Why is there a persistent gender gap in the managerial labor market? Although numerous studies confirm women’s underrepresentation, only a small body of work has examined the reasons behind these gender gaps along the corporate hierarchy. We argue that constraints on female managers’ mobility across firms could be a reason. When these constraints are reduced, female managers are more likely to be promoted than their male counterparts. To empirically test the argument, we use a unique dataset documenting the career histories of over 6,600 female and 60,000 male mid- and top-level managers within about 18,000 U.S. firms from 1993 to 2014. By leveraging exogenous increases in a state-level policy over time, we find that there is a significant average gender gap: female managers are less than half as likely as male managers to be promoted. Furthermore, the reduction in mobility constraints appears to benefit female managers in career advancement along the corporate hierarchy. These findings underscore the importance of accounting for mobility constraints when investigating gender gaps along the corporate hierarchy and when designing policies to reduce such gender gaps in the managerial labor market.