["International Economic Review, EarlyView. ", "\nABSTRACTLarger firms feature (i) longer hours worked, (ii) higher wages, and (iii) smaller (larger) wage penalties for working long (short) hours. We reconcile these patterns in a general equilibrium model, which features the endogenous interaction of hours, wages, and firm size. In the model, workers willing to work longer hours sort into larger firms that offer a wage premium. Complementarities in hours generate wage penalties that increase with the distance from the usual hours. We use the model to argue that variation in average hours across firms contributes significantly to wage inequality."]