Costco Wholesale Corporation (doing business as Costco Wholesale and also known simply as Costco) is an American multinational corporation which operates a chain of membership-only (needing a membership to shop there) big-box retail stores. As of 2020, Costco was the fifth largest retailer in the world, and the worlds largest retailer of choice and prime beef, organic foods, rotisserie chicken, and wine as of 2016.