UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (date of earliest event reported): February 25, 2014

ARLINGTON ASSET INVESTMENT CORP.

(Exact name of Registrant as specified in its charter)

1001 Nineteenth Street North

Arlington, VA 22209

(Address of principal executive offices) (Zip code)

(703) 373-0200

(Registrant’s telephone number including area code)

N/A

(Former name or former address, if changed from 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:

As previously disclosed, on May 24, 2013, Arlington Asset Investment Corp. (the “Company”) entered into separate equity distribution agreements (the “Equity Distribution Agreements”) with each of RBC Capital Markets, LLC, JMP Securities LLC, Ladenburg Thalmann & Co. Inc. and MLV & Co. LLC (each, a “Sales Agent” and together, the “Sales Agents”), pursuant to which the Company may offer and sell, from time to time, up to 1,750,000 shares of the Company’s Class A common stock, $0.01 par value per share (the “Shares”).

On January 22, 2014, the Company filed a Registration Statement on Form S-3 (File No. 333-193478) (the “Registration Statement”) with the Securities and Exchange Commission (the “Commission”), which Registration Statement included a base prospectus. The Commission declared the Registration Statement effective on February 5, 2014. On February 25, 2014, the Company filed a prospectus supplement pursuant to Rule 424(b)(5) under the Securities Act of 1933, as amended, to register the Shares under the Registration Statement.

On February 25, 2014, Hunton & Williams LLP issued an opinion with respect to the legality of the issuance and sale by the Company of the Shares to be sold pursuant to the Equity Distribution Agreements, a copy of which is filed as  Exhibit 5.1 to this Form 8-K.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this Report to be signed on its behalf by the undersigned hereunto duly authorized.

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