X0306 4 2021-04-01 1 0001501585 HUNTINGTON INGALLS INDUSTRIES, INC. HII 0001594313 Cuccias Brian J. 4101 WASHINGTON AVENUE NEWPORT NEWS VA 23607 0 1 0 0 Ex. VP & President, Ingalls Common Stock 2021-04-01 4 A 0 979 204.23 A 61152.513 D SEP Unit Common Stock 78.28 332.809 D Total amount includes 979 restricted stock rights granted under the Huntington Ingalls Industries, Inc. 2012 Long-Term Incentive Stock Plan ("HII LTISP") on 04/01/2021, with 100% vesting on 04/01/2022. The reporting person's interest in the HII Stock Fund of the Huntington Ingalls Industries, Inc. Savings Excess Plan (the "Plan") is held in the form of units of interest. The Plan's administrator calculates the number of shares of issuer common stock represented by units in the HII Stock Fund. /s/ Kathy S. Owen, Attorney-in-Fact for Brian J. Cuccias 2021-04-05