Notice of Sale of Securities

On December 19, 2025, Kenneth D. Denman, a director at Costco Wholesale Corp, reported a disposition of 325 shares of Common Stock. The transaction, coded as a gift (G) with a transaction price of $0.00, resulted in a post-transaction ownership of 5663.936 shares. The gift was made to a charitable donor-advised fund, as indicated by footnote F1. The filing, a Form 4, was signed on December 22, 2025, by Alejandro Torres, Attorney-in-Fact.