Costco Wholesale Corporation has joined our growing, open source, international community because we are aligned with its philosophy to keep costs low and pass on the savings to more than 96 million members in 9 countries and Puerto Rico. Costco — which has become one of the world’s largest membership warehouse clubs today, ranked 15th on the 2017 Fortune 500 list and was “One of the Top 5 Best Workplaces” in 2018, among Fortune 500 companies — opened its 1stlocation in 1976 as the Price Club in a converted airplane hangar in San Diego, CA.