The consideration set has been widely studied as a consumer tool to simplify purchase decisions. However, important questions remain about how a retailer’s private label strategy may impact consumers’ consideration sets. In the present study, we employ the Associative Network Theory of Memory as a theoretical foundation and examine how private label consideration at the retailer level may affect consumers’ decision-making at the product category level. Results from two empirical studies indicate that a higher number of private labels considered at the retailer level enhances consideration set heterogeneity at the category level. Critically, this stimulated heterogeneity further increases the purchase probability of private labels in consumers’ consideration sets. This chain of effect also adds explanatory power to the impact of private label attitude on private label purchase probability through serial mediation. Consequently, retailers are encouraged to dilute consumers’ consideration sets by constructing and communicating a diverse private label portfolio.