The goal of this research was to facilitate the conceptualization the idea of employee wellness consisting of social well-being and work ergonomics in the workplace, aiming to boost employee performance results by considering the workers’ mental health as a mediating variable. The proposal was to fully grasp the effect of these two factors on mental well-being. In order to conduct the study, the sample collected was 496 employees in various banks across West Bengal. Structural equation modelling SPSS AMOS 22 was used to assess the hypothesis and the relationship. The research outcome highlighted the partial mediating role of mental health in the correlation between social well-being and workplace ergonomics. It was worth noting that changes in these two factors significantly impacted employee performance, especially when considering mental health as a mediating factor. Research had shown that changes in work setup and health help employee mental health, leading to a better work environment. The lack of awareness or avoidance of mental health in banking industry issues had led to higher employee ill-health. Mental health emerges as a reliable predictor of better employee performance. It was also a reliable sign of better well-being in many places, as seen in this study, which significantly affects worker work.