Costco

Costco enjoys multiple overlapping moats. Its membership model (over 100M members, ~92–93% renewal) creates a form of customer lock-in and recurring revenue. Its wholesale format drives unmatched buying power (only Sam’s Club is comparable) and low per-unit operating costs.

Stores are no-frills and minimally advertised, allowing Costco to operate on far lower operating costs (roughly half its peers per dollar sales). This cost advantage enables loss-leader pricing on staples, preserving market share and deterring new entrants.

While Morningstar rates Costco’s moat as “narrow,” we view the combination of cost leadership, scale (thousands of stores globally), a strong private-label brand, and high member loyalty as a durable multi-faceted moat likely to persist for years.