X0306 4 2023-02-28 0 0001501585 HUNTINGTON INGALLS INDUSTRIES, INC. HII 0001852543 Wilkinson Kara R. C/O HUNTINGTON INGALLS INDUSTRIES 4101 WASHINGTON AVE NEWPORT NEWS VA 23607 0 1 0 0 Ex. VP and President, Ingalls Common Stock 2023-02-28 4 A 0 1199 215.20 A 3916.588 D Common Stock 2023-02-28 4 F 0 570 215.20 D 3346.588 D The Huntington Ingalls Industries, Inc. Compensation Committee determined that all performance goals had been met for these restricted stock units, and they were issued on February 28, 2023. Shares withheld by the issuer for the payment of withholding taxes on restricted stock that vested on February 28, 2023. /s/ Kathy S. Owen, Attonrey-in-Fact for Kara R. Wilkinson 2023-03-02