
Issaquah, Washington-based Costco Wholesale Corporation (COST) operates a chain of membership-only big-box warehouse club retail stores. With a market cap of $421.1 billion, Costco operates through its outlets spread across North America, Asia, and Europe, and an e-commerce website.
Companies worth $200 billion or more are generally described as "mega-cap stocks." Costco fits right into that category, with its market cap exceeding this threshold, reflecting its substantial size, influence, and dominance in the discount retail industry.