There is no audience in all of retail quite like a Costco member. Not Amazon Prime subscribers. Not Walmart+ members. Not loyalty program cardholders at any grocery chain in the country. The Costco member is a fundamentally different kind of shopper — more committed, more engaged, more purchase-ready, and more valuable to the brands that earn their attention than any other consumer segment in retail today. And in 2026, Costco member loyalty  is not just holding strong — it is