X0508 4 2023-08-29 0000861884 RELIANCE STEEL & ALUMINUM CO RS 0001447652 HOFFMAN JAMES DONALD C/O RELIANCE STEEL & ALUMINUM CO. 16100 N. 71ST STREET, SUITE 400 SCOTTSDALE AZ 85254 1 0 0 0 1 Common Stock 2023-08-29 4 S 0 10000 285.76 D 114042 I Held by Hoff Holdings Limited Partnership Common Stock 2023-08-30 4 S 0 1100 286.22 D 112942 I Held by Hoff Holdings Limited Partnership Common Stock 2023-08-30 4 S 0 1773 287.37 D 111169 I Held by Hoff Holdings Limited Partnership Common Stock 2023-08-30 4 S 0 5947 288.17 D 105222 I Held by Hoff Holdings Limited Partnership Common Stock 2023-08-30 4 S 0 1180 289.05 D 104042 I Held by Hoff Holdings Limited Partnership Common Stock 19680 D Common Stock 1189 I Held by Trustee of Reliance Steel & Aluminum Co. Employee Stock Ownership Plan Common Stock 3673 I Held by Trustee of Reliance Steel & Aluminum Co. 401(k) Plan The price reported represents the weighted average sale price of the shares disposed of. The actual sale prices ranged from $285.20 to $286.13. The Reporting Person has provided to the Issuer, and hereby undertakes to provide upon request by the U.S. Securities and Exchange Commission staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. Hoff Holdings Limited Partnership ("Hoff Holdings") is a limited partnership of which a revocable trust established by the Reporting Person and his spouse is both the sole member of the sole general partner and also a limited partner, and various trusts for the benefit of the Reporting Person's spouse and his adult children are the other limited partners. The Reporting Person disclaims beneficial ownership over the Issuer's common stock held by Hoff Holdings except to the extent of his pecuniary interest therein. The August 30, 2023 sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 28, 2023. The price reported represents the weighted average sale price of the shares disposed of. The actual sale prices ranged from $285.73 to $286.72. The Reporting Person has provided to the Issuer, and hereby undertakes to provide upon request by the U.S. Securities and Exchange Commission staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. The price reported represents the weighted average sale price of the shares disposed of. The actual sale prices ranged from $286.74 to $287.74. The Reporting Person has provided to the Issuer, and hereby undertakes to provide upon request by the U.S. Securities and Exchange Commission staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. The price reported represents the weighted average sale price of the shares disposed of. The actual sale prices ranged from $287.78 to $288.77. The Reporting Person has provided to the Issuer, and hereby undertakes to provide upon request by the U.S. Securities and Exchange Commission staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. The price reported represents the weighted average sale price of the shares disposed of. The actual sale prices ranged from $288.80 to $289.35. The Reporting Person has provided to the Issuer, and hereby undertakes to provide upon request by the U.S. Securities and Exchange Commission staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price. /s/ James Donald Hoffman by William A. Smith II as his Attorney-in-Fact 2023-08-31