Costco ecommerce sales in its fiscal Q3 2026 grew by at least 20% for the third consecutive quarter and 10% for the 10th straight quarter.
Costco net sales in Q3 increased 11.6%, to $69.15 billion in 2026 from $61.97 billion last year. Through the first three quarters of its fiscal 2026, Costco net sales increased 9.6% year over year, to $203.37 billion from $185.48 billion. Net income for Costco’s Q3 was $2.19 billion, up from $1.90 billion a year ago.
Meanwhile, Costco comparable sales in the U.S. grew 9.4% year over year in Q3. In Canada, Costco comparable sales increased 10.7%, with 11.2% growth through the rest of its international business.
Total Costco comparable sales increased 9.8% year over year in its Q3. Comparable sales account for those from stores Costco operated in both periods, as well as those through ecommerce channels.
The retailer noted that its comparable sales figures exclude the impacts from changes in gasoline prices and foreign exchange. CEO Ron Vachris and chief financial officer Gary Millerchip also addressed the impacts of gas prices and tariff refunds on Costco’s business.
“We have relatively low inventory exposure to shipping issues stemming from the situation in the Middle East, but we continue to monitor the situation closely,” Millerchip told analysts on Costco’s Q3 earnings call.
Costco is No. 7 in the Top 2000 Database. The database is Digital Commerce 360’s ranking of the largest online retailers in North America by their annual ecommerce sales. It’s also the fourth-largest Mass Merchant in the database.
Costco ecommerce sales in fiscal Q3 2026
In its fiscal Q3 2026, Costco ecommerce sales increased 21.5% year over year. That’s similar to the growth rate through the first three quarters, which was 21.6%.
Total Costco revenue in Q3 reached about $70.53 billion. That was about 11.6% year-over-year growth.
“In digital, we’re making meaningful strides to deliver a more seamless and convenient experience for our members across the warehouse and online,” Vachris said.
Among those, he said, are improvements to the mobile wallet, introduction of digital membership card quick access on the Costco app, and the rollout of its shopping cart pre-scan tool internationally.
Traffic to the Costco ecommerce website and mobile app increased 37% year over year in Q3, Millerchip said. Pharmacy, gold and jewelry, home furnishings, tires, special events, housewares and majors all grew double digits year over year, he added.
Millerchip said Costco’s personalized product recommendation carousels delivered conversion rates three times better than its typical conversion rates. Those personalized recommendation carousels contributed “just under” half a billion in Costco ecommerce sales during Q3, Millerchip stated.
Costco’s average same-day delivery time in the U.S. is now less than 45 minutes, Vachris said.
“This part of our business is growing at an even faster rate than our digital business overall and is a strong driver of loyalty as it is often our highest spending members who are using this service,” Vachris said.
Millerchip also noted that Costco is broadening its retail media reach. He said Q3 marked the launch of a new collaboration with Google Commerce Media and YouTube. That partnership will make it easier for brands and agencies to collaborate with Costco’s retail media network, according to Millerchip. He called it a “significant milestone” in Costco increasing its share of retail media revenue.
How AI is helping grow Costco’s digital sales in Q3
Vachris added that as Costco learns more about how consumers are using AI to shop, it’s working with AI companies to improve its visibility to current and potential future Costco members.
“We believe AI is changing how consumers research products and has the potential to be a significant opportunity for Costco given our pricing authority and our focus on quality,” Vachris said.
Millerchip added to that.
“We’re now leveraging AI to enhance our product pages online, which, in turn, is increasing our relevance with the large language models,” Millerchip said. “While the volume of traffic generated from AI search is still low, we saw triple-digit growth in Q3, and this activity has the highest conversion rate of all traffic coming to our site.”
How many members did Costco have in Q3?
Costco ended its Q2 with 82.9 million paid household members. That’s 4.1% year over year. It’s also an increase from 82.1 million in Q2.
Of those, 41.2 million had paid executive memberships — 9.6% more than the prior-year period.
Costco also ended Q1 with 148.5 million cardholders, a 4% year-over-year increase. That’s also up from 147.2 million cardholders in Q2.
In Q3, Costco generated about $1.37 billion in membership fee income. That’s 10.7% year-over-year growth, or $133 million more than last year. At the end of Q3, Costco’s U.S. and Canada membership renewal rate was 92.2%. Worldwide, it was 89.7%, unchanged from Q2.
How many countries have a Costco?
As of the end of its fiscal Q3 2026, Costco operates 931 warehouses. Of those, 639 are in the United States and Puerto Rico. Listed by amount, the rest are in:
- Canada (115)
- Mexico (43)
- Japan (37)
- The United Kingdom (29)
- South Korea (20)
- Australia (15)
- Taiwan (14)
- China (7)
- Spain (5)
- France (3)
- Sweden (2)
- Iceland (1)
- New Zealand (1)
Costco operates ecommerce sites in:
- Australia
- Canada
- China
- Japan
- Mexico
- South Korea
- Taiwan
- The United States
- The United Kingdom
Percentage changes may not align exactly with dollar figures due to rounding. Check back for more earnings reports. Here’s last quarter’s update on Costco ecommerce sales.
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