Notice of 2022 Annual Meeting of Stockholders The 2022 Annual Meeting of Stockholders of Huntington Ingalls Industries, Inc. will be held on Tuesday, May 3, 2022 at 11:00 A.M. EDT, virtually via the internet at https://meetnow.global/MW6JXNH. To participate in the virtual meeting, you must have the information that is printed in the shaded bar located on the reverse side of this form. Proposals to be voted on at the meeting are listed below. The Board of Directors recommends a vote FOR the 13 director nominees, FOR Proposals 2, 3 and 4 and AGAINST Proposal 5. 1. Elect 13 directors: Philip M. Bilden, Augustus L. Collins, Kirkland H. Donald, Victoria D. Harker, Frank R. Jimenez, Christopher D. Kastner, Anastasia D. Kelly, Tracy B. McKibben, Stephanie L. O’Sullivan, C. Michael Petters, Thomas C. Schievelbein, John K. Welch, Stephen R. Wilson 2. Approve executive compensation on an advisory basis 3. Ratify the appointment of Deloitte & Touche LLP as independent auditors for 2022 4. Approve the Huntington Ingalls Industries, Inc. 2022 Long-Term Incentive Stock Plan 5. Stockholder proposal to reduce the threshold at which stockholders can require a special meeting of stockholders PLEASE NOTE – YOU CANNOT VOTE BY RETURNING THIS NOTICE. To vote your shares you must vote online or request a paper copy of the proxy materials to receive a proxy card. Here’s how to order a copy of the proxy materials and select delivery preferences: Current and future delivery requests can be submitted using the options below. If you request an email copy, you will receive an email with a link to the current meeting materials. PLEASE NOTE: You must use the number in the shaded bar on the reverse side when requesting a copy of the proxy materials. — Internet – Go to www.envisionreports.com/HII. Click Cast Your Vote or Request Materials. — Phone – Call us free of charge at 1-866-641-4276. — Email – Send an email to investorvote@computershare.com with “Proxy Materials Huntington Ingalls Industries, Inc.” in the subject line. Include your full name and address, plus the number located in the shaded bar on the reverse side, and state that you want a paper copy of the meeting materials. To facilitate timely delivery, all requests for a paper copy of proxy materials must be received by April 22, 2022.