UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d)

of The Securities Exchange Act of 1934

May 2, 2013

Date of Report (Date of earliest event reported)

CAPITAL ONE FINANCIAL CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (703) 720-1000

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

(a) The 2013 Annual Stockholder Meeting of Capital One Financial Corporation (the “Company”) was held on May 2, 2013. On March 7, 2013, the record date for the meeting, 583,904,059 shares of the Company’s common stock were issued and outstanding, of which 502,048,005 were present at the meeting for purposes of establishing a quorum.

(b) Stockholders voted on the following matters:

(1) Stockholders elected Mr. Richard D. Fairbank, Mr. Lewis Hay, III, Mr. Benjamin P. Jenkins, III, Mr. Peter E. Raskind, Mr. Mayo A. Shattuck III, Mr. Bradford H. Warner and Ms. Catherine G. West to the Board of Directors for terms expiring at the 2014 annual meeting of stockholders;

(2) Stockholders ratified the selection of the firm Ernst & Young LLP to serve as the independent registered public accounting firm of the Company for 2013;

(3) Stockholders approved, on an advisory basis, the Company’s 2012 named executive officer compensation; and

(4) Stockholders did not approve by the necessary vote amendments to the Company’s Restated Certificate of Incorporation to remove supermajority voting standards applicable to the following actions:

(a) Future amendments to the Amended and Restated Bylaws and Restated Certificate of Incorporation;

(b) Removing any director from office; and

(c) Certain business combinations.

As described in the proxy statement for the meeting, each of the proposals to approve amendments to the Company’s Restated Certificate of Incorporation required approval of at least 467,123,248 shares, representing 80% of the Company’s common stock outstanding.

Set forth below are the number of votes cast for or against each such matter as well as the number of abstentions and broker non-votes with respect to each such matter.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Company has duly caused this Current Report on Form 8-K to be signed on its behalf by the undersigned hereunto duly authorized.

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