Costco (COST) reported net sales of $93.9 billion for its 16-week fiscal fourth quarter ended August 30, 2026, up 11.2% from a year earlier, and earnings of $6.75 a share, up from $5.87 [1]. Comparable sales rose 9.4%, or 6.7% excluding gasoline prices and currency moves, and membership fee income rose 7.3% to $1.85 billion [1][2]. Earnings included a one-time benefit of 15 cents a share from tariff refunds [1]. In September, comparable sales rose 11.4%, the company reported on October 7 [3].
What did Costco report for fiscal Q4 2026?
| Measure | Q4 fiscal 2026 (16 weeks) | Q4 fiscal 2025 | Change |
|---|---|---|---|
| Net sales | $93.87 billion | $84.43 billion | +11.2% |
| Membership fees | $1.85 billion | $1.72 billion | +7.3% |
| Total revenue | $95.72 billion | $86.16 billion | +11.1% |
| Net income | $3.00 billion | $2.61 billion | +14.9% |
| Diluted EPS | $6.75 | $5.87 | +15.0% |
| Comparable sales | +9.4% | n/a | n/a |
| Comparable sales excluding gas and currency | +6.7% | n/a | n/a |
| Gross margin (percent of net sales) | 11.02% | n/a | -0.11 points |
Source: Costco fourth-quarter results and highlights presentation filed with the SEC [1][2].
For fiscal 2026, net sales rose 10.1% to $297.2 billion and net income to $9.23 billion, or $20.76 a share, from $8.10 billion, or $18.21 [1]. Costco ended the year with 939 warehouses, including 647 in the United States and Puerto Rico, and $20.2 billion of cash and equivalents [1][2].
How much did gasoline and tariffs affect the results?
Gasoline
Costco sells gasoline at most of its warehouses, so fuel prices move its sales. US retail gasoline averaged $4.36 a gallon in September 2026, the highest September in the EIA's records, and was $1.23 higher than a year earlier in early October, DataPorium data show [5]. That is why Costco's reported comparable sales growth of 9.4% was well above the 6.7% excluding gasoline and currency [2]. In the United States alone, comparable sales rose 10.7% reported and 7.2% excluding those effects [2]. Gas sales carry thin margins, so they lift revenue more than profit: Costco's reported gross margin fell 0.11 points, but rose 0.20 points excluding the effect of gas [2].
Tariff refunds
Costco said fourth-quarter earnings were "positively impacted by a non-recurring benefit of $0.15 per diluted share from IEEPA tariff refunds received in the quarter, less partial reinvestment of those refunds in increased member values" [1]. The refunds follow the Supreme Court's ruling against tariffs imposed under the International Emergency Economic Powers Act; about $100 billion had been refunded or certified for payment by the end of July, CNBC reported [6]. Without that benefit, EPS would have been about $6.60, still up about 12% from a year earlier [1].
How did Costco's costs and margins change?
Costco runs on thin margins by design. In the fourth quarter, merchandise costs were $83.53 billion against net sales of $93.87 billion, and selling, general and administrative expenses were $8.39 billion [1]. SG&A was 8.94% of net sales, up 0.27 points from a year earlier on a reported basis but up only 0.02 points excluding the effect of gasoline, because higher gas prices inflate sales without adding much to costs [2]. Income before taxes rose 14.2% to $4.01 billion [1].
Costco also said it reinvested part of its tariff refunds in lower prices. Its presentation listed price cuts on Kirkland Signature products, such as walnuts reduced from $13.79 to $9.99 and Colombian whole-bean coffee from $21.99 to $19.99 [2]. Lower prices for members are a long-standing part of Costco's strategy to keep renewal rates high.
Are more people shopping at Costco?
Yes. Comparable traffic, the number of shopping visits, rose 3.3% worldwide in the fourth quarter, and the average ticket rose 5.9% reported or 3.3% excluding gas and currency [2]. In the US, traffic rose 3.2% [2].
Membership, the core of Costco's profit, kept growing. Paid memberships rose 3.8% to 84.1 million, total cardholders rose 3.6% to 150.4 million, and executive memberships reached 42.3 million [2]. The renewal rate was 92.3% in the US and Canada and 89.8% worldwide, and executive members accounted for 75.6% of sales [2].
Digital sales grew faster than stores. Digitally enabled comparable sales rose 19.5%, and traffic to Costco's website and app rose 30%, with pharmacy and home furnishings among the fastest-growing categories [2].
What did Costco report for September 2026?
| Five weeks ended October 4, 2026 | Comparable sales | Excluding gas and currency |
|---|---|---|
| United States | +12.5% | +8.0% |
| Canada | +6.3% | +4.9% |
| Other international | +10.8% | +7.7% |
| Total company | +11.4% | +7.6% |
Source: Costco September sales release, October 7, 2026 [3].
Net sales for the retail month of September were $30.02 billion, up 13.0% from $26.58 billion a year earlier, and digitally enabled sales rose 19.0% [3]. Costco noted that Labor Day fell a week later than in 2025 in the United States and Canada, which added a little more than half a percentage point to September's sales growth [3]. The 7.6% growth excluding gas and currency was a step up from the fourth quarter's 6.7% [2][3].
How has Costco stock performed?
DataPorium data show Costco shares rose 2.9% the day after the report, from $896.48 on September 24 to $922.77 on September 25 [4]. The stock ended September at $910.34, down 2.7% for the quarter but up 5.6% for 2026, and closed at $946.92 on October 9 [4]. Costco opened 11 warehouses in the fourth quarter, including new locations in Mansfield, Texas, and Stone Mountain, Georgia, and plans to reach an estimated 967 warehouses by the end of fiscal 2027 [2].
Costco's fiscal Q4 2026 net sales rose 11.2% to $93.9 billion, with comparable sales up 6.7% excluding gasoline and currency, and its worldwide renewal rate held at 89.8%.
Frequently asked questions
How much did Costco earn in fiscal Q4 2026?
Costco earned $3.00 billion, or $6.75 per diluted share, in the 16-week quarter ended August 30, 2026, including a 15-cent benefit from tariff refunds [1].
What is Costco's membership renewal rate?
The renewal rate was 92.3% in the US and Canada and 89.8% worldwide at the end of fiscal 2026 [2].
How fast are Costco's comparable sales growing?
Comparable sales rose 9.4% in fiscal Q4 2026 and 11.4% in September 2026; excluding gasoline and currency, they rose 6.7% and 7.6% [2][3].
How many Costco warehouses are there?
Costco operated 939 warehouses at the end of fiscal 2026, including 647 in the United States and Puerto Rico, and expects about 967 by the end of fiscal 2027 [1][2].
Sources & References
- [1] Costco, Costco Wholesale Corporation Reports Fourth Quarter and Fiscal Year 2026 Operating Results (Form 8-K exhibit 99.1, September 24, 2026)
- [2] Costco, Q4 fiscal 2026 highlights presentation (Form 8-K exhibit 99.2, September 24, 2026)
- [3] Costco, Costco Wholesale Corporation Reports September Sales Results (October 7, 2026)
- [4] DataPorium Costco (COST) stock page (prices)
- [5] DataPorium Energy (weekly US retail gasoline prices)
- [6] CNBC, Trump admin refunds $100 billion in liberation day tariffs (August 5, 2026)
