This study examines the influence of mental accounting, financial attitudes, financial knowledge, and financial self-efficacy on the financial behavior of diligent students in using fintech. This study differs from previous research because it uses a sample of students who already have a business and often use fintech. Data collection was carried out through the distribution of questionnaires to respondents. This study found that financial attitudes and self-efficacy had a significant effect on financial behavior, while financial knowledge had no significant effect on financial self-efficacy and mental accounting. Mental accounting significantly affects financial attitudes, financial behavior, and financial self-efficacy. These findings prove the importance of mental accounting in increasing the confidence and effectiveness of students who often use fintech and have a business in making financial decisions. This research contributes to developing the theory of planned behavior in the context of financial behavior. It reveals that financial literacy does not necessarily increase financial self-efficacy and mental accounting, especially among students who often use fintech and are just starting a business.

The prolonged duration of the Covid epidemic has contributed to the challenging situation faced by land-based Micro, Small, and Medium Enterprises (MSMEs), leading to difficulties in meeting tax obligations. This study aims to identify the factors causing low tax compliance among micro, small, and medium-sized businesses. Employing quantitative methods, the research relies on primary sources and specifically focuses on small and medium-sized companies in Sidoarjo Regency. Purposive sampling was employed, resulting in the inclusion of 164 micro, small, and medium-sized firms meeting the specified criteria. Data analysis was conducted using Structural Equation Modeling Partial Least Square. The study reveals that supply chain sustainability significantly and positively influences taxpayer compliance. Additionally, supply chain sustainability, quality of staff tax services, financial attitudes, and tax comprehension all demonstrate substantial and positive impacts on taxpayer compliance. Indirectly, Supply Chain Sustainability, Tax Employee Service Quality, Financial Attitude, and Tax Understanding exert a significant influence on Development Sustainability in Sidoarjo Regency, East Java Province, Indonesia, through Taxpayer Compliance as an intervening variable for MSMEs. This research contributes to the existing literature by confirming that taxpayer compliance is influenced by Supply Chain Sustainability, Tax Employee Service Quality, Financial Attitude, and Tax Understanding. Furthermore, the study validates the application of the theory of planned behavior in exploring the moderating effect of tax compliance between Supply Chain Sustainability, Tax Employee Service Quality, Financial Attitude, and Tax Understanding on development sustainability, particularly in the context of developing countries.