The growing prominence of private label brands (PLBs) in global retailing has increased consumer engagement, with some studies suggesting that PLBs foster emotional bonds comparable to national brands (NBs). However, other research posits that PLB choices are primarily driven by price considerations or low brand involvement. This study reconciles these perspectives by examining the moderated mediation effect of price and brand sensitivity on the relationship between store trust and PLB loyalty via attitude. Drawing on survey data from 479 French PLB consumers in the fruit juice and cosmetics categories, this study employs Partial Least Squares Structural Equation Modeling (PLS-SEM) to test the conditional effects of price and brand sensitivity, offering a robust alternative to the Hayes Macro process. The results reveal that the full mediation effect of attitude in the store trust–PLB loyalty relationship is amplified among both price-sensitive and brand-sensitive consumers. These findings offer significant theoretical contributions and actionable managerial implications for retailers seeking to optimize PLB positioning and consumer loyalty strategies.