Abstract Using cognitive theories and behavioral sciences in the field of new businesses, the main purpose of this study is to analyze customer behavior in terms of their satisfaction, perceived usefulness, and confirmed expectations using a combination of financial self-efficacy and technology self-efficacy theories to leverage fintech services. In this research, after establishing the conceptual model, eleven research hypotheses were tested using partial least squares structural equation modeling (PLS-SEM) with a sample size of 205 customers of fintech businesses through an electronic questionnaire. The reliability and validity of the questionnaires were assessed and confirmed using Cronbach's alpha, composite reliability, and average variance extracted (AVE), and expert opinions familiar with the subject matter were consulted for content validity confirmation. This study enhances our understanding of the importance of financial and technological self-efficacies in the field of fintech, and elucidates their distinct impacts on users' intention to use fintech services. Additionally, this study uncovers intriguing findings in fintech user behavior and illustrates that these self-efficacies, by generating perceived usefulness and confirmng user expectations, can lead to satisfaction and, consequently, users' intention to use fintech.