The rapid evolution of digital technology has significantly transformed many sectors, especially financial services, with the rise of fintech innovations such as Flip. Flip offers interbank transfer services free of administrative fees, simplifying transactions like e-wallet top-ups, bill payments, and international money transfers, attracting a substantial user base. However, despite its popularity, users have raised concerns about transaction delays, slow customer service responses, and design issues, highlighting a gap between user expectations and actual service delivery. This study aims to evaluate user satisfaction with the Flip application using the End User Computing Satisfaction (EUCS) model, which assesses satisfaction across five key dimensions: Content, Accuracy, Format, Ease of Use, and Timeliness. Data from 415 respondents were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) to investigate the factors influencing satisfaction. The findings reveal that user satisfaction with Flip is generally positive, with significant impacts from Content, Format, Ease of Use, and Timeliness. However, Accuracy, while positively related, had no statistically significant effect. These results emphasize the need for improving transaction timeliness and refining content and interface formats to enhance the user experience. The study provides essential insights for Flip developers to enhance service quality and offers a data-driven foundation for future research on fintech applications.