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

Date of Report (Date of earliest event reported): May 23, 2013

ENGILITY HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

(703) 708-1400

(Registrant’s telephone number, including area code)

NOT APPLICABLE

(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):

Approval of the Engility Holdings, Inc. Amended and Restated 2012 Cash Incentive Plan

On May 23, 2013, Engility Holdings, Inc. (the “Company”) held its 2013 Annual Meeting of Stockholders (the “Annual Meeting”) at which the Company’s stockholders approved an amendment and restatement of the Engility Holdings, Inc. 2012 Cash Incentive Plan (as amended, the “Amended and Restated Cash Incentive Plan”). A description of the material terms and conditions of the Amended and Restated Cash Incentive Plan is set forth on pages 55-58 of the Company’s definitive proxy statement for the Annual Meeting filed with the Securities and Exchange Commission on April 12, 2013 (the “Proxy Statement”). The description, a copy of which is filed as Exhibit 10.1 hereto, is incorporated herein by reference. The description of the Amended and Restated Cash Incentive Plan incorporated herein by reference does not purport to be complete and is qualified in its entirety by reference to the full text of the Amended and Restated Cash Incentive Plan, which is filed as Exhibit 10.2 hereto and is incorporated herein by reference.

Approval of the Engility Holdings, Inc. Amended and Restated 2012 Long Term Performance Plan

At the Annual Meeting, the Company’s stockholders also approved an amendment and restatement of the Engility Holdings, Inc. 2012 Long Term Performance Plan (as amended, the “Amended and Restated LTPP”). A description of the material terms and conditions of the Amended and Restated LTPP is set forth on pages 59-67 of the Proxy Statement. The description, a copy of which is filed as Exhibit 10.3 hereto, is incorporated herein by reference. The description of the Amended and Restated LTPP incorporated herein by reference does not purport to be complete and is qualified in its entirety by reference to the full text of the Amended and Restated LTPP, which is filed as Exhibit 10.4 hereto and is incorporated herein by reference.

On May 23, 2013, the Company held the Annual Meeting at the Ritz Carlton Hotel in McLean, Virginia. A total of 13,984,106 shares of the Company’s common stock, out of a total of 17,143,823 shares of the Company’s common stock outstanding and entitled to vote, were present in person or represented by proxies. Each of the proposals is described in detail in the Proxy Statement. The final results for the votes regarding each proposal are set forth below.

Proposal 1 – Election of Directors

The following directors were elected to the Company’s Board of Directors to serve as directors until the Company’s 2016 Annual Meeting of Stockholders and until their respective successors are duly elected and qualified:

Proposal 2 – Ratification of Independent Registered Public Accounting Firm

The appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2013 was ratified.

Proposal 3 – Advisory Vote on Executive Compensation

The Company’s stockholders approved, on a non-binding, advisory basis, the compensation of the Company’s named executive officers as described in the Proxy Statement.

Proposal 4 – Advisory Vote on the Frequency of Advisory Votes on Executive Compensation

The Company’s stockholders voted for one year with respect to the frequency with which the Company’s stockholders are provided a non-binding, advisory vote on the compensation paid to the Company’s named executive officers.

The Company will file an amendment to this Current Report on Form 8-K to report the Company’s decision regarding the frequency of future non-binding, advisory votes on the compensation of the Company’s named executive officers.

Proposal 5 – Approval of the Engility Holdings, Inc. Amended and Restated 2012 Cash Incentive Plan

The Amended and Restated Cash Incentive Plan was approved.

Proposal 6 – Approval of the Engility Holdings, Inc. Amended and Restated 2012 Long Term Performance Plan

The Amended and Restated LTPP was approved.

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.

EXHIBIT INDEX