Social commerce (s-commerce) integrates social media with e-commerce, creating new opportunities for consumers and businesses. However, the success of s-commerce depends heavily on perceived risks and trust, which influence consumer decisions. Despite growing research, the interaction between different types of risks: financial, security, and time risks and various trust dimensions, such as merchant competence and merchant integrity, remains underexplored. This study addresses this gap by proposing a predictive model to examine these relationships, focusing on Instagram-based shopping. A quantitative approach was used, with an online survey administered to 267 university students across three UAE universities, analyzed using Structural Equation Modeling (SEM-PLS). The findings show that all three perceived risks significantly impact both merchant competence and merchant integrity, with security risks having the strongest effect on competence. The study underscores the importance of addressing these risks to build trust in s-commerce platforms. However, the sample’s limitation to Generation Z students in the UAE suggests the need for broader research.