SummaryThe current study utilizes social identity theory to investigate employees' work hours. Specifically, we use meta-analysis to examine the relationships between hours worked and indicators of organizational identity (e.g., organizational support and tenure), occupational identity (e.g., human capital investments and work centrality), and family identity (e.g., family responsibilities and family satisfaction). The meta-analysis also allowed us to explore other important correlates of hours worked (e.g., situational demands, job performance, mental health, and physical health), moderating variables (e.g., age, gender, and job complexity), and curvilinear relationships of work hours to social identity indicators. Overall, we found that occupational factors and situational demands had the strongest relationships with hours worked, hours worked were negatively associated with measures of employee well-being, gender had several significant moderating effects, and there were curvilinear relationships between hours worked and well-being and work-family conflict variables. The article concludes with directions for future theoretical and empirical research.