The relationship between immigration and terrorism is an important public policy concern. Using bilateral migration data for 174 countries from 1995 to 2015, we estimate the relationship between levels of immigration and terrorism using an instrumental variables (IV) strategy based on the initial distribution of immigrants in destination countries. We specifically investigate rates of immigration from Muslim Majority Middle Eastern and North African (MENA) countries and countries engaged in conflicts. We find no relationship between stocks of immigrants and terrorism, whether measured by the number of attacks or victims, in destination countries.