This study aims to investigate the role of ESG (Environmental, Social, and Governance) practices in fostering employee inclusivity, examining specifically the mediating effects of employee well-being dimensions: happiness, relationships, and health. Based on the literature review, the research formulated a conceptual model depicting the relationships between ESG initiatives, dimensions of employee well-being, and employee inclusivity. A confirmatory factor analysis using structural equation modeling (SEM CFA) was employed to test the model empirically. Data were collected in 2024 through a computer-assisted web interviewing (CAWI) method from a representative sample of 1070 economically active Polish employees. Results confirmed a significant positive relationship between ESG practices and employee inclusivity, predominantly mediated by three dimensions of well-being: happiness, relationships, and health. While the direct ESG-inclusivity link was modest and statistically nonsignificant, the indirect effect through well-being was robust and highly significant, emphasizing that ESG practices primarily enhance inclusivity by positively influencing employee well-being. The study provides empirical validation of a conceptual model linking ESG practices to employee inclusivity via well-being dimensions. It underscores the necessity for organizations to integrate ESG strategies that holistically enhance employee happiness, relationships, and health to foster inclusivity and sustainable organizational effectiveness.