Costco reports 9.8% same-store sales growth in Q3 2026, reinforcing the appeal of its membership-led model

Costco Wholesale reported that comparable, or same-store, sales rose 9.8% in its fiscal third quarter, a result the company’s most recent earnings materials framed as broad-based strength across regions. The figure, which excludes the effect of expanding into new locations by focusing on warehouses operating for more than a year, has become one of the clearest benchmarks for how well Costco is converting member traffic into store sales.

For the 12 weeks ended May 10, 2026, net sales increased 11.6% year over year to $69.15 billion, up from $61.96 billion a year earlier. Net income was $2.19 billion, with diluted earnings per share of $4.93. Membership fees, a recurring revenue stream tied to the renewal and growth of Costco’s membership base, rose to $1.373 billion for the quarter from $1.240 billion in the prior year period.

Costco’s comparable sales gains were also visible beyond the headline number. The company reported total-company adjusted comparable sales of 6.6% for the quarter, excluding impacts from changes in gasoline prices and foreign exchange. Adjusted results were 6.8% in the U.S. (9.4% unadjusted), 6.2% in Canada (10.7% unadjusted), and 5.9% in other international markets (11.2% unadjusted).

Digital commerce continued to accelerate alongside in-warehouse performance. Costco reported digitally enabled comparable sales of 21.5% for the quarter, and 20.8% on an adjusted basis. The company defines this category as transactions influenced by digital ordering behavior, and for investors it is often treated as an indicator that Costco can grow sales without relying solely on new store openings.

In its discussion of the quarter, The Motley Fool highlighted what it said were the drivers behind Costco’s 9.8% same-store result, including strong gas sales, higher ticket sizes, and higher traffic. The article also pointed to the stock’s long-run performance, noting a 634% trailing 10-year total return figure as of June 2, and argued that valuation has reflected investor preference for Costco’s perceived stability.

Industry context matters because club retail operates differently than traditional department-store or supermarket models. Costco’s scale and buyer power typically allow it to emphasize price discipline, while the annual membership model can cushion earnings when merchandise demand softens, since membership fees tend to be more recurring than one-time purchases. In this quarter, that structure showed up in the company’s income statement through continued growth in membership fees alongside higher overall sales.

Costco did not provide category-level detail in the earnings release about how much of the comparable sales growth came from specific merchandise lines such as grocery, apparel, or electronics, nor did it offer a granular breakdown of margin drivers. The company also did not publish forward guidance in the release text itself, so it is still unclear whether management expects comparable sales to remain at these levels in the next quarter, especially after adjusting for gas prices and foreign exchange.

Going forward, investors are likely to focus on whether digitally enabled comparable sales can sustain double-digit growth and whether adjusted same-store sales remain resilient as pricing conditions and currency effects fluctuate. Costco’s next quarterly update, including any commentary during its scheduled earnings discussion, should clarify how much momentum is attributable to customer demand versus temporary factors.