Costco is headquartered in Issaquah, Washington, United States[7] and was founded in 1976 in San Diego, CA[8] with its first warehouse in Seattle.[9] Today, Costco has a total of 657 locations, with retail outlets in the United Kingdom (25), Australia (6), Canada (87), Mexico (33), Taiwan (9), South Korea (11), Japan (15), Spain (1)[10] and the United States (451).[1]