UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

Form 10-Q

Commission file number 1-10524

United Dominion Realty Trust, Inc.

(Exact name of registrant as specified in its charter)

1745 Shea Center Drive, Suite 200,

Highlands Ranch, Colorado 80129

(Address of principal executive offices) (zip code)

(720) 283-6120

(Registrant’s telephone number, including area code)

     Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes þ          No o

      Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act).     Yes þ          No o

      Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).     Yes o          No þ

      The number of shares of the issuer’s common stock, $0.01 par value, outstanding as of November 3, 2005 was 137,184,739.

UNITED DOMINION REALTY TRUST, INC.

FORM 10-Q

INDEX

PART I — FINANCIAL INFORMATION

UNITED DOMINION REALTY TRUST, INC.

CONSOLIDATED BALANCE SHEETS

(In thousands, except for share data)

(Unaudited)

See accompanying notes to consolidated financial statements.

UNITED DOMINION REALTY TRUST, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share data)

(Unaudited)

See accompanying notes to consolidated financial statements.

UNITED DOMINION REALTY TRUST, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands, except for share data)

(Unaudited)

See accompanying notes to consolidated financial statements.

UNITED DOMINION REALTY TRUST, INC.

CONSOLIDATED STATEMENT OF STOCKHOLDERS’ EQUITY

(In thousands, except share data)

(Unaudited)

See accompanying notes to consolidated financial statements.

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

SEPTEMBER 30, 2005

(UNAUDITED)

      United Dominion Realty Trust, Inc. is a self-administered real estate investment trust, or REIT, that owns, acquires, renovates, develops, and manages middle-market apartment communities nationwide. The accompanying consolidated financial statements include the accounts of United Dominion and its subsidiaries, including United Dominion Realty, L.P. (the “Operating Partnership”), and Heritage Communities L.P. (the “Heritage OP”) (collectively, “United Dominion”). As of September 30, 2005, there were 166,061,749 units in the Operating Partnership outstanding, of which 156,118,178 units or 94.0% were owned by United Dominion and 9,943,571 units or 6.0% were owned by limited partners (of which 1,791,329 are owned by the holders of the Series A OPPS, see Note 6). As of September 30, 2005, there were 5,542,200 units in the Heritage OP outstanding, of which 5,201,355 units or 93.9% were owned by United Dominion and 340,845 units or 6.1% were owned by limited partners. The consolidated financial statements of United Dominion include the minority interests of the unitholders in the Operating Partnership and the Heritage OP. All significant intercompany accounts and transactions have been eliminated in consolidation.

      The accompanying interim unaudited consolidated financial statements have been prepared according to the rules and regulations of the Securities and Exchange Commission. Certain information and footnote 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. The accompanying consolidated financial statements should be read in conjunction with the audited financial statements and related notes appearing in United Dominion’s Annual Report on Form 10-K for the year ended December 31, 2004, filed with the Securities and Exchange Commission as updated by the Current Report on Form 8-K filed August 11, 2005.

      In the opinion of management, the consolidated financial statements reflect all adjustments which are necessary for the fair presentation of financial position at September 30, 2005 and results of operations for the interim periods ended September 30, 2005 and 2004. 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 preparation of these financial statements 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 financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates. Certain previously reported amounts have been reclassified to conform to the current financial statement presentation.

      United Dominion adopted the fair-value-based method of accounting for share-based payments effective January 1, 2004 using the prospective method described in FASB Statement No. 148, “Accounting for Stock-Based Compensation — Transition and Disclosure.” Currently, United Dominion uses the Black-Scholes-Merton formula to estimate the value of stock options granted to employees and expects to continue to use this acceptable option valuation model upon the required adoption of Statement 123(R) on January 1, 2006. Because Statement 123(R) must be applied not only to new awards but to previously granted awards that are not fully vested on the effective date, and because United Dominion adopted Statement 123 using the prospective transition method (which applied only to awards granted, modified or settled after the adoption date), compensation cost for some previously granted awards that were not recognized under Statement 123 will be recognized under Statement 123(R).

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

      In June 2005, the FASB ratified its consensus in EITF Issue 04-05, “Determining Whether a General Partner, or the General Partners as a Group, Controls a Limited Partnership or Similar Entity When the Limited Partners Have Certain Rights” (Issue 04-05). The effective date for Issue 04-05 is June 29, 2005 for all new or modified partnerships and January 1, 2006 for our remaining partnerships for the applicable provisions. The adoption of the provisions of EITF 04-05 is not anticipated to have a material impact on our financial position or results of operations.

      At September 30, 2005, there are 253 communities with 74,215 apartment homes classified as real estate held for investment. The following table summarizes the components of real estate held for investment (dollars in thousands):

      FASB Statement No. 144, “Accounting for the Impairment or Disposal of Long-Lived Assets” (FAS 144) requires, among other things, that the primary assets and liabilities and the results of operations of United Dominion’s real properties which have been sold subsequent to January 1, 2002, or are held for disposition subsequent to January 1, 2002, be classified as discontinued operations and segregated in United Dominion’s Consolidated Statements of Operations and Balance Sheets. Properties classified as real estate held for disposition generally represent properties that are under contract for sale and are expected to close within the next twelve months.

      For purposes of these financial statements, FAS 144 results in the presentation of the primary assets and liabilities and the net operating results of those properties sold or classified as held for disposition through September 30, 2005, as discontinued operations for all periods presented. The adoption of FAS 144 does not have an impact on net income available to common stockholders. FAS 144 only results in the reclassification of the operating results of all properties sold or classified as held for disposition through September 30, 2005, within the Consolidated Statements of Operations for the three and nine months ended September 30, 2005 and 2004, and the reclassification of the assets and liabilities within the Consolidated Balance Sheets for 2005 and 2004.

      For the nine months ended September 30, 2005, United Dominion sold 21 communities with 6,002 apartment homes, 102 condominiums from three communities with a total of 313 condominiums, and one parcel of land. We recognized gains for financial reporting purposes of $66.7 million on these sales. At September 30, 2005, United Dominion had one community with a total of 350 apartment homes and a net book value of $23.1 million, two communities with a total of 187 condominiums and a net book value of $23.5 million, and two parcels of land with a net book value of $5.1 million included in real estate held for disposition. In conjunction with the sale of ten communities in July 2005, we received short-term notes for $124.7 million that bear interest at 6.75% and have maturities ranging from September 2005 to July 2006. As of

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

September 30, 2005, the balance on the notes receivable was $90.9 million. We recognized gains for financial reporting purposes of $6.9 million and will recognize $14.7 million in additional gains as the notes receivable mature. For the year ended December 31, 2004, United Dominion sold 19 communities with a total of 5,425 apartment homes, 24 condominiums from a community of 36 condominiums, and one parcel of land. The results of operations for these properties and the interest expense associated with the secured debt on these properties are classified on the Consolidated Statements of Operations in the line item titled “Income from discontinued operations, net of minority interests.”

      United Dominion has elected Taxable REIT Subsidiary (“TRS”) status for certain of its corporate subsidiaries, primarily those engaged in condominium conversion and sale activities. United Dominion recognized a provision for income taxes of $2.4 million and $3.8 million for the three and nine months ended September 30, 2005, respectively. These amounts were classified as reductions of the net gain on sale of depreciable property in the accompanying consolidated statement of operations.

      The following is a summary of income from discontinued operations for the periods presented, (dollars in thousands):

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

      Secured debt on continuing and discontinued operations, which encumbers $1.9 billion or 35% of United Dominion’s real estate owned based upon book value ($3.5 billion or 65% of United Dominion’s real estate owned is unencumbered) consists of the following as of September 30, 2005 (dollars in thousands):

      During the second quarter of 2005, we elected to convert a $75 million variable rate debt placement to a fixed rate of 4.86%. The rate, currently at 4.33%, will float until December 1, 2005 and then convert to a 7-year fixed rate of 4.86%.

      Approximate principal payments due during each of the next five calendar years and thereafter, as of September 30, 2005, are as follows (dollars in thousands):

      During the first quarter of 2005, we prepaid approximately $110 million of secured debt. In conjunction with these prepayments, we incurred prepayment penalties of $8.5 million in both continuing and discontinued operations as “Loss on early debt retirement.” These penalties were funded by the proceeds from the sale of our technology investment of $12.3 million.

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

      A summary of unsecured debt as of September 30, 2005 and December 31, 2004 is as follows (dollars in thousands):

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

      Basic earnings per common share is computed based upon the weighted average number of common shares outstanding during the period. Diluted earnings per common share is computed based upon common shares outstanding plus the effect of dilutive stock options and other potentially dilutive common stock equivalents. The dilutive effect of stock options and other potentially dilutive common stock equivalents is determined using the treasury stock method based on United Dominion’s average stock price.

      The following table sets forth the computation of basic and diluted earnings per share for the periods presented, (dollars in thousands, except per share data):

      The effect of the conversion of the operating partnership units, Series A Out-Performance Partnership Shares, and convertible preferred stock is not dilutive and is therefore not included in the above calculations. If the operating partnership units were converted to common stock, the additional shares of common stock outstanding for the three and nine months ended September 30, 2005 would be 8,503,993 and 8,509,748 weighted average common shares, and 8,677,459 and 8,681,292 weighted average common shares for the three and nine months ended September 30, 2004. If the Series A Out-Performance Partnership Shares were converted to common stock, the additional shares of common stock outstanding for the three and nine months ended September 30, 2005 and 2004 would be 1,791,329 weighted average common shares. If the convertible preferred stock were converted to common stock, the additional shares of common stock outstanding for the three and nine months ended September 30, 2005 would be 2,803,812 weighted average common shares, and 6,502,140 weighted average common shares for the three and nine months ended September 30, 2004, respectively.

      Total comprehensive income for the three and nine months ended September 30, 2005 and 2004, was $15.1 million and $82.5 million for 2005 and $27.8 million and $73.5 million for 2004, respectively. The

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

difference between net income and total comprehensive income is primarily due to the fair value accounting for interest rate swaps in 2004.

Commitments

      United Dominion is committed to completing its real estate under development, which has an estimated cost to complete of $64.2 million at September 30, 2005.

Contingencies

      In May 2003, the stockholders of United Dominion approved the Series B Out-Performance Program (the “Series B Program”) pursuant to which certain executive officers of United Dominion (the “Series B Participants”) were given the opportunity to invest indirectly in United Dominion by purchasing interests in a limited liability company (the “Series B LLC”), the only asset of which is a special class of partnership units of United Dominion Realty, L.P. (“Series B OPPSs”). The purchase price for the Series B OPPSs was determined by United Dominion’s board of directors to be $1 million, assuming 100% participation, and was based upon the advice of an independent valuation expert. The Series B Program measured the cumulative total return on our common stock over the 24-month period from June 1, 2003 to May 31, 2005.

      The Series B Program was designed to provide participants with the possibility of substantial returns on their investment if the total cumulative return on United Dominion’s common stock, as measured by the cumulative amount of dividends paid plus share price appreciation during the measurement period (a) exceeded the cumulative total return of the Morgan Stanley REIT Index peer group index over the same period; and (b) was at least the equivalent of a 22% total return, or 11% annualized.

      At the conclusion of the measurement period on May 31, 2005, the total cumulative return on our common stock over the 24-month period did not satisfy these criteria, and therefore, the Series B LLC as holder of the Series B OPPSs did not receive (for the indirect benefit of the Series B Participants as holders of interests in the Series B LLC) distributions and allocations of income and loss from United Dominion Realty, L.P. (accounted for on a consistent basis with all other OP Units) equal to the distributions and allocations that would be received on the number of OP Units. As a result, the investment made by the holders of the Series B OPPSs was forfeited.

      In May 2005, the stockholders of United Dominion approved the Series C Out-Performance Program (the “Series C Program”) pursuant to which certain executive officers and other key employees of United Dominion (the “Series C Participants”) were given the opportunity to invest indirectly in United Dominion by purchasing interests in UDR Out-Performance III, LLC, a Delaware limited liability company (the “Series C LLC”), the only asset of which is a special class of partnership units of United Dominion Realty, L.P. (“Series C OPPSs”). The purchase price for the Series C OPPSs was determined by the Compensation Committee of United Dominion’s board of directors to be $750,000, assuming 100% participation, and was based upon the advice of an independent valuation expert. The Series C Program will measure the cumulative total return on our common stock over the 36-month period from June 1, 2005 to May 30, 2008.

      The Series C Program is designed to provide participants with the possibility of substantial returns on their investment if the total cumulative return on United Dominion’s common stock, as measured by the

UNITED DOMINION REALTY TRUST, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)

cumulative amount of dividends paid plus share price appreciation during the measurement period is at least the equivalent of a 36% total return, or 12% annualized (“Minimum Return”).

      At the conclusion of the measurement period, if the total cumulative return on our common stock satisfies these criteria, the Series C LLC as holder of the Series C OPPSs will receive (for the indirect benefit of the Series C Participants as holders of interests in the Series C LLC) distributions and allocations of income and loss from United Dominion Realty, L.P. equal to the distributions and allocations that would be received on the number of OP Units obtained by:

      If, on the valuation date, the cumulative total return of United Dominion’s common stock does not meet the Minimum Return, then the Series C Participants will forfeit their entire initial investment.

Litigation and Legal Matters

      United Dominion is subject to various legal proceedings and claims arising in the ordinary course of business. United Dominion cannot determine the ultimate liability with respect to such legal proceedings and claims at this time. United Dominion 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 flow.

      For the period from October 22, 2005 to November 3, 2005, we have repurchased 627,500 shares of our common stock under our stock repurchase program at an average share price of $21.62.

Forward-Looking Statements

      This Report contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Such forward-looking statements include, without limitation, statements concerning property acquisitions and dispositions, development activity and capital expenditures, capital raising activities, rent growth, occupancy, and rental expense growth. Words such as “expects,” “anticipates,” “intends,” “plans,” “believes,” “seeks,” “estimates,” and variations of such words and similar expressions are intended to identify such forward-looking statements. Such statements involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of United Dominion to be materially different from the results of operations or plans expressed or implied by such forward-looking statements. Such factors include, among other things, unanticipated adverse business developments affecting us or our properties, adverse changes in the real estate markets and general and local economies and business conditions. Although we believe that the assumptions underlying the forward-looking statements contained herein are reasonable, any of the assumptions could be inaccurate, and therefore such statements included in this Report may not prove to be accurate. In light of the significant uncertainties inherent in the forward-looking statements included herein, the inclusion of such information should not be regarded as a representation by us or any other person that the results or conditions described in such statements or our objectives and plans will be achieved.

Business Overview

      We are a real estate investment trust, or REIT, that owns, acquires, renovates, develops, and manages middle-market apartment communities nationwide. We were formed in 1972 as a Virginia corporation. In June 2003, we changed our state of incorporation from Virginia to Maryland. Our subsidiaries include two operating partnerships, Heritage Communities L.P., a Delaware limited partnership, and United Dominion Realty, L.P., a Delaware limited partnership. Unless the context otherwise requires, all references in this Report to “we,” “us,” “our,” “the company,” or “United Dominion” refer collectively to United Dominion Realty Trust, Inc. and its subsidiaries.

      At September 30, 2005, our portfolio included 256 communities with 74,752 apartment homes nationwide. The following table summarizes our market information by major geographic markets (includes real estate held for disposition, real estate under development, and land, but excludes commercial properties):

Liquidity and Capital Resources

      Liquidity is the ability to meet present and future financial obligations either through operating cash flows, the sale or maturity of existing assets, or by the acquisition of additional funds through capital management. Both the coordination of asset and liability maturities and effective capital management are important to the maintenance of liquidity. Our primary source of liquidity is our cash flow from operations as determined by rental rates, occupancy levels, and operating expenses related to our portfolio of apartment homes. We routinely use our unsecured bank credit facility to temporarily fund certain investing and financing activities prior to arranging for longer-term financing. During the past several years, proceeds from the sale of real estate have been used for both investing and financing activities.

      We expect to meet our short-term liquidity requirements generally through net cash provided by operations and borrowings under credit arrangements. We expect to meet certain long-term liquidity requirements such as scheduled debt maturities, the repayment of financing on development activities, and potential property acquisitions, through long-term secured and unsecured borrowings, the disposition of properties, the disposition of condominiums, and the issuance of additional debt or equity securities. We believe that our net cash provided by operations will continue to be adequate to meet both operating requirements and the payment of dividends by the company in accordance with REIT requirements in both the short- and long-term. Likewise, the budgeted expenditures for improvements and renovations of certain properties are expected to be funded from property operations.

      We have a shelf registration statement filed with the Securities and Exchange Commission which provides for the issuance of up to an aggregate of $1.5 billion in common shares, preferred shares, and debt securities to facilitate future financing activities in the public capital markets. During the third quarter of 2005, we completed one financing activity under our $1.5 billion shelf registration statement. This activity is summarized in the section titled “Financing Activities” below. As of September 30, 2005, approximately $0.9 billion of equity and debt securities remained available for use under the shelf registration statement. Access to capital markets is dependent on market conditions at the time of issuance.

      In October 2004, we filed a prospectus supplement under the Securities Act of 1933 relating to the offering of up to 5 million shares of our common stock that we may issue and sell through an agent from time to time in “at the market offerings,” as defined in Rule 415 of the Securities Act of 1933. Any sales of these shares will be made under our $1.5 billion shelf registration statement pursuant to a sales agreement that we entered into with the agent in July 2003. The sales price of the common stock that may be sold under the sales agreement will be no lower than the minimum price designated by us prior to the sale. During the fourth quarter of 2004, we sold a total of 472,000 shares of common stock pursuant to the sales agreement at a weighted average sales price of $20.36, for net proceeds to us of approximately $9.4 million. We did not sell any shares of common stock under the sales agreement during the nine months ended September 30, 2005.

Future Capital Needs

      Future development expenditures are expected to be funded with proceeds from the sale of property, with construction loans, through joint ventures and, to a lesser extent, with cash flows provided by operating activities. Acquisition activity in strategic markets is expected to be largely financed through the issuance of equity and debt securities, the issuance of operating partnership units, the assumption or placement of secured and/or unsecured debt, and by the reinvestment of proceeds from the sale of properties.

      During the remainder of 2005, we have approximately $1.5 million of secured debt and $49.9 million of unsecured debt maturing and we anticipate repaying that debt with proceeds from borrowings under our secured or unsecured credit facilities, or the issuance of new unsecured debt securities or equity.

Critical Accounting Policies and Estimates

      Our critical accounting policies are those having the most impact on the reporting of our financial condition and results and those requiring significant judgments and estimates. These policies include those related to (1) capital expenditures, (2) impairment of long-lived assets, and (3) real estate investment properties. Our critical accounting policies are described in more detail in the section entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the year ended December 31, 2004. There have been no significant changes in our critical accounting policies from those reported in our 2004 Annual Report on Form 10-K. With respect to these critical accounting policies, management believes that the application of judgments and assessments is consistently applied and produces financial information that fairly depicts the results of operations for all periods presented.

Statements of Cash Flow

      The following discussion explains the changes in net cash provided by operating and financing activities and net cash used in investing activities that are presented in our Consolidated Statements of Cash Flows.

      For the nine months ended September 30, 2005, our cash flow provided by operating activities was $170.5 million compared to $173.9 million for the same period in 2004. The slight decrease in cash flow

from operating activities resulted primarily from a $31.4 million increase in interest expense and a $1.6 million net increase in operating assets/liabilities for the period that was offset by a $30.0 million increase in property operating income from our apartment community portfolio (see discussion under “Apartment Community Operations”).

      For the nine months ended September 30, 2005, net cash used in investing activities was $177.8 million compared to $318.7 million for the same period in 2004. Changes in the level of investing activities from period to period reflects our strategy as it relates to our acquisition, capital expenditure, development, and disposition programs, as well as the impact of the capital market environment on these activities, all of which are discussed in further detail below.

      During the nine months ended September 30, 2005, we acquired five apartment communities with 2,021 apartment homes and one parcel of land. Our long-term strategic plan is to achieve greater operating efficiencies by investing in fewer, more concentrated markets. As a result, we have been expanding our interests in the fast growing Southern California, Florida, and Metropolitan DC markets over the past two years. During 2005, we plan to continue to channel new investments into those markets we believe will provide the best investment returns. Markets will be targeted based upon defined criteria including past performance, expected job growth, current and anticipated housing supply and demand, and the ability to attract and support household formation.

      In conformity with accounting principles generally accepted in the United States, we capitalize those expenditures related to acquiring new assets, materially enhancing the value of an existing asset, or substantially extending the useful life of an existing asset. Expenditures necessary to maintain an existing property in ordinary operating condition are expensed as incurred.

      During the first nine months of 2005, we spent $96.9 million or $1,270 per home on capital expenditures for all of our communities, excluding development and commercial properties. These capital improvements included turnover related expenditures for floor coverings and appliances, other recurring capital expenditures such as HVAC equipment, roofs, siding, parking lots, and other non-revenue enhancing capital expenditures, which aggregated $29.3 million or $383 per home. In addition, revenue enhancing capital expenditures, kitchen and bath upgrades, and other extensive interior upgrades totaled $56.3 million or $739 per home and major renovations totaled $11.3 million or $148 per home for the nine months ended September 30, 2005.

      The following table outlines capital expenditures and repair and maintenance costs for all of our communities, excluding real estate under development and commercial properties for the periods presented: