$COST · Costco Wholesale Corporation

Costco Wholesale Corporation filed a Form 4 reporting transactions by John Christopher Sullivan, an Executive Vice President, on October 22, 2026. The filing shows he acquired 4,552 shares of common stock through the vesting of restricted stock units. These units were part of a performance-based grant originally made on October 22, 2025, for which the Compensation Committee determined the fiscal 2026 performance conditions had been satisfied. The earned award vests in annual installments over a five-year period.

On the same date, Sullivan disposed of a total of 3,763.249 shares to cover tax withholding obligations related to the vesting of previously granted restricted stock units. Each of these withholding transactions was executed at a price of $1,018.21 per share, representing the closing market price of Costco common stock on Nasdaq on October 22, 2026. After these transactions, he directly owned 48,459.895 shares of Costco common stock.