Core & Main, Inc.

Director and Officer Trading Arrangements

Item 408(a) of Regulation S-K requires the Company to disclose whether any of its directors or officers have adopted orterminated (i) any trading arrangement that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c); and/or (ii) any written trading arrangement that meets the requirements of a “non-Rule 10b5-1 trading arrangement” as defined in Item 408(c) of Regulation S-K. During the quarter ended August 3, 2025, the following activity occurred requiring disclosure under Item 408(a) of Regulation S-K.

Stephen O. LeClair, Executive Chair and Chair of the Board, adopted a new trading arrangement on July 17, 2025 providing for the sale of up to 300,000 aggregate shares of the Company’s Class A common stock between October 17, 2025 and April 17, 2026.

Mark G. Whittenburg, General Counsel and Secretary, adopted a new trading arrangement on July 15, 2025 providing for the sale of up to 50,000 aggregate shares of the Company’s Class A common stock between October 14, 2025 and April 14, 2026.

Bradford A. Cowles, President, adopted a new trading arrangement on July 11, 2025 providing for the sale of up to 100,000 aggregate shares of the Company’s Class A common stock between October 10, 2025 and April 10, 2026.

The Irrevocable Trust FBO D. G. Gipson, affiliated with Dennis G. Gipson, Director, adopted a new trading arrangement on June 27, 2025, providing for the sale of up to 25,000 aggregate shares of the Company’s Class A common stock between September 26, 2025 and March 26, 2026.

Each of the above trading arrangements is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act and the Company’s Policy on Trading in Securities.