Kirkland Signature private label

Costco's own brand, sold across food, household, apparel and other categories at lower prices than national brands. It is a large part of the warehouse assortment and is central to the margin model, because it lets Costco keep prices low without cutting its merchandise margin.

Why it matters to the stock. Rising Kirkland penetration supports gross margin and loyalty. Traders watch it for signs of share gain from national brands and for tariff pass-through.