To what extent do national governments protect the human rights of migrants, and what are the political and economic circumstances associated with more robust protection? To address these questions, we leverage a rigorous, novel database of migrant rights derived from international laws and standards. We evaluate the extent to which 64 indicators—divided into 17 different categories of migrant rights—appear in national statute and case law in 45 of the world's principal destination states. We find that 61% of the indicators of migrant rights in the Migrant Rights Database, derived from the international human rights baseline, are reflected in the letter of national law—nearly two out of every three. However, we also find that national authorities implement these de jure protections 71% of the time. Taken together, about 44% of migrant rights are both protected and implemented in the countries examined. In a correlational analysis, we find that governments tend to protect more rights when their countries are more democratic, maintain more independent judiciaries, protect more rights in their constitutions, ratify more human rights treaties, permit stronger civil society, and are characterized by more political stability. There is also a weak trade-off between de jure migrant rights protections and the number of migrants a country admits.