UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-K/A

(Amendment No. 1)

ANNUAL REPORT PURSUANT TO SECTIONS 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

(Mark One)

For the fiscal year ended December 31, 2012

OR

Commission File No. 1-14306

BRE PROPERTIES, INC.

(Exact name of registrant as specified in its charter)

(415) 445-6530

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    x  Yes    ¨  No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    ¨  Yes    x  No

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.    x  Yes    ¨  No

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    x  Yes    ¨  No

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.    x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

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

At June 30, 2012, the aggregate market value of the registrant’s shares of Common Stock, par value $.01 per share, held by non-affiliates of the registrant was approximately $3,841,000,000. At January 31, 2013, 76,940,017 shares of Common Stock were outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Proxy Statement for the Annual Meeting of Shareholders of BRE Properties, Inc. to be filed within 120 days of December 31, 2012 are incorporated by reference in Part III of this report.

EXPLANATORY NOTE

The sole purpose of this Amendment on Form 10-K/A (the “Amendment”) to the Annual Report on Form 10-K of BRE Properties, Inc. for the fiscal year ended December 31, 2012 (the “Form 10-K”) is to amend Exhibits 32.1 and 32.2 to reference the certification of the Form 10-K for the year ended December 31, 2012. In addition, pursuant to Rule 12b-15 under the Securities Exchange Act of 1934, as amended, the Amendment includes new certifications of our principal executive officer and principal financial officer on Exhibits 31.1 and 31.2, each as of the filing date of the Amendment.

No other changes have been made to the Form 10-K. This Amendment does not reflect any subsequent events occurring after the original filing date of the Form 10-K or modify or update in any way disclosures made in the original filings.

PART IV

(a) The following documents are filed as a part of this report:

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated: February 20, 2013

INDEX TO EXHIBITS