Empirical studies analyzing the push factors of expat jihadism are scarce and typically give contradictory results. We hypothesize that youth unemployment, as opposed to overall unemployment, is a significant determinant of foreign fighters flow to join the Islamic State. Moreover, we also consider the interaction between youth unemployment and the Muslim population share as another meaningful variables affecting expat jihadism. Controlling for several variables including gross domestic product per capita; Gini; geographical proximity; the share of manufactures and services as a percentage of Gross Domestic Product; Polity score; and fractionalization, we provide strong evidence for the hypothesis that Muslim youth unemployment is a driver of expat jihadism not only for Muslim-majority countries, but globally.