Identifying antecedents of well-being at work is an active field of research, focusing notably on organizational practices that promote employees’ optimal health. To date, whereas studies have demonstrated that some organizational practices, considered in isolation, are positively associated with indicators of well-being, none tested the joint effect of a bundle of practices on these. Moreover, few studies have examined the psychological mechanisms underlying these relationships. The present study aimed to identify the relationships between virtuous organizational practices, a new psychological integrative construct, and three indicators of workers’ hedonic, eudaimonic, and social well-being, namely job satisfaction, thriving at work, and work–life balance, and to test the mediational role of psychological capital in these relationships. The sample comprised 400 French employees working in non-profit, private, and public organizations. Structural equation modeling confirmed the direct effects of virtuous organizational practices on the three indicators of well-being, and a bootstrapping procedure demonstrated that psychological capital partially mediates these relationships. The results of this study have many practical applications because virtuous organizational practices can easily be implemented and optimized in work organizations to develop the individual resources of workers and, in detail, to promote their psychological well-being. Finally, the contributions of this study, avenues for future research, and limitations are discussed.