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 1, 2014

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):

As described under Item 5.07 of this Current Report on Form 8-K, on May 1, 2014, at the 2014 Annual Stockholder Meeting (the “Annual Meeting”) of Capital One Financial Corporation (the “Company”), the Company’s stockholders, upon the recommendation of the Company’s Board of Directors (the “Board”), approved amendments to the Company’s Restated Certificate of Incorporation (the “Certificate”) that remove certain of the supermajority voting requirements in the Certificate and replace them with majority voting standards. The amendments became effective upon the Company filing a Certificate of Amendment (the “Certificate of Amendment”) with the Office of the Secretary of State of the State of Delaware on May 5, 2014.

In addition, as a result of stockholders’ approval of proposal 5(a) at the Annual Meeting, the Board has amended Section 7.1 of the Company’s Amended and Restated Bylaws (the “Bylaws”) to provide that stockholders can alter, amend or repeal the Bylaws by a majority vote of the outstanding shares. Prior to the amendment, Section 7.1 of the Bylaws provided that stockholders could alter, amend or repeal the Bylaws only if that action was approved by the affirmative vote of at least 80% of the voting power of the Company’s then outstanding voting stock, voting together as a single class.

The foregoing descriptions of the amendments to the Certificate and Bylaws are qualified in their entirety by reference to the Certificate, Bylaws and Certificate of Amendment, which are filed as Exhibit 3.1, Exhibit 3.2 and Exhibit 3.3, respectively, to this Current Report on Form 8-K.

(a) The Annual Meeting was held on May 1, 2014. On March 6, 2014, the record date for the Annual Meeting, 572,757,135 shares of the Company’s common stock were issued and outstanding, of which 496,297,796 were present for purposes of establishing a quorum.

(b) Stockholders voted on the following matters:

(1) Stockholders elected Mr. Richard D. Fairbank, Mr. Patrick W. Gross, Ms. Ann Fritz Hackett, Mr. Lewis Hay, III, Mr. Benjamin P. Jenkins, III, Mr. Pierre E. Leroy, Mr. Peter E. Raskind, Mr. Mayo A. Shattuck III, Mr. Bradford H. Warner and Ms. Catherine G. West to the Board for terms expiring at the 2015 annual meeting of stockholders;

(2) Stockholders ratified the selection of the firm Ernst & Young LLP to serve as the independent auditors of the Company for 2014;

(3) Stockholders approved the Company’s Third Amended and Restated 2004 Stock Incentive Plan;

(4) Stockholders approved, on an advisory basis, the Company’s 2013 named executive officer compensation; and

(5) Stockholders approved amendments to the Certificate to remove supermajority voting standards applicable to the following actions:

(a) Future amendments to the Bylaws and Certificate; and

(b) Removing any director from office;

Stockholders did not approve amendments to the Certificate to remove supermajority voting standards applicable to the following actions:

(c) Certain business combinations.

(6) Stockholders did not approve a stockholder proposal requiring an independent Board chairman.

As described in the proxy statement for the Annual Meeting, each of the proposals to approve amendments to the Certificate required approval of at least 458,205,708 shares, representing 80% of the Company’s common stock outstanding. Proposal 5(c) additionally required, but despite the Company’s solicitation efforts did not obtain, approval by 80% of the Company’s common stock outstanding not owned directly or indirectly by any Interested Stockholder or any Affiliate of any Interested Stockholder (as defined in the Certificate).

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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.

(d) Exhibits

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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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