The rapid growth of Buy Now, Pay Later (BNPL) services in Indonesia, especially Shopee PayLater, has created new patterns in consumer behavior and technology adoption in digital finance. While these services offer practical benefits and financial flexibility, they also raise concerns related to data privacy, potential misuse of personal information, and system security. This study investigates the factors influencing users’ behavioral intention to use Shopee PayLater by extending the Technology Acceptance Model (TAM). The proposed model includes six key variables: Perceived Ease of Use, Perceived Usefulness, Perceived Risk, Perceived Security, User Trust, and Intention to Use. A quantitative method was applied by distributing a structured online questionnaire to Shopee users in Indonesia. The data were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results show that Perceived Ease of Use positively influences both User Trust and Intention to Use, although its effect on intention is not statistically significant. Perceived Risk negatively affects both Trust and Intention, with a significant impact on Trust. Perceived Security unexpectedly has a negative but marginally significant effect on Intention to Use. User Trust is found to be a strong and significant predictor of Intention to Use, indicating its central role in mediating other variables in the model. These findings suggest that, beyond ease and usefulness, users’ trust and risk perceptions significantly affect adoption. Strengthening security assurance and reducing perceived risk are essential strategies to improve trust and drive continued use of BNPL services such as Shopee PayLater in the Indonesian digital finance environment.