Costco Wholesale (COST) Monthly Sales Update September 2026 summary

September sales

• Five-week retail month ran Aug. 31–Oct. 4, 2026, versus Sept. 1–Oct. 5, 2025.

• Net sales were $30.02 billion, up 13.0% from $26.58 billion YoY.

• Reported comparable sales rose 11.4% overall: U.S. 12.5%, Canada 6.3%, Other International 10.8%.

Comparable sales and traffic

• Comparable sales excluding gasoline price and FX impacts: 7.6% overall; U.S. 8.0%, Canada 4.9%, Other International 7.7%.

• Comparable traffic was up 4.7% worldwide and 4.3% in the U.S.

• Labor Day fell one week later in the U.S. and Canada, lifting September total and comparable sales by a little more than 50 bps.

• Gas price inflation added ~3.8% to reported total comparable sales; worldwide average selling price per gallon rose 32.8% YoY.

• Digitally enabled sales increased 19.0% reported and 19.1% excluding FX.

Transactions and regional trends

• Average transaction rose 6.4% worldwide including gas inflation and FX, and 2.8% excluding both.

• FX impact on sales: Canada ~-1%, Other International ~+1.2%, and total company approximately flat.

• Strongest U.S. comparable sales were in the Midwest, Southeast, and San Diego; Spain, Taiwan, and China led Other International in local currencies.

• Cannibalization had an approximately 60 bps negative impact.