As of May 13, 2018, Costco operated 749 warehouses including 519 in 44 states, Washington D.C. and Puerto Rico, 98 in Canada, 38 in Mexico, 28 in the UK, 26 in Japan, 14 in South Korea, 13 in Taiwan, 9 in Australia, 2 in Spain, and 1 each in France and Ireland.

In fiscal 2017, the company opened 28 new warehouses and closed 2 existing warehouses. The company opened 10 new warehouses including 2 relocations in the first nine months of fiscal 2018 and plan to open 15 new warehouses, including 2 relocations, for the remainder of fiscal 2018.

At year-end, Costco owned the land and/or the building at 587 store locations, owned the building on leased land at 102 locations and leased 52 store locations. Overall, warehouse clubs averaged 145,000 square feet, with stores in the US averaging 147,000 square feet, stores in Canada averaging 139,000 square feet and other international locations averaging 142,000 square feet.

Store growth2.7%3.6%4.2%3.5%4.6%4.3%
Total gross square feet (M)108,572107,300103,20098,70095,30090,805
Total gross square feet growth3.0%4.0%4.6%3.6%5.0%4.4%
Avg store gross sq ft145,000144,800144,300143,900143,700143,200
Avg store gross sq ft growth0.3%0.3%0.3%0.1%0.4%0.2%