2023, the Financial Accounting Standards Board (“FASB”) issued 2023-09, Income Taxes (Topic 740) – Improvements to Income Tax Disclosures , ​ In November 2023, , Segment Reporting (Topic 280) – Improvements to Reportable Segments Disclosures
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 been transferred by the Company, 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 Accounting Standards Codification (“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 (a) ​ March 31, March 31, December 31, ​ ​ 2024 ​ 2024 ​ 2023 Notes due October 2024 (b) ​ 10.50 % $ 100,859 ​ $ 98,271 Note due December 2024 (c) ​ 12.00 % ​ 38,411 ​ ​ 37,022 Note due December 2026 (d) ​ 11.00 % ​ 66,317 ​ ​ 64,608 Note due December 2026 (e) ​ 11.00 % ​ 26,872 ​ ​ 26,164 Notes due June 2027 (f) ​ 18.00 % ​ 3,907 ​ ​ 3,737 Notes receivable ​ ​ ​ ​ 236,366 ​ ​ 229,802 Allowance for credit losses ​ ​ ​ ​ (984) ​ ​ (977) Total notes receivable, net ​ $ 235,382 ​ $ 228,825 (a) Outstanding note amounts include any accrued and unpaid interest, as applicable. (b) The Company has two loans (the “Notes”) with a joint venture that owns a 478 apartment home operating community located in Philadelphia, Pennsylvania with an aggregate commitment of $93.5 million (exclusive of accrued interest), all of which has been funded. The Notes are subordinate to the senior construction loan, but senior to the equity in the borrower. Currently, the Notes have a scheduled maturity date in October 2024, with two remaining one-year extension options. In April 2024, the joint venture refinanced the senior construction loan with a new loan that matures in April 2026, with a one year extension option subject to certain conditions. (c) The Company has a secured note with an unaffiliated third party with an aggregate commitment of $32.5 million, of which $31.8 million was funded as of March 31, 2024. Interest payments are due monthly, with the exception of payments from June 2022 to December 2024, which are accrued and added to the principal balance and will be due at maturity of the note. 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) December 2024. (d) The Company has a secured mezzanine loan with a third party developer of a 482 apartment home community located in Riverside, California, which is expected to be completed in 2025, with an aggregate commitment of $59.7 million (exclusive of accrued interest), all of which has been funded. Interest payments accrue for 36 months and are due monthly after the loan has been outstanding for 36 months . The secured mezzanine loan has a scheduled maturity date in December 2026, with two one-year extension options. (e) The Company has a secured mezzanine loan with a third party developer of a 237 apartment home community located in Menifee, California, which is expected to be completed in 2025, with an aggregate commitment of $24.4 million (exclusive of accrued interest), all of which has been funded. Interest payments accrue for 36 months and are due monthly after the loan has been outstanding for 36 months . The secured mezzanine loan has a scheduled maturity date in December 2026, with two one-year extension options. (f) The Company and a syndicate of lenders previously entered into a $16.0 million secured credit facility with an unaffiliated third party. In 2023, the secured credit facility was amended to provide a new term loan in the amount of $19.0 million, and the Company’s commitment was increased from $1.5 million to $3.0 million (exclusive of accrued interest) , all of which has been funded. Interest payments accrue and are due at maturity of the facility. The facility is secured by substantially all of the borrower’s assets and matures at the earliest of the following: (a) acceleration in the event of default; or (b) June 2027. The Company recognized $6.3 million and $1.6 million of interest income for the notes receivable described above during the three months ended March 31, 2024 and 2023, 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, 2024 and 2023, 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, 2024 and December 31, 2023, 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, 2024. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2020 through 2022 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
Lease Receivables	Lease Receivables ​ During the three months ended March 31, 2024 and 2023, the Company performed an analysis in accordance with the ASC 842, Leases, guidance to assess the collectibility of its operating lease receivables. 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 collection of lease payments is 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 of March 31, 2024, the Company’s multifamily tenant lease receivables balance, net of its reserve, was approximately $7.7 million, including its share from unconsolidated joint ventures. The Company’s retail tenant lease receivables balance (exclusive of straight-line rent receivables), net of its reserve, was approximately $0.4 million, including its share from unconsolidated joint ventures, as of March 31, 2024.

SIGNIFICANT ACCOUNTING POLICI_3

SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2024
SIGNIFICANT ACCOUNTING POLICIES
Summary of notes receivable, net	The following table summarizes our Notes receivable, net dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate at ​ Balance Outstanding (a) ​ March 31, March 31, December 31, ​ ​ 2024 ​ 2024 ​ 2023 Notes due October 2024 (b) ​ 10.50 % $ 100,859 ​ $ 98,271 Note due December 2024 (c) ​ 12.00 % ​ 38,411 ​ ​ 37,022 Note due December 2026 (d) ​ 11.00 % ​ 66,317 ​ ​ 64,608 Note due December 2026 (e) ​ 11.00 % ​ 26,872 ​ ​ 26,164 Notes due June 2027 (f) ​ 18.00 % ​ 3,907 ​ ​ 3,737 Notes receivable ​ ​ ​ ​ 236,366 ​ ​ 229,802 Allowance for credit losses ​ ​ ​ ​ (984) ​ ​ (977) Total notes receivable, net ​ $ 235,382 ​ $ 228,825 (a) Outstanding note amounts include any accrued and unpaid interest, as applicable. (b) The Company has two loans (the “Notes”) with a joint venture that owns a 478 apartment home operating community located in Philadelphia, Pennsylvania with an aggregate commitment of $93.5 million (exclusive of accrued interest), all of which has been funded. The Notes are subordinate to the senior construction loan, but senior to the equity in the borrower. Currently, the Notes have a scheduled maturity date in October 2024, with two remaining one-year extension options. In April 2024, the joint venture refinanced the senior construction loan with a new loan that matures in April 2026, with a one year extension option subject to certain conditions. (c) The Company has a secured note with an unaffiliated third party with an aggregate commitment of $32.5 million, of which $31.8 million was funded as of March 31, 2024. Interest payments are due monthly, with the exception of payments from June 2022 to December 2024, which are accrued and added to the principal balance and will be due at maturity of the note. 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) December 2024. (d) The Company has a secured mezzanine loan with a third party developer of a 482 apartment home community located in Riverside, California, which is expected to be completed in 2025, with an aggregate commitment of $59.7 million (exclusive of accrued interest), all of which has been funded. Interest payments accrue for 36 months and are due monthly after the loan has been outstanding for 36 months . The secured mezzanine loan has a scheduled maturity date in December 2026, with two one-year extension options. (e) The Company has a secured mezzanine loan with a third party developer of a 237 apartment home community located in Menifee, California, which is expected to be completed in 2025, with an aggregate commitment of $24.4 million (exclusive of accrued interest), all of which has been funded. Interest payments accrue for 36 months and are due monthly after the loan has been outstanding for 36 months . The secured mezzanine loan has a scheduled maturity date in December 2026, with two one-year extension options. (f) The Company and a syndicate of lenders previously entered into a $16.0 million secured credit facility with an unaffiliated third party. In 2023, the secured credit facility was amended to provide a new term loan in the amount of $19.0 million, and the Company’s commitment was increased from $1.5 million to $3.0 million (exclusive of accrued interest) , all of which has been funded. Interest payments accrue and are due at maturity of the facility. The facility is secured by substantially all of the borrower’s assets and matures at the earliest of the following: (a) acceleration in the event of default; or (b) June 2027.

REAL ESTATE OWNED (Tables)

REAL ESTATE OWNED (Tables)	3 Months Ended
	Mar. 31, 2024
REAL ESTATE OWNED
Summary of carrying amounts for real estate owned (at cost)	The following table summarizes the carrying amounts for our real estate owned (at cost) as of March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Land ​ $ 2,559,184 ​ $ 2,549,716 Depreciable property — held and used: ​ ​ ​ ​ Land improvements ​ 257,791 ​ 255,706 Building, improvements, and furniture, fixtures and equipment ​ 12,998,045 ​ 12,902,021 Real estate intangible assets ​ ​ 50,013 ​ ​ 50,013 Under development: ​ ​ Land and land improvements ​ 6,611 ​ 16,576 Building, improvements, and furniture, fixtures and equipment ​ 119,552 ​ 143,828 Real estate held for disposition: ​ ​ Land and land improvements ​ — ​ 13,734 Building, improvements, and furniture, fixtures and equipment ​ — ​ 92,265 Real estate owned ​ 15,991,196 ​ 16,023,859 Accumulated depreciation (a) ​ (6,407,111) ​ (6,267,830) Real estate owned, net ​ $ 9,584,085 ​ $ 9,756,029 (a) Accumulated depreciation is inclusive of $18.2 million and $17.2 million of accumulated amortization related to real estate intangible assets as of March 31, 2024 and December 31, 2023, respectively.

JOINT VENTURES AND PARTNERSHI_2

JOINT VENTURES AND PARTNERSHIPS (Tables)	3 Months Ended
	Mar. 31, 2024
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, 2024 and December 31, 2023 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Number of ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ Apartment ​ UDR's Weighted Average ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ Communities ​ Homes ​ Ownership Interest ​ ​ Investment at ​ Three Months Ended ​ March 31, March 31, ​ March 31, ​ December 31, March 31, December 31, ​ March 31, Joint Ventures 2024 2024 ​ 2024 2023 2024 2023 ​ 2024 2023 Operating: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ UDR/MetLife (a) ​ 13 ​ 2,837 ​ 50.2 % ​ 50.2 % ​ $ 219,387 ​ $ 225,195 ​ $ (1,846) ​ $ (1,350) UDR/LaSalle ​ 5 ​ 1,590 ​ 51.0 % ​ 51.0 % ​ ​ 281,314 ​ ​ 286,723 ​ ​ (2,878) ​ ​ — Total Joint Ventures ​ 18 4,427 ​ ​ ​ ​ $ 500,701 ​ $ 511,918 ​ $ (4,724) ​ $ (1,350) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of ​ Apartment ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) from investments ​ ​ Communities ​ Homes ​ Weighted ​ ​ ​ ​ ​ ​ ​ Investment at ​ Three Months Ended Developer Capital Program March 31, ​ March 31, ​ Average ​ Years To ​ UDR March 31, December 31, ​ March 31, and Real Estate Technology Investments (b) 2024 ​ 2024 ​ Rate ​ Maturity ​ Commitment (c) 2024 2023 2024 2023 Preferred equity investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ 21 ​ 4,545 ​ 9.3 % ​ 3.1 ​ $ 252,889 ​ $ 308,820 ​ $ 304,699 ​ $ 5,920 ​ $ 6,643 Development ​ 2 ​ 1,073 ​ 10.7 % ​ 3.3 ​ ​ 68,207 ​ ​ 85,315 ​ ​ 83,072 ​ ​ 2,243 ​ ​ 1,992 Total Preferred Equity Investments ​ 23 ​ 5,618 ​ 9.6 % ​ 3.1 ​ $ 321,096 ​ ​ 394,135 ​ ​ 387,771 ​ ​ 8,163 ​ ​ 8,635 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real estate technology and sustainability investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real estate technology and sustainability investments ​ N/A ​ N/A ​ N/A ​ ​ N/A ​ $ 86,000 ​ ​ 50,528 ​ ​ 44,382 ​ ​ 5,646 ​ ​ 935 Total Preferred Equity Investments and Real Estate Technology and Sustainability Investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 444,663 ​ ​ 432,153 ​ ​ 13,809 ​ ​ 9,570 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sold joint ventures and other investments ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ — ​ ​ — ​ ​ — ​ ​ 1,487 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total investment in and advances to unconsolidated joint ventures, net (a) ​ ​ ​ ​ $ 945,364 ​ $ 944,071 ​ $ 9,085 $ 9,707 (a) As of March 31, 2024 and December 31, 2023, the Company’s negative investment in one UDR/MetLife community of $8.9 million and $8.9 million, respectively, is recorded in Accounts payable, accrued expenses, and other liabilities on the Consolidated Balance Sheets. (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. At March 31, 2024, our preferred equity investment portfolio consisted of 23 communities located in various markets, consisting of 5,618 completed or under development homes. In addition, the Company’s preferred equity investments include four investments that receive a variable percentage of the value created from the project upon a capital or liquidating event. During the three months ended March 31, 2024, the Company did not enter into or fund any new preferred equity investments and no preferred equity investments were redeemed. (c) Represents UDR’s maximum funding commitment only and therefore excludes other activity such as income from investments. ​
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, 2024 and December 31, 2023 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ 2024 2023 Total real estate, net $ 3,180,973 $ 3,158,057 Investments, at fair value ​ ​ 304,826 ​ ​ 257,832 Cash and cash equivalents ​ 69,247 ​ 61,670 Other assets ​ ​ 135,491 ​ 146,976 Total assets $ 3,690,537 $ 3,624,535 ​ ​ ​ ​ ​ ​ ​ Third party debt, net ​ $ 2,027,146 ​ $ 2,012,816 Accounts payable and accrued liabilities ​ ​ 178,704 ​ ​ 171,502 Total liabilities ​ 2,205,850 ​ 2,184,318 Total equity $ 1,484,687 $ 1,440,217
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, 2024 and 2023 ( dollars in thousands : ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ 2024 2023 Total revenues $ 76,256 $ 60,675 Property operating expenses ​ 34,935 ​ 28,033 Real estate depreciation and amortization ​ 36,962 ​ 24,428 Operating income/(loss) ​ 4,359 ​ ​ 8,214 Interest expense ​ (24,537) ​ (23,951) Net unrealized/realized gain/(loss) on held investments ​ ​ 27,400 ​ ​ 9,789 Other income/(loss) ​ ​ (1,828) ​ ​ 2,322 Net income/(loss) $ 5,394 $ (3,626) ​

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2024
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, 2024 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Ground Leases 2024 ​ $ 9,332 2025 ​ ​ 12,442 2026 ​ ​ 12,442 2027 ​ ​ 12,442 2028 ​ ​ 12,442 Thereafter ​ ​ 405,452 Total future minimum lease payments (undiscounted) ​ ​ 464,552 Difference between future undiscounted cash flows and discounted cash flows ​ ​ (279,591) Total operating lease liabilities (discounted) ​ $ 184,961
Lessee - components of operating lease expenses	The components of operating lease expenses were as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2024 ​ 2023 Lease expense: ​ ​ ​ ​ ​ ​ Contractual lease expense ​ $ 3,350 ​ $ 3,292 Variable lease expense (a) ​ ​ 40 ​ ​ 28 Total operating lease expense (b)(c) ​ $ 3,390 ​ $ 3,320 (a) Variable lease expense includes adjustments such as changes in the consumer price index and payments based on a percentage of a community’s revenue. (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, 2024, Operating lease right-of-use assets and Operating lease liabilities amortized by $0.9 million and $0.9 million, respectively. For the three months ended March 31, 2023, 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 less than $0.1 million and less than $0.1 million of total operating lease expense during the three months ended March 31, 2024 and 2023, respectively.
Lessor - Future minimum lease payments	Future minimum lease payments from our retail and commercial leases as of March 31, 2024 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ Retail and Commercial Leases 2024 ​ $ 19,844 2025 ​ ​ 24,675 2026 ​ ​ 21,896 2027 ​ ​ 18,252 2028 ​ ​ 15,464 Thereafter ​ ​ 59,571 Total future minimum lease payments (a) ​ $ 159,702 (a)

SECURED AND UNSECURED DEBT, N_2

SECURED AND UNSECURED DEBT, NET (Tables)	3 Months Ended
	Mar. 31, 2024
Secured and Unsecured Debt
Schedule of debt instruments	The following is a summary of our secured and unsecured debt at March 31, 2024 and December 31, 2023 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal Outstanding ​ As of March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Average ​ Number of ​ ​ March 31, ​ December 31, ​ Interest ​ Years to ​ Communities ​ 2024 2023 Rate Maturity Encumbered Secured Debt: ​ ​ ​ ​ ​ ​ ​ Fixed Rate Debt ​ ​ Mortgage notes payable (a) ​ $ 1,213,019 ​ $ 1,213,751 3.48 % 4.4 20 Deferred financing costs and other non-cash adjustments (b) ​ (3,196) ​ (3,009) Total fixed rate secured debt, net ​ 1,209,823 ​ 1,210,742 3.42 % 4.4 20 Variable Rate Debt ​ ​ Mortgage notes payable (c) ​ — ​ 40,017 — % — — Tax-exempt secured notes payable (d) ​ 27,000 ​ 27,000 4.05 % 8.0 1 Deferred financing costs ​ (44) ​ (46) Total variable rate secured debt, net ​ 26,956 ​ 66,971 4.08 % 8.0 1 Total Secured Debt, net ​ 1,236,779 ​ 1,277,713 3.44 % 4.5 21 Unsecured Debt: ​ ​ Variable Rate Debt ​ ​ Borrowings outstanding under unsecured credit facility due January 2026 (e) (n) ​ — ​ — — % 1.8 Borrowings outstanding under unsecured commercial paper program due April 2024 (f) (n) ​ ​ 390,000 ​ ​ 408,075 ​ 5.53 % 0.1 ​ ​ Borrowings outstanding under unsecured working capital credit facility due January 2025 ​ 27,059 ​ 4,593 6.21 % 0.8 Term Loan due January 2027 (e) (n) ​ 87,500 ​ — 6.24 % 2.8 Fixed Rate Debt ​ ​ Term Loan due January 2027 (e) (n) ​ ​ 262,500 ​ 350,000 2.68 % 2.8 ​ ​ 8.50% Debentures due September 2024 ​ 15,644 ​ 15,644 8.50 % 0.5 2.95% Medium-Term Notes due September 2026 (h) (n) ​ 300,000 ​ 300,000 2.89 % 2.4 3.50% Medium-Term Notes due July 2027 (net of discounts of $229 and $247, respectively) (i) (n) ​ ​ 299,771 ​ ​ 299,753 ​ 4.03 % 3.3 ​ ​ 3.50% Medium-Term Notes due January 2028 (net of discounts of $450 and $479, respectively) (n) ​ ​ 299,550 ​ ​ 299,521 ​ 3.50 % 3.8 ​ ​ 4.40% Medium-Term Notes due January 2029 (net of discounts of $3 and $3, respectively) (j) (n) ​ ​ 299,997 ​ ​ 299,997 ​ 4.27 % 4.8 ​ ​ 3.20% Medium-Term Notes due January 2030 (net of premiums of $7,951 and $8,294, respectively) (k) (n) ​ ​ 607,951 ​ ​ 608,294 ​ 3.32 % 5.8 ​ ​ 3.00% Medium-Term Notes due August 2031 (net of premiums of $8,810 and $9,109, respectively) (l) (n) ​ ​ 608,810 ​ ​ 609,109 ​ 3.01 % 7.4 ​ ​ 2.10% Medium-Term Notes due August 2032 (net of discounts of $294 and $303, respectively) (n) ​ ​ 399,706 ​ ​ 399,697 ​ 2.10 % 8.3 ​ ​ 1.90% Medium-Term Notes due March 2033 (net of discounts of $1,079 and $1,110, respectively) (n) ​ ​ 348,921 ​ ​ 348,890 ​ 1.90 % 9.0 ​ ​ 2.10% Medium-Term Notes due June 2033 (net of discounts of $916 and $941, respectively) (n) ​ ​ 299,084 ​ ​ 299,059 ​ 2.10 % 9.2 ​ ​ 3.10% Medium-Term Notes due November 2034 (net of discounts of $934 and $956, respectively) (m) (n) ​ ​ 299,066 ​ ​ 299,044 ​ 3.13 % 10.6 ​ ​ Other ​ 1 ​ 2 Deferred financing costs ​ (20,011) ​ (20,682) Total Unsecured Debt, net ​ 4,525,549 ​ 4,520,996 3.36 % 5.7 Total Debt, net ​ $ 5,762,328 ​ $ 5,798,709 3.38 % 5.4
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, 2024 are as follows (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Fixed Total Variable Total Total Total Year ​ Secured Debt ​ Secured Debt ​ Secured Debt ​ Unsecured Debt ​ Debt 2024 ​ $ 97,222 ​ $ — ​ $ 97,222 ​ $ 405,644 ​ $ 502,866 2025 ​ ​ 178,323 ​ ​ — ​ ​ 178,323 ​ ​ 27,059 ​ ​ 205,382 2026 ​ 56,672 ​ — ​ 56,672 ​ 300,000 ​ 356,672 2027 ​ 6,939 ​ — ​ 6,939 ​ 650,000 ​ 656,939 2028 ​ 166,526 ​ — ​ 166,526 ​ 300,000 ​ 466,526 2029 ​ 315,811 ​ — ​ 315,811 ​ 300,000 ​ 615,811 2030 ​ 230,596 ​ — ​ 230,596 ​ 600,000 ​ 830,596 2031 ​ 160,930 ​ — ​ 160,930 ​ 600,000 ​ 760,930 2032 ​ — ​ 27,000 ​ 27,000 ​ 400,000 ​ 427,000 2033 ​ — ​ ​ ​ — ​ 650,000 ​ 650,000 Thereafter ​ — ​ — ​ — ​ 300,000 ​ 300,000 Subtotal ​ 1,213,019 ​ 27,000 ​ 1,240,019 ​ 4,532,703 ​ 5,772,722 Non-cash (a) ​ (3,196) ​ (44) ​ (3,240) ​ (7,154) ​ (10,394) Total ​ $ 1,209,823 ​ $ 26,956 ​ $ 1,236,779 ​ $ 4,525,549 ​ $ 5,762,328 (a) Includes the unamortized balance of fair market value adjustments, premiums/discounts and deferred financing costs . The Company amortized $1.2 million and $1.0 million, respectively, during the three months ended March 31, 2024 and 2023, of deferred financing costs into Interest expense.
Commercial Paper
Secured and Unsecured Debt
Schedule of short-term bank borrowings	The following is a summary of short-term bank borrowings under the unsecured commercial paper program at March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Total unsecured commercial paper program $ 700,000 ​ $ 700,000 ​ Borrowings outstanding at end of period ​ 390,000 ​ 408,075 ​ Weighted average daily borrowings during the period ended ​ 423,478 ​ 384,068 ​ Maximum daily borrowings during the period ended ​ 560,000 ​ 505,000 ​ Weighted average interest rate during the period ended ​ 5.6 % 5.4 % Interest rate at end of the period ​ 5.5 % 5.7 %
Revolving Credit Facility
Secured and Unsecured Debt
Schedule of short-term bank borrowings	The following is a summary of short-term bank borrowings under the Revolving Credit Facility at March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 2023 ​ 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 ​ — ​ 2,055 ​ Maximum daily borrowings during the period ended ​ — ​ 250,000 ​ Weighted average interest rate during the period ended ​ — % 5.6 % Interest rate at end of the period ​ — % — % (1) Excludes $3.8 million and $2.3 million of letters of credit at March 31, 2024 and December 31, 2023, respectively .
Working capital credit facility
Secured and Unsecured Debt
Schedule of short-term bank borrowings	The following is a summary of short-term bank borrowings under the Working Capital Credit Facility at March 31, 2024 and December 31, 2023 (dollars in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Total working capital credit facility ​ $ 75,000 ​ $ 75,000 ​ Borrowings outstanding at end of period ​ 27,059 ​ 4,593 ​ Weighted average daily borrowings during the period ended ​ 13,287 ​ 15,829 ​ Maximum daily borrowings during the period ended ​ 39,381 ​ 57,107 ​ Weighted average interest rate during the period ended ​ 6.2 % 5.9 % Interest rate at end of the period ​ 6.2 % 6.3 %

INCOME_(LOSS) PER SHARE (Tables

INCOME/(LOSS) PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2024
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): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ 2024 2023 ​ Numerator for income/(loss) per share: ​ ​ ​ ​ ​ ​ Net income/(loss) ​ $ 46,310 ​ $ 32,925 ​ Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (3,149) ​ (1,953) ​ Net (income)/loss attributable to noncontrolling interests ​ (12) ​ (8) ​ Net income/(loss) attributable to UDR, Inc. ​ 43,149 ​ 30,964 ​ Distributions to preferred stockholders — Series E (Convertible) ​ (1,231) ​ (1,183) ​ Income/(loss) attributable to common stockholders - basic and diluted ​ ​ 41,918 ​ ​ 29,781 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator for income/(loss) per share: ​ ​ ​ Weighted average common shares outstanding ​ 329,244 ​ 329,165 ​ Unvested restricted stock awards ​ (421) ​ (376) ​ Denominator for basic income/(loss) per share ​ 328,823 ​ 328,789 ​ Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, unvested restricted stock and shares issuable upon settlement of forward sales agreements ​ 131 ​ 632 ​ Denominator for diluted income/(loss) per share ​ 328,954 ​ 329,421 ​ ​ ​ ​ ​ ​ ​ ​ ​ Income/(loss) per weighted average common share: ​ ​ ​ Basic ​ $ 0.13 ​ $ 0.09 ​ Diluted ​ $ 0.13 ​ $ 0.09 ​
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, 2024 and 2023 (in thousands) ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ ​ March 31, ​ ​ ​ 2024 ​ 2023 ​ OP/DownREIT Units 24,418 21,323 Convertible preferred stock 2,908 2,909 Unvested LTIP Units and unvested restricted stock 131 632 ​

NONCONTROLLING INTERESTS (Table

NONCONTROLLING INTERESTS (Tables)	3 Months Ended
	Mar. 31, 2024
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 at December 31, 2023 $ 961,087 ​ Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (14,629) ​ Conversion of OP Units/DownREIT Units to Common Stock or Cash ​ (7,288) ​ Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ 3,149 ​ Distributions to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (10,712) ​ Redeemable Long-Term and Short-Term Incentive Plan Units ​ ​ 5,356 ​ Allocation of other comprehensive income/(loss) ​ 348 ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership at March 31, 2024 ​ $ 937,311 ​

FAIR VALUE OF DERIVATIVES AND_2

FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2024
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, 2024 and December 31, 2023, are summarized as follows (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at March 31, 2024, 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 ​ ​ 2024 (a) ​ 2024 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 235,382 ​ $ 225,512 ​ $ — ​ $ — ​ $ 225,512 Equity securities (c) ​ ​ 1,962 ​ ​ 1,962 ​ ​ 1,962 ​ ​ — ​ ​ — Derivatives - Interest rate contracts (d) ​ 9,425 ​ 9,425 ​ — ​ 9,425 ​ — Total assets ​ $ 246,769 ​ $ 236,899 ​ $ 1,962 ​ $ 9,425 ​ $ 225,512 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,214,095 ​ $ 1,119,833 ​ $ — ​ $ — ​ $ 1,119,833 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 ​ ​ 27,059 ​ ​ 27,059 ​ ​ — ​ ​ — ​ ​ 27,059 Commercial paper program ​ ​ 390,000 ​ ​ 390,000 ​ ​ — ​ ​ — ​ ​ 390,000 Unsecured notes ​ ​ 4,128,501 ​ ​ 3,603,760 ​ ​ — ​ ​ — ​ ​ 3,603,760 Total liabilities ​ $ 5,786,655 ​ $ 5,167,652 ​ $ — ​ $ — ​ $ 5,167,652 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 937,311 ​ $ 937,311 ​ $ — ​ $ 937,311 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value at December 31, 2023, 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 ​ 2023 (a) ​ 2023 ​ (Level 1) ​ (Level 2) ​ (Level 3) Description: ​ ​ ​ ​ ​ ​ Notes receivable, net (b) ​ $ 228,825 ​ $ 222,755 ​ $ — ​ $ — ​ $ 222,755 Equity securities (c) ​ ​ 7,210 ​ ​ 7,210 ​ ​ 7,210 ​ ​ — ​ ​ — Derivatives - Interest rate contracts (d) ​ 10,103 ​ 10,103 ​ — ​ 10,103 ​ — Total assets ​ $ 246,138 ​ $ 240,068 ​ $ 7,210 ​ $ 10,103 ​ $ 222,755 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Secured debt instruments - fixed rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ $ 1,215,228 ​ $ 1,124,140 ​ $ — ​ $ — ​ $ 1,124,140 Secured debt instruments - variable rate: (e) ​ ​ ​ ​ ​ ​ Mortgage notes payable ​ 40,017 ​ 40,017 ​ — ​ — ​ 40,017 Tax-exempt secured notes payable ​ 27,000 ​ 27,000 ​ — ​ — ​ 27,000 Unsecured debt instruments: (e) ​ ​ ​ ​ ​ ​ ​ Working capital credit facility ​ ​ 4,593 ​ ​ 4,593 ​ ​ — ​ ​ — ​ ​ 4,593 Commercial paper program ​ ​ 408,075 ​ ​ 408,075 ​ ​ — ​ ​ — ​ ​ 408,075 Unsecured notes ​ ​ 4,129,010 ​ ​ 3,611,697 ​ ​ — ​ ​ — ​ ​ 3,611,697 Total liabilities ​ $ 5,823,923 ​ $ 5,215,522 ​ $ — ​ $ — ​ $ 5,215,522 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership (f) ​ $ 961,087 ​ $ 961,087 ​ $ — ​ $ 961,087 ​ $ — (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. The investment is valued at the market price on March 31, 2024 and December 31, 2023. The Company currently classifies the investment as Level 1 in the fair value hierarchy. (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, 2024
DERIVATIVES AND HEDGING ACTIVITY
Schedule of outstanding interest rate derivatives	As of March 31, 2024, 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 ​ 4 ​ $ 282,380 ​
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, 2024 and December 31, 2023 ( 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, ​ ​ 2024 ​ 2023 ​ 2024 ​ 2023 Derivatives designated as hedging instruments: ​ ​ ​ ​ Interest rate products ​ $ 9,425 ​ $ 10,103 ​ $ — ​ $ —
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, 2024 and 2023 ( 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 2024 2023 2024 2023 2024 2023 Three Months Ended March 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate products ​ $ 6,664 ​ $ (273) ​ $ 1,995 ​ $ 1,369 ​ $ — ​ $ —
Effect of Company's derivatives not designated as hedging instruments on the Consolidated Statements of Operations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, ​ ​ 2024 ​ 2023 Total amount of Interest expense ​ $ 48,062 ​ $ 43,742
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, 2024 and December 31, 2023 (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, 2024 ​ $ 9,425 ​ $ — ​ $ 9,425 ​ $ — ​ $ — ​ $ 9,425 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ $ 10,103 ​ $ — ​ $ 10,103 ​ $ — ​ $ — ​ $ 10,103 (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.

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
	Mar. 31, 2024
COMMITMENTS AND CONTINGENCIES
Summary of real estate commitments	The following summarizes the Company’s commitments at March 31, 2024 ( dollars in thousands ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number ​ UDR's ​ UDR's Remaining ​ ​ ​ Properties ​ Investment (a) ​ Commitment ​ Real estate commitments ​ ​ ​ ​ ​ ​ ​ ​ ​ Wholly-owned — under development 1 ​ $ 126,163 ​ $ 7,837 Wholly-owned — redevelopment (b) 10 ​ ​ 51,420 ​ ​ 113,527 Other unconsolidated investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ Real estate technology and sustainability investments (c) ​ - ​ ​ 57,140 ​ ​ 48,860 ​ Total ​ $ 234,723 ​ $ 170,224 (a) Represents UDR’s investment as of March 31, 2024. (b) Projects consist of unit renovations and/or renovation of related common area amenities. (c) As of March 31, 2024, the investments were recorded in either Investment in and advances to unconsolidated joint ventures, net or Other Assets on the Consolidated Balance Sheets .

REPORTABLE SEGMENTS (Tables)

REPORTABLE SEGMENTS (Tables)	3 Months Ended
	Mar. 31, 2024
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, 2024 and 2023, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ March 31, (a) ​ 2024 2023 Reportable apartment home segment lease revenue ​ ​ ​ ​ ​ ​ Same-Store Communities ​ ​ West Region ​ $ 117,899 ​ $ 114,289 Mid-Atlantic Region ​ 76,811 ​ 74,122 Northeast Region ​ 80,330 ​ 77,342 Southeast Region ​ 56,784 ​ 55,799 Southwest Region ​ 37,615 ​ 37,678 Non-Mature Communities/Other ​ 29,740 ​ 27,787 Total segment and consolidated lease revenue ​ $ 399,179 ​ $ 387,017 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment other revenue ​ ​ ​ ​ ​ ​ Same-Store Communities ​ ​ West Region ​ $ 2,974 ​ $ 2,783 Mid-Atlantic Region ​ 3,124 ​ 2,472 Northeast Region ​ 1,735 ​ 1,742 Southeast Region ​ 2,414 ​ 2,133 Southwest Region ​ 1,566 ​ 1,379 Non-Mature Communities/Other ​ 677 ​ 781 Total segment and consolidated other revenue ​ $ 12,490 ​ $ 11,290 ​ ​ ​ ​ ​ ​ ​ Total reportable apartment home segment rental income ​ ​ ​ ​ ​ ​ Same-Store Communities ​ ​ West Region ​ $ 120,873 ​ $ 117,072 Mid-Atlantic Region ​ 79,935 ​ 76,594 Northeast Region ​ 82,065 ​ 79,084 Southeast Region ​ 59,198 ​ 57,932 Southwest Region ​ 39,181 ​ 39,057 Non-Mature Communities/Other ​ 30,417 ​ 28,568 Total segment and consolidated rental income ​ $ 411,669 ​ $ 398,307 ​ ​ ​ ​ ​ ​ ​ Reportable apartment home segment NOI ​ ​ Same-Store Communities ​ ​ West Region ​ $ 89,413 ​ $ 88,369 Mid-Atlantic Region ​ 54,705 ​ 53,441 Northeast Region ​ 52,634 ​ 52,398 Southeast Region ​ 40,275 ​ 39,785 Southwest Region ​ 24,791 ​ 24,600 Non-Mature Communities/Other ​ 17,578 ​ 16,910 Total segment and consolidated NOI ​ 279,396 ​ 275,503 Reconciling items: ​ ​ Joint venture management and other fees ​ 1,965 ​ 1,242 Property management ​ (13,379) ​ (12,945) Other operating expenses ​ (6,828) ​ (3,032) Real estate depreciation and amortization ​ (169,858) ​ (169,300) General and administrative ​ (17,810) ​ (17,480) Casualty-related (charges)/recoveries, net ​ (6,278) ​ (4,156) Other depreciation and amortization ​ (4,316) ​ (3,649) Gain/(loss) on sale of real estate owned ​ ​ 16,867 ​ ​ 1 Income/(loss) from unconsolidated entities ​ 9,085 ​ 9,707 Interest expense ​ (48,062) ​ (43,742) Interest income and other income/(expense), net ​ 5,865 ​ 1,010 Tax (provision)/benefit, net ​ (337) ​ (234) Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership ​ (3,149) ​ (1,953) Net (income)/loss attributable to noncontrolling interests ​ (12) ​ (8) Net income/(loss) attributable to UDR, Inc. ​ $ 43,149 ​ $ 30,964 (a) Same-Store Community population consisted of 51,802 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, 2024 and December 31, 2023 (dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, ​ ​ 2024 ​ 2023 Reportable apartment home segment assets: ​ ​ Same-Store Communities (a): ​ ​ West Region ​ $ 4,376,985 ​ $ 4,366,038 Mid-Atlantic Region ​ 3,214,861 ​ 3,205,036 Northeast Region ​ 3,899,854 ​ 3,890,762 Southeast Region ​ 1,599,068 ​ 1,589,605 Southwest Region ​ 1,334,198 ​ 1,330,063 Non-Mature Communities/Other ​ 1,566,230 ​ 1,642,355 Total segment assets ​ 15,991,196 ​ 16,023,859 Accumulated depreciation ​ (6,407,111) ​ (6,267,830) Total segment assets — net book value ​ 9,584,085 ​ 9,756,029 Reconciling items: ​ ​ Cash and cash equivalents ​ 2,116 ​ 2,922 Restricted cash ​ 29,850 ​ 31,944 Notes receivable, net ​ 235,382 ​ 228,825 Investment in and advances to unconsolidated joint ventures, net ​ 954,301 ​ 952,934 Operating lease right-of-use assets ​ ​ 189,729 ​ ​ 190,619 Other assets ​ 195,025 ​ 209,969 Total consolidated assets ​ $ 11,190,488 ​ $ 11,373,242 (a) Same-Store Community population consisted of 51,802 apartment homes. ​

BASIS OF PRESENTATION (Details)

BASIS OF PRESENTATION (Details) shares in Millions	3 Months Ended
	Mar. 31, 2024 home community item shares
Consolidation And Basis Of Presentation
Number of real estate properties | community	168
Number of markets operating within | item	21
Number of apartment homes owned and consolidated | home	55,386
Joint venture, number of completed or to be completed homes in communities | home	10,045
Preferred equity investment,, number of apartment homes | home	5,618
Operating partnership outstanding units	190
United Dominion Reality L.P.
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner	176.5
General partnership units outstanding	0.1
General Partners' ownership (as a percent)	92.90%
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	13.5
Percentage of units outstanding in Partnership	7.10%
Non-affiliated Partners | UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating partnership outstanding units	10.9
Percentage of units outstanding in Partnership	33.60%
UDR, Inc.
Consolidation And Basis Of Presentation
General Partners' ownership (as a percent)	66.40%
Operating partnership outstanding units	21.5

SIGNIFICANT ACCOUNTING POLICI_4

SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accounting policies
Credit losses		$ (100)
Significant Accounting Policies
Allocation of other comprehensive income/(loss)	$ 348
Current income tax expense (benefit)	0
Net deferred tax assets/(liabilities)	(800)	(800)
Unrecognized tax benefit, accrued interest or penalties due to examination	0
Noncontrolling Interest
Significant Accounting Policies
Allocation of other comprehensive income/(loss)	300	(100)
Maximum
Accounting policies
Credit losses	(100)
Non-related party
Significant Accounting Policies
Interest income	6,300	1,600
Related party
Significant Accounting Policies
Interest income	0	$ 0
Multifamily tenant lease
Significant Accounting Policies
Tenant leases receivable, net	7,700
Retail tenant lease
Significant Accounting Policies
Tenant leases receivable, net	$ 400

SIGNIFICANT ACCOUNTING POLICI_5

SIGNIFICANT ACCOUNTING POLICIES - Notes Receivables (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2024	Mar. 31, 2024 USD ($) item home loan	Dec. 31, 2023 USD ($)
Accounting Policies [Line Items]
Notes receivable		$ 236,366	$ 229,802
Allowance for credit losses		(984)	(977)
Total notes receivable, net		$ 235,382	228,825
Number of loans | loan		2
Note due October 2024
Accounting Policies [Line Items]
Notes receivable		$ 100,859	98,271
Note receivable interest rate		10.50%
Aggregate commitment on note receivable		$ 93,500
Number of extension options | item		2
Term of notes receivable extension options		1 year
Note due December 2024
Accounting Policies [Line Items]
Notes receivable		$ 38,411	37,022
Note receivable interest rate		12%
Number of apartment homes | home		478
Aggregate commitment on note receivable		$ 32,500
Aggregate commitment funded on note receivable		31,800
Note maturity public capital threshold		5,000
Note due December 2026. | Home Community, Riverside, California
Accounting Policies [Line Items]
Notes receivable		$ 66,317	64,608
Note receivable interest rate		11%
Number of apartment homes | home		482
Aggregate commitment on note receivable		$ 59,700
Interest payment accrual		36 months
Number of extension options | item		2
Term of notes receivable extension options		1 year
Note due December 2026. | Home Community, Menifee, California
Accounting Policies [Line Items]
Number of apartment homes | home		237
Aggregate commitment on note receivable		$ 24,400
Interest payment accrual		36 months
Number of extension options | item		2
Term of notes receivable extension options		1 year
Note due December 2026 | Home Community, Menifee, California
Accounting Policies [Line Items]
Notes receivable		$ 26,872	26,164
Note receivable interest rate		11%
Note due June 2027
Accounting Policies [Line Items]
Notes receivable		$ 3,907	3,737
Note receivable interest rate		18%
Aggregate commitment on note receivable		$ 3,000
Increase in aggregate commitment on note receivable		1,500
Total revolving credit facility		$ 19,000	$ 16,000
Note Due on April 2026 | Subsequent Event
Accounting Policies [Line Items]
Term of notes receivable extension options	1 year

REAL ESTATE OWNED - Summarizes

REAL ESTATE OWNED - Summarizes the carrying amounts for our real estate owned (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Real estate owned
Land	$ 2,559,184	$ 2,549,716
Depreciable property - held and used:
Land improvements	257,791	255,706
Building, improvements, and furniture, fixtures and equipment	12,998,045	12,902,021
Real estate intangible assets	50,013	50,013
Under development:
Real estate under development	126,144	160,220
Real estate owned	15,991,196	16,023,859
Accumulated depreciation	(6,407,111)	(6,267,830)
Total real estate owned, net of accumulated depreciation	9,584,085	9,756,029
Accumulated amortization	18,200	17,200
Land and land improvements
Under development:
Real estate under development	6,611	16,576
Real estate assets held for sale		13,734
Building, improvements and furniture, fixtures and equipment
Under development:
Real estate under development	$ 119,552	143,828
Real estate assets held for sale		$ 92,265

REAL ESTATE OWNED - Additional

REAL ESTATE OWNED - Additional Information (Details) $ in Thousands	1 Months Ended		3 Months Ended
	Feb. 29, 2024 USD ($) home	Jan. 31, 2024 USD ($) home	Mar. 31, 2024 USD ($) state home community	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Real Estate Owned Disclosure
Number of real estate properties | community			168
Number of states in which there are owned and consolidated communities | state			13
Number of apartment homes owned and consolidated | home			55,386
Gain/(loss) on sale of real estate owned			$ 16,867	$ 1
Development costs excluding direct costs and capitalized interest			4,200	4,500
Capitalized interest during period			2,800	$ 2,200
Real estate intangible assets			50,013		$ 50,013
Total real estate owned, net of accumulated depreciation			$ 9,584,085		$ 9,756,029
214 Home Operating Community located in Arlington
Real Estate Owned Disclosure
Proceeds from sale of real estate	$ 100,000
Gain/(loss) on sale of real estate owned	$ 16,900
Number of apartment homes sold | home	214
173 Home Operating Community in Oakland, California
Real Estate Owned Disclosure
Number of apartment homes acquired | home		173
Real estate acquired, Purchase price		$ 1,400

JOINT VENTURES AND PARTNERSHI_3

JOINT VENTURES AND PARTNERSHIPS - Summary (Details)	3 Months Ended
	Mar. 31, 2024 USD ($) community home property item	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Unconsolidated entities
Number of communities | community	168
Assets	$ 11,190,488,000		$ 11,373,242,000
Liabilities	6,333,899,000		6,420,801,000
Total assets	11,190,488,000		11,373,242,000
Total liabilities	6,333,899,000		6,420,801,000
Investment in unconsolidated entities	945,364,000		944,071,000
Income/(loss) from investments	$ 9,085,000	$ 9,707,000
Sold joint ventures and other investments		1,487,000
UDR/MetLife
Unconsolidated entities
Number of communities | property	13
Number of apartment homes | home	2,837
Investment in unconsolidated entities	$ 219,387,000		$ 225,195,000
UDR's Ownership Interest	50.20%		50.20%
Income/(loss) from investments	$ (1,846,000)	(1,350,000)
UDR/LaSalle
Unconsolidated entities
Number of communities | property	5
Number of apartment homes | home	1,590
Investment in unconsolidated entities	$ 281,314,000		$ 286,723,000
UDR's Ownership Interest	51%		51%
Income/(loss) from investments	$ (2,878,000)
Preferred Equity Investments
Unconsolidated entities
Number of communities | community	23
Number of apartment homes	5,618
Weighted Average Rate	9.60%
Investment in unconsolidated entities	$ 394,135,000		$ 387,771,000
Income/(loss) from investments	$ 8,163,000	8,635,000
Years to Maturity	3 years 1 month 6 days
UDR Commitment	$ 321,096,000
Number of investments which receive a variable percentage of the value created from the project upon a capital or liquidating event | item	4
Unconsolidated Joint Ventures
Unconsolidated entities
Number of communities | property	18
Number of apartment homes | home	4,427
Investment in unconsolidated entities	$ 500,701,000		511,918,000
Income/(loss) from investments	$ (4,724,000)	(1,350,000)
Variable Interest Entity, Primary Beneficiary
Unconsolidated entities
Number of apartment homes | home	173
Operating Community | Preferred Equity Investments
Unconsolidated entities
Number of communities | community	21
Number of apartment homes	4,545
Weighted Average Rate	9.30%
Investment in unconsolidated entities	$ 308,820,000		304,699,000
Income/(loss) from investments	$ 5,920,000	6,643,000
Years to Maturity	3 years 1 month 6 days
UDR Commitment	$ 252,889,000
Development Community | Preferred Equity Investments
Unconsolidated entities
Number of communities | community	2
Number of apartment homes	1,073
Weighted Average Rate	10.70%
Investment in unconsolidated entities	$ 85,315,000		83,072,000
Income/(loss) from investments	$ 2,243,000	1,992,000
Years to Maturity	3 years 3 months 18 days
UDR Commitment	$ 68,207,000
Development Community | Real estate technology and sustainability investments
Unconsolidated entities
Investment in unconsolidated entities	50,528,000		44,382,000
Income/(loss) from investments	5,646,000	935,000
UDR Commitment	86,000,000
Development Community | Preferred Equity Investments and Real Estate Technology Investments
Unconsolidated entities
Investment in unconsolidated entities	444,663,000		$ 432,153,000
Income/(loss) from investments	$ 13,809,000	$ 9,570,000

JOINT VENTURES AND PARTNERSHI_4

JOINT VENTURES AND PARTNERSHIPS - Commitments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Joint Ventures
Investment in unconsolidated entities	$ 945,364		$ 944,071
Deferred fees from the sale of properties	7,500		7,600
Gain/(loss) on sale of real estate owned	16,867	$ 1
Joint venture management and other fees	$ 1,965	$ 1,242
Type of revenue	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
13th and Market Properties LLC | Accounts Payable, Accrued Expenses and Other Liabilities
Joint Ventures
Investment in unconsolidated entities	$ (8,900)		$ (8,900)

JOINT VENTURES AND PARTNERSHI_5

JOINT VENTURES AND PARTNERSHIPS - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Combined summary of balance sheets relating to unconsolidated joint ventures
Total real estate, net	$ 9,584,085		$ 9,756,029
Investments, at fair value	954,301		952,934
Cash and cash equivalents	2,116	$ 1,172	2,922	$ 1,193
Other assets	195,025		209,969
Total assets	11,190,488		11,373,242
Accounts payable and accrued liabilities	119,739		141,311
Total liabilities	6,333,899		6,420,801
Total equity	3,919,278	3,921,109	3,991,354	$ 4,098,295
Financial information relating to unconsolidated joint ventures operations
Total revenues	413,634	399,549
Property operating expenses	73,478	64,834
Real estate depreciation and amortization	169,858	169,300
Gain/(loss) on sale of real estate owned	16,867	1
Operating income	79,759	66,184
Interest expense	(48,062)	(43,742)
Other income/(loss)	5,865	1,010
Net income/(loss)	46,310	32,925
Unconsolidated Joint Ventures and Partnerships
Combined summary of balance sheets relating to unconsolidated joint ventures
Total real estate, net	3,180,973		3,158,057
Investments, at fair value	304,826		257,832
Cash and cash equivalents	69,247		61,670
Other assets	135,491		146,976
Total assets	3,690,537		3,624,535
Third party debt, net	2,027,146		2,012,816
Accounts payable and accrued liabilities	178,704		171,502
Total liabilities	2,205,850		2,184,318
Total equity	1,484,687		$ 1,440,217
Financial information relating to unconsolidated joint ventures operations
Total revenues	76,256	60,675
Property operating expenses	34,935	28,033
Real estate depreciation and amortization	36,962	24,428
Operating income	4,359	8,214
Interest expense	(24,537)	(23,951)
Other income/(loss)	(1,828)	2,322
Net unrealized/realized gain/(loss) on held investments	27,400	9,789
Net income/(loss)	$ 5,394	$ (3,626)

LEASES - Lessee Future Minimum

LEASES - Lessee Future Minimum Payments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) community	Dec. 31, 2023 USD ($)
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	$ 189,729	$ 190,619
Weighted average remaining lease term	41 years 9 months 18 days	42 years
Weighted average discount rate	5%	5%
Future minimum lease payments
Total operating lease liabilities (discounted)	$ 184,961	$ 185,836
LAND
Future minimum lease payments
2024	9,332
2025	12,442
2026	12,442
2027	12,442
2028	12,442
Thereafter	405,452
Total future minimum lease payments (undiscounted)	464,552
Difference between future undiscounted cash flows and discounted cash flows	(279,591)
Total operating lease liabilities (discounted)	$ 184,961

LEASES - Lessee Expenses (Detai

LEASES - Lessee Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Lease expense:
Variable lease expense	$ 600	$ 700
Operating lease right-of-use asset amortization	900	800
Operating lease liabilities amortization	900	800
Maximum
Lease expense:
Contractual lease expense	100	100
LAND
Lease expense:
Contractual lease expense	3,350	3,292
Variable lease expense	40	28
LAND | Other operating expense
Lease expense:
Total operating lease expense	$ 3,390	$ 3,320

LEASES - Lessor (Details)

LEASES - Lessor (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Future minimum lease payments
Variable lease expense	$ 600	$ 700
Minimum
Lessor leases
Percentage of lease revenue	1%
Maximum
Lessor leases
Percentage of lease revenue	2%
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
2024	$ 19,844
2025	24,675
2026	21,896
2027	18,252
2028	15,464
Thereafter	59,571
Total future minimum lease payments	$ 159,702
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, 2024 USD ($) community	Dec. 31, 2023 USD ($)
Secured debt instruments
Total Debt, net	$ 5,762,328	$ 5,798,709
Long-term Debt	$ 5,772,722
Weighted average interest rate (as a percent)	3.38%
Weighted Average
Secured debt instruments
Years to maturity	5 years 4 months 24 days
Secured Debt
Secured debt instruments
Total Debt, net	$ 1,236,779	1,277,713
Long-term Debt	$ 1,240,019
Weighted average interest rate (as a percent)	3.44%
Number of Communities Encumbered | community	21
Secured Debt | Weighted Average
Secured debt instruments
Years to maturity	4 years 6 months
Unsecured Debt
Secured debt instruments
Total Debt, net	$ 4,525,549	4,520,996
Long-term Debt	$ 4,532,703
Weighted average interest rate (as a percent)	3.36%
Deferred finance costs, net	$ (20,011)	(20,682)
Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	5 years 8 months 12 days
Fixed Rate Debt | Secured Debt
Secured debt instruments
Total Debt, net	$ 1,209,823	1,210,742
Long-term Debt	$ 1,213,019
Weighted average interest rate (as a percent)	3.42%
Number of Communities Encumbered | community	20
Fixed Rate Debt | Secured Debt | Weighted Average
Secured debt instruments
Years to maturity	4 years 4 months 24 days
Variable Rate Debt | Secured Debt
Secured debt instruments
Total Debt, net	$ 26,956	66,971
Long-term Debt	$ 27,000
Weighted average interest rate (as a percent)	4.08%
Number of Communities Encumbered | community	1
Variable Rate Debt | Secured Debt | Weighted Average
Secured debt instruments
Years to maturity	8 years
Mortgages Notes Payable | Fixed Rate Debt | Secured Debt
Secured debt instruments
Deferred financing costs and other non-cash adjustments	$ 3,196	3,009
Long-term Debt	$ 1,213,019	1,213,751
Weighted average interest rate (as a percent)	3.48%
Number of Communities Encumbered | community	20
Mortgages Notes Payable | Fixed Rate Debt | Secured Debt | Weighted Average
Secured debt instruments
Years to maturity	4 years 4 months 24 days
Mortgages Notes Payable | Variable Rate Debt
Secured debt instruments
Stated interest rate	8.31%
Mortgages Notes Payable | Variable Rate Debt | Secured Debt
Secured debt instruments
Long-term Debt		40,017
Tax-exempt notes payable | Variable Rate Debt | Secured Debt
Secured debt instruments
Long-term Debt	$ 27,000	27,000
Weighted average interest rate (as a percent)	4.05%
Number of Communities Encumbered | community	1
Deferred finance costs, net	$ (44)	(46)
Tax-exempt notes payable | Variable Rate Debt | Secured Debt | Weighted Average
Secured debt instruments
Years to maturity	8 years
Unsecured Revolving Credit Facility Due January 2026 | Variable Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	1 year 9 months 18 days
Commercial Paper | Variable Rate Debt | Unsecured Debt
Secured debt instruments
Borrowings outstanding	$ 390,000	408,075
Weighted average interest rate (as a percent)	5.53%
Commercial Paper | Variable Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	1 month 6 days
Working capital credit facility | Variable Rate Debt | Unsecured Debt
Secured debt instruments
Borrowings outstanding	$ 27,059	4,593
Weighted average interest rate (as a percent)	6.21%
Working capital credit facility | Variable Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	9 months 18 days
Term Loan due January 2027 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Long-term Debt	$ 262,500	350,000
Weighted average interest rate (as a percent)	2.68%
Term Loan due January 2027 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	2 years 9 months 18 days
Term Loan due January 2027 | Variable Rate Debt | Unsecured Debt
Secured debt instruments
Long-term Debt	$ 87,500
Weighted average interest rate (as a percent)	6.24%
Term Loan due January 2027 | Variable Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	2 years 9 months 18 days
8.50% Debentures, Due September 2024 | Fixed Rate Debt | Unsecured Debt
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%
8.50% Debentures, Due September 2024 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	6 months
2.95% Medium-Term Note due September 2026 | Fixed Rate Debt | Unsecured Debt
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%
2.95% Medium-Term Note due September 2026 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	2 years 4 months 24 days
3.50 Medium-Term Note due July 2027 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 299,771	$ 299,753
Stated interest rate	3.50%	3.50%
Unamortized discount	$ 229	$ 247
Weighted average interest rate (as a percent)	4.03%
3.50 Medium-Term Note due July 2027 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	3 years 3 months 18 days
3.50% Medium-Term Notes Due January 2028 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 299,550	$ 299,521
Stated interest rate	3.50%	3.50%
Unamortized discount	$ 450	$ 479
Weighted average interest rate (as a percent)	3.50%
3.50% Medium-Term Notes Due January 2028 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	3 years 9 months 18 days
4.40% Medium-Term Notes due January 2029 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 299,997	$ 299,997
Stated interest rate	4.40%	4.40%
Unamortized discount	$ 3	$ 3
Weighted average interest rate (as a percent)	4.27%
4.40% Medium-Term Notes due January 2029 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	4 years 9 months 18 days
3.20% Medium-Term Notes due January 2030 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 607,951	$ 608,294
Stated interest rate	3.20%	3.20%
Unamortized net premium	$ 7,951	$ 8,294
Weighted average interest rate (as a percent)	3.32%
3.20% Medium-Term Notes due January 2030 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	5 years 9 months 18 days
3.00% Medium-Term Notes due August 2031
Secured debt instruments
Long-term Debt	$ 600,000
3.00% Medium-Term Notes due August 2031 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 608,810	$ 609,109
Stated interest rate	3%	3%
Unamortized net premium	$ 8,810	$ 9,109
Weighted average interest rate (as a percent)	3.01%
3.00% Medium-Term Notes due August 2031 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	7 years 4 months 24 days
2.10% Medium Term Note Due August 2032 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 399,706	399,697
Stated interest rate	2.10%
Unamortized discount	$ 294	303
Weighted average interest rate (as a percent)	2.10%
2.10% Medium Term Note Due August 2032 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	8 years 3 months 18 days
1.90% Medium-Term Notes due March 2033 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 348,921	$ 348,890
Stated interest rate	1.90%	1.90%
Unamortized discount	$ 1,079	$ 1,110
Weighted average interest rate (as a percent)	1.90%
1.90% Medium-Term Notes due March 2033 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	9 years
2.10% Medium-Term Note due June 2033 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 299,084	$ 299,059
Stated interest rate	2.10%	2.10%
Unamortized discount	$ 916	$ 941
Weighted average interest rate (as a percent)	2.10%
2.10% Medium-Term Note due June 2033 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	9 years 2 months 12 days
3.10% Medium-Term Notes due November 2034 | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 299,066	$ 299,044
Stated interest rate	3.10%	3.10%
Unamortized discount	$ 934	$ 956
Weighted average interest rate (as a percent)	3.13%
3.10% Medium-Term Notes due November 2034 | Fixed Rate Debt | Unsecured Debt | Weighted Average
Secured debt instruments
Years to maturity	10 years 7 months 6 days
Other [Member] | Fixed Rate Debt | Unsecured Debt
Secured debt instruments
Total Debt, net	$ 1	$ 2

SECURED AND UNSECURED DEBT, N_4

SECURED AND UNSECURED DEBT, NET - Credit Facilities (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($) instrument	Aug. 31, 2021 USD ($) instrument
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	$ 3,800	$ 2,300
Revolving credit facility due 2023 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.755%
Commitment fee	0.15%
Revolving credit facility due 2023 | Unsecured Debt | Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.70%
Commitment fee	0.10%
Revolving credit facility due 2023 | Unsecured Debt | Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.40%
Commitment fee	0.30%
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		2,055
Maximum daily borrowings during the period ended		$ 250,000
Weighted average interest rate during the period ended		5.60%
Term Loan due September 2023 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.83%
basis point subtracted from variable rate for Company receiving green building certifications	0.02%
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%
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			$ 350,000	$ 350,000
Number of interest rate swaps | instrument			5	5
March 2023 until January 2024 | Term Loan Facility Due July 2025 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Borrowings outstanding			$ 350,000	$ 350,000
All-in weighted average interest rate			3.36%	3.36%
January 2024 until July 2024 | Term Loan Facility Due July 2025 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Borrowings outstanding			$ 262,500	$ 262,500
All-in weighted average interest rate			2.68%	2.68%
July 2024 until July 2025 | Term Loan Facility Due July 2025 | Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Borrowings outstanding			$ 175,000	$ 175,000
All-in weighted average interest rate			1.43%	1.43%

SECURED AND UNSECURED DEBT, N_5

SECURED AND UNSECURED DEBT, NET - Working Capital Credit Facility (Details) - Working capital credit facility - Variable Rate Debt - Unsecured Debt - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
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	27,059	4,593
Weighted average daily borrowings during the period ended	13,287	15,829
Maximum daily borrowings during the period ended	$ 39,381	$ 57,107
Weighted average interest rate during the period ended	6.20%	5.90%
Interest rate at end of the period	6.20%	6.30%
Basis points added to to variable rate	0.775%
Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.70%
Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.40%

SECURED AND UNSECURED DEBT, N_6

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, 2024	Dec. 31, 2023
Secured and Unsecured Debt
Total unsecured commercial paper program	$ 700,000	$ 700,000
Borrowings outstanding at end of period	390,000	408,075
Weighted average daily borrowings during the period ended	423,478	384,068
Maximum daily borrowings during the period ended	$ 560,000	$ 505,000
Weighted average interest rate during the period ended	5.60%	5.40%
Interest rate at end of the period	5.50%	5.70%

SECURED AND UNSECURED DEBT, N_7

SECURED AND UNSECURED DEBT, NET - Unsecured Maturities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Aggregate maturities of unsecured debt
2024	$ 502,866
2025	205,382
2026	356,672
2027	656,939
2028	466,526
2029	615,811
2030	830,596
2031	760,930
2032	427,000
2033	650,000
Thereafter	300,000
Subtotal	5,772,722
Non-cash	(10,394)
Total	5,762,328		$ 5,798,709
Interest expense
Aggregate maturities of unsecured debt
Amortization of financing costs	1,200	$ 1,000
Secured Debt
Aggregate maturities of unsecured debt
2024	97,222
2025	178,323
2026	56,672
2027	6,939
2028	166,526
2029	315,811
2030	230,596
2031	160,930
2032	27,000
Subtotal	1,240,019
Non-cash	(3,240)
Total	1,236,779		1,277,713
Secured Debt | Fixed Rate Debt
Aggregate maturities of unsecured debt
2024	97,222
2025	178,323
2026	56,672
2027	6,939
2028	166,526
2029	315,811
2030	230,596
2031	160,930
Subtotal	1,213,019
Non-cash	(3,196)
Total	1,209,823		1,210,742
Secured Debt | Variable Rate Debt
Aggregate maturities of unsecured debt
2032	27,000
Subtotal	27,000
Non-cash	(44)
Total	26,956		66,971
Unsecured Debt
Aggregate maturities of unsecured debt
2024	405,644
2025	27,059
2026	300,000
2027	650,000
2028	300,000
2029	300,000
2030	600,000
2031	600,000
2032	400,000
2033	650,000
Thereafter	300,000
Subtotal	4,532,703
Non-cash	(7,154)
Total	$ 4,525,549		$ 4,520,996

SECURED AND UNSECURED DEBT, N_8

SECURED AND UNSECURED DEBT, NET - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Secured Debt
Percentage of secured debt which encumbers real estate owned based upon book value	13%
Percentage of secured debt of real estate owned which is unencumbered	87%
Long-term Debt	$ 5,762,328		$ 5,798,709
Outstanding balances	5,772,722
3.00% Medium-Term Notes due August 2031
Secured Debt
Outstanding balances	600,000
Interest rate risk	$ 250,000
All-in weighted average interest rate	3.01%
Unsecured Debt
Secured Debt
Long-term Debt	$ 4,525,549		4,520,996
Outstanding balances	4,532,703
Secured Debt
Secured Debt
Long-term Debt	1,236,779		1,277,713
Outstanding balances	$ 1,240,019
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
Outstanding balances	$ 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
Long-term Debt	$ 299,771		$ 299,753
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
Long-term Debt	$ 299,997		$ 299,997
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
Long-term Debt	$ 607,951		$ 608,294
Stated interest rate	3.20%		3.20%
All-in weighted average interest rate	3.32%
Unamortized net premium	$ 7,951		$ 8,294
Fixed Rate Debt | Unsecured Debt | 3.00% Medium-Term Notes due August 2031
Secured Debt
Long-term Debt	$ 608,810		$ 609,109
Stated interest rate	3%		3%
Unamortized net premium	$ 8,810		$ 9,109
Fixed Rate Debt | Unsecured Debt | 2.10% Medium Term Note Due August 2032
Secured Debt
Long-term Debt	$ 399,706		399,697
Stated interest rate	2.10%
Fixed Rate Debt | Unsecured Debt | 2.10% Medium-Term Note due June 2033
Secured Debt
Long-term Debt	$ 299,084		$ 299,059
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
Long-term Debt	$ 348,921		$ 348,890
Stated interest rate	1.90%		1.90%
Fixed Rate Debt | Secured Debt
Secured Debt
Long-term Debt	$ 1,209,823		$ 1,210,742
Outstanding balances	1,213,019
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable
Secured Debt
Outstanding balances	1,213,019		1,213,751
Fixed Rate Debt | Debt Assumed As Part of Acquisition | Mortgages Notes Payable
Secured Debt
Amortization of debt discount (Premium)	400	$ 1,100
Unamortized net premium	1,100		1,500
Variable Rate Debt | Mortgages Notes Payable
Secured Debt
Repayments of outstanding borrowing	$ 40,000
Stated interest rate	8.31%
Variable Rate Debt | Secured Debt
Secured Debt
Long-term Debt	$ 26,956		66,971
Outstanding balances	27,000
Variable Rate Debt | Secured Debt | Mortgages Notes Payable
Secured Debt
Outstanding balances			40,017
Variable Rate Debt | Secured Debt | Tax-exempt notes payable
Secured Debt
Outstanding balances	27,000		$ 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	4.05%

INCOME_(LOSS) PER SHARE (Detail

INCOME/(LOSS) PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Jul. 31, 2021
Antidilutive securities
Net income/(loss)	$ 46,310	$ 32,925
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(3,149)	(1,953)
Net (income)/loss attributable to noncontrolling interests	(12)	(8)
Net income/(loss) attributable to UDR, Inc.	43,149	30,964
Distributions to preferred stockholders - Series E (Convertible)	(1,231)	(1,183)
Net income/(loss) attributable to common stockholders	41,918	29,781
Income/(loss) attributable to common stockholders - diluted	$ 41,918	$ 29,781
Denominator for income/(loss) per share:
Weighted average common shares outstanding	329,244,000	329,165,000
Unvested restricted stock awards	(421,000)	(376,000)
Denominator for basic income/(loss) per share	328,823,000	328,789,000
Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, unvested restricted stock and shares issuable upon settlement of forward sales agreements	131,000	632,000
Denominator for diluted income/(loss) per share	328,954,000	329,421,000
Income/(loss) per weighted average common share - basic	$ 0.13	$ 0.09
Income/(loss) per weighted average common share - diluted	$ 0.13	$ 0.09
Number of shares authorized	450,000,000		450,000,000
OP/DownREIT Units
Denominator for income/(loss) per share:
Antidilutive securities	24,418,000	21,323,000
Convertible Preferred Stock
Denominator for income/(loss) per share:
Antidilutive securities	2,908,000	2,909,000
Unvested LTIP Units and unvested restricted stock
Denominator for income/(loss) per share:
Antidilutive securities	131,000	632,000
ATM
Denominator for income/(loss) per share:
Number of shares authorized				20,000,000
Shares of common stock available for future issuance	14,000,000

NONCONTROLLING INTERESTS (Detai

NONCONTROLLING INTERESTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Noncontrolling interests
Minimum holding period prior to redemption (in years)	1 year
Redeemable noncontrolling interests in the Operating Partnership
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, at beginning of year	$ 961,087
Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(14,629)	$ 67,749
Conversion of OP Units/DownREIT Units to Common Stock or Cash	(7,288)
Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	3,149	1,953
Distributions to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(10,712)
Redeemable Long-Term and Short-Term Incentive Plan Units	5,356
Allocation of other comprehensive income/(loss)	348
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership, at end of year	937,311
Net (income)/loss attributable to noncontrolling interests	(12)	(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
	Mar. 31, 2024	Dec. 31, 2023
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	$ 9,425	$ 10,103
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	937,311	961,087
Transfers between levels of fair value hierarchy	0
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	235,382	228,825
Total assets	246,769	246,138
Debt instruments - fair value
Total liabilities	5,786,655	5,823,923
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	937,311	961,087
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	1,962	7,210
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	9,425	10,103
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	225,512	222,755
Total assets	236,899	240,068
Debt instruments - fair value
Total liabilities	5,167,652	5,215,522
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	937,311	961,087
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	1,962	7,210
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	9,425	10,103
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	1,962	7,210
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	1,962	7,210
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	9,425	10,103
Debt instruments - fair value
Redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	937,311	961,087
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	9,425	10,103
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	225,512	222,755
Total assets	225,512	222,755
Debt instruments - fair value
Total liabilities	5,167,652	5,215,522
Unsecured Debt | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	4,128,501	4,129,010
Unsecured Debt | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	3,603,760	3,611,697
Unsecured Debt | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	3,603,760	3,611,697
Unsecured Debt | Working capital credit facility | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	27,059	4,593
Unsecured Debt | Working capital credit facility | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	27,059	4,593
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	27,059	4,593
Unsecured Debt | Commercial Paper | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	390,000	408,075
Unsecured Debt | Commercial Paper | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	390,000	408,075
Unsecured Debt | Commercial Paper | Estimate of Fair Value, Fair Value Disclosure | Level 3 | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	390,000	408,075
Fixed Rate Debt | Secured Debt | Mortgages Notes Payable | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value	1,214,095	1,215,228
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	1,119,833	1,124,140
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	1,119,833	1,124,140
Variable Rate Debt | Secured Debt | Mortgages Notes Payable | Carrying (Reported) Amount, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value		40,017
Variable Rate Debt | Secured Debt | Mortgages Notes Payable | Estimate of Fair Value, Fair Value Disclosure | Fair Value, Measurements, Recurring
Debt instruments - fair value
Fair value		40,017
Variable 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		40,017
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	Mar. 31, 2024 USD ($) instrument
Derivatives
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	$ 6,200
Designated as Hedging Instrument | Interest rate swap and caps
Derivatives
Number instruments | instrument	4
Notional	$ 282,380
Designated as Hedging Instrument | Treasury lock arrangement
Derivatives
Notional	150,000
Deferred gain recorded in accumulated other comprehensive income/(loss)	5,000
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, 2024	Dec. 31, 2023
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheets
Derivative Asset Designated as Hedging Instrument, Fair Value	$ 9,425	$ 10,103
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	$ 9,425	$ 10,103

DERIVATIVES AND HEDGING ACTIV_5

DERIVATIVES AND HEDGING ACTIVITY - Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Effect of derivative instruments on the Consolidated Statements of Operations
Unrealized holding gain/(loss)	$ 6,664	$ (273)
Gain/(Loss) Reclassified from Accumulated OCI in Interest expense	1,995	1,369
Interest rate contracts | Interest expense | Cash Flow Hedging
Effect of derivative instruments on the Consolidated Statements of Operations
Unrealized holding gain/(loss)	6,664	(273)
Gain/(Loss) Reclassified from Accumulated OCI in Interest expense	$ 1,995	$ 1,369

DERIVATIVES AND HEDGING ACTIV_6

DERIVATIVES AND HEDGING ACTIVITY - Effectiveness (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivatives and hedging activity
Total amount of Interest expense presented on the Consolidated Statements of Operations	$ 48,062	$ 43,742

DERIVATIVES AND HEDGING ACTIV_7

DERIVATIVES AND HEDGING ACTIVITY - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Offsetting derivative assets
Gross Amounts of Recognized Assets	$ 9,425	$ 10,103
Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)	$ 9,425	$ 10,103
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets.	Other Assets.
Net Amount	$ 9,425	$ 10,103

STOCK BASED COMPENSATION (Detai

STOCK BASED COMPENSATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
General and administrative expense
Stock based compensation
Stock based compensation expense	$ 7.3	$ 8.2

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Mar. 31, 2024 USD ($) community
Real estate properties
Number of communities | community	168
Costs Incurred to Date	$ 234,723
UDR's Remaining Commitment	170,224
Real estate technology investments
Real estate properties
Costs Incurred to Date	57,140
UDR's Remaining Commitment	$ 48,860
Wholly owned - under development
Real estate properties
Number of communities | community	1
Costs Incurred to Date	$ 126,163
UDR's Remaining Commitment	$ 7,837
Wholly owned - redevelopment
Real estate properties
Number of communities | community	10
Costs Incurred to Date	$ 51,420
UDR's Remaining Commitment	$ 113,527

REPORTABLE SEGMENTS (Details)

REPORTABLE SEGMENTS (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) segment home	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Segments
Same store communities | home	51,802
Reportable Segments
Management fee (as a percent)	3.25%
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	$ 411,669	$ 398,307
Reconciling items:
Joint venture management and other fees	$ 1,965	$ 1,242
Type of revenue	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
Property management	$ (13,379)	$ (12,945)
Other operating expenses	(6,828)	(3,032)
Real estate depreciation and amortization	(169,858)	(169,300)
General and administrative	(17,810)	(17,480)
Casualty-related (charges)/recoveries, net	(6,278)	(4,156)
Other depreciation and amortization	(4,316)	(3,649)
Gain/(loss) on sale of real estate owned	16,867	1
Income/(loss) from unconsolidated entities	9,085	9,707
Interest expense	(48,062)	(43,742)
Interest income and other income/(expense), net	5,865	1,010
Tax (provision)/benefit, net	(337)	(234)
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(3,149)	(1,953)
Net (income)/loss attributable to noncontrolling interests	(12)	(8)
Net income/(loss) attributable to UDR, Inc.	43,149	30,964
Reportable apartment home segment assets:
Total segment assets	15,991,196		$ 16,023,859
Accumulated depreciation	(6,407,111)		(6,267,830)
Total real estate owned, net of accumulated depreciation	9,584,085		9,756,029
Reconciling items:
Cash and cash equivalents	2,116	1,172	2,922	$ 1,193
Restricted cash	29,850	28,038	31,944	$ 29,001
Notes receivable, net	235,382		228,825
Investment in and advances to unconsolidated joint ventures, net	954,301		952,934
Operating lease right-of-use assets	189,729		190,619
Other assets	195,025		209,969
Total consolidated assets	11,190,488		11,373,242
Total Communities
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations
Lease revenue	399,179	387,017
Other revenue	12,490	11,290
Rental income	411,669	398,307
Reportable apartment home segment NOI	279,396	275,503
Same Communities | 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	117,899	114,289
Other revenue	2,974	2,783
Rental income	120,873	117,072
Reportable apartment home segment NOI	89,413	88,369
Reportable apartment home segment assets:
Total segment assets	4,376,985		4,366,038
Same Communities | 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	76,811	74,122
Other revenue	3,124	2,472
Rental income	79,935	76,594
Reportable apartment home segment NOI	54,705	53,441
Reportable apartment home segment assets:
Total segment assets	3,214,861		3,205,036
Same Communities | 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	80,330	77,342
Other revenue	1,735	1,742
Rental income	82,065	79,084
Reportable apartment home segment NOI	52,634	52,398
Reportable apartment home segment assets:
Total segment assets	3,899,854		3,890,762
Same Communities | 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	56,784	55,799
Other revenue	2,414	2,133
Rental income	59,198	57,932
Reportable apartment home segment NOI	40,275	39,785
Reportable apartment home segment assets:
Total segment assets	1,599,068		1,589,605
Same Communities | 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	37,615	37,678
Other revenue	1,566	1,379
Rental income	39,181	39,057
Reportable apartment home segment NOI	24,791	24,600
Reportable apartment home segment assets:
Total segment assets	1,334,198		1,330,063
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	29,740	27,787
Other revenue	677	781
Rental income	30,417	28,568
Reportable apartment home segment NOI	17,578	$ 16,910
Reportable apartment home segment assets:
Total segment assets	$ 1,566,230		$ 1,642,355

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 43,149	$ 30,964

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false