Brand engagement and eWOM intention have been found to be critical factors driving competitive advantage for companies, as the evolution of social networking sites has changed the perspective of how companies engage with customers. Based on social exchange theory, the current research proposes an empirical model that emphasizes (1) the unique role of social commerce characteristics, including personalization, socialization, and information availability, in enhancing consumer-brand engagement, (2) the connection between consumer-brand engagement and eWOM intention, and (3) the moderating influence of trust towards such connection. A survey of 248 Facebook users with online shopping experience was employed. By using PLS-graph 3.0, structural equation modelling, the findings demonstrate that personalization and socialization positively influence brand engagement, which in turn leads to eWOM intention. Furthermore, trust moderates the brand engagement-eWOM intention relationship. Unexpectedly, information availability has shown no significant effect on brand engagement. The study encompasses the knowledge of social exchange theory into the social commerce environment by investigating the linkage between the social commerce environment and brand engagement. It contributes value to marketing theories by describing the moderating role of trust from the viewpoint of Gen Y. In addition, the study’s findings may shed light on how firms in emerging markets can increase competitiveness by stimulating brand engagement and eWOM intention, as well as enhancing consumer trust in the comments regarding the products/services within the social commerce environment.