As of 2021, 16 US states and the District of Columbia have implemented laws allowing undocumented migrants to acquire driver’s licenses. In this paper, I hypothesize that lower barriers to work due to the ability to obtain driver’s licenses can affect undocumented migrants’ fertility decisions. Using a difference-in-differences strategy, I find that these laws were associated with a decline in childbirth among likely undocumented married women. Further analysis suggests that the negative effect of the laws on likely undocumented women’s fertility comes from the rise in the opportunity costs of childbearing, which, in turn (1) increases the usual hours worked among employed undocumented married women and (2) affects the selection into marriage.