The study explores the relationship between customer satisfaction and the financial performance of banks, focusing on mediating factors. This study aims to investigate in detail the impact of responsibility, tangibility, and reliability on banks’ financial performance, with a particular emphasis on the mediating function of customer satisfaction. The primary objectives are to analyze how these service quality dimensions influence customer satisfaction and, subsequently, financial outcomes. The research is grounded in the theory that higher levels of customer satisfaction lead to improved financial performance through increased loyalty. Using Employing Partial Least Squares Structural Equation Modelling (PLS-SEM), the study analyzes data collected from commercial bank clients in Kazakhstan over a four-month period, from November 2023 to February 2024. The dataset includes responses from approximately 200 participants, ensuring demographic representation through a stratified random sampling method. Hypotheses regarding customer satisfaction, reliability, responsibility, and tangibility were tested. Findings reveal a significant positive relationship between customer satisfaction and financial performance, indicating that higher satisfaction levels contribute to improved financial outcomes for banks. These findings highlight the multidimensional nature of customer satisfaction and underscore the importance of addressing various factors to enhance financial performance in the banking sector. This study contributes theoretical insights and practical implications for banks aiming to optimize their financial performance through customer-centric strategies.