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Income from Participating Loan

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Number of apartment homes acquired.

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The number of investments which receive a variable percentage of the value created from the project upon a capital or liquidating event.

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The number of preferred equity agreements the company redeemed during the period.

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Participating Loan, Interest Rate, Stated Percentage

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of the entity's equity method investment which has been sold.

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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The number of real estate properties owned as of the balance sheet date.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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JOINT VENTURES AND PARTNERSHIPS - Summary (Details) $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	Apr. 30, 2026 home	Feb. 28, 2026 USD ($) item	Mar. 31, 2026 USD ($) community property home item	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
JOINT VENTURES AND PARTNERSHIPS
Number Properties \| community			161
Investment in unconsolidated entities			$ 750,459		$ 879,735
Sold joint ventures and other investments - Investment					136,234
Income/(loss) from investments			19,696	$ 5,814
Equity method investment amount sold					$ 136,234
Sold unconsolidated joint ventures and partnerships			$ 2,977	3,742
Number of preferred equity agreements redeemed \| item			2
UDR/MetLife
JOINT VENTURES AND PARTNERSHIPS
Number Properties \| property			13
Number of apartment homes \| home			2,837
UDR's ownership interest			50.20%		50.20%
Investment in unconsolidated entities			$ 183,280		$ 189,420
Income/(loss) from investments			$ (1,213)	(1,041)
UDR/LaSalle
JOINT VENTURES AND PARTNERSHIPS
Number Properties \| property			9
Number of apartment homes \| home			2,564
UDR's ownership interest			51.00%		51.00%
Investment in unconsolidated entities			$ 235,936		$ 242,337
Income/(loss) from investments			$ (3,269)	(1,035)
Preferred Equity Investments
JOINT VENTURES AND PARTNERSHIPS
Number of investments which receive a variable percentage of the value created from the project upon a capital or liquidating event \| item			2
Aggregate proceeds		$ 138,900
Number of preferred equity agreements redeemed \| item		2
Unconsolidated Joint Ventures
JOINT VENTURES AND PARTNERSHIPS
Number Properties \| property			22
Number of apartment homes \| home			5,401
Investment in unconsolidated entities			$ 419,216		431,757
Income/(loss) from investments			(4,482)	(2,076)
Real estate technology and sustainability investments
JOINT VENTURES AND PARTNERSHIPS
UDR Commitment			86,000
Investment in unconsolidated entities			92,533		74,747
Income/(loss) from investments			$ 17,032	1,669
Operating Community \| Preferred Equity Investments
JOINT VENTURES AND PARTNERSHIPS
Number Properties \| community			10
Number of apartment homes \| home			3,617
Weighted Average Rate			10.50%
UDR Commitment			$ 222,537
Investment in unconsolidated entities			238,710		236,997
Income/(loss) from investments			4,169	2,479
Debt and Preferred Equity Program \| Real estate technology and sustainability investments
JOINT VENTURES AND PARTNERSHIPS
Investment in unconsolidated entities			331,243		$ 311,744
Income/(loss) from investments			$ 21,201	$ 4,148
Operating community in Portland, Oregon \| Subsequent Event
JOINT VENTURES AND PARTNERSHIPS
Number of apartment homes acquired \| home	232