Patience and risk-taking – two preference components that steer intertemporal decision-making – are fundamental to human capital investment decisions. To understand how they contribute to international skill differences, we combine PISA tests with the Global Preference Survey. We find that opposing effects of patience (positive) and risk-taking (negative) together account for two-thirds of the cross-country variation in student skills. In an identification strategy addressing unobserved residence-country features, we find similar results when assigning migrant students their country-of-origin preferences in models with residence-country fixed effects. Associations of national preferences with family and school inputs suggest that both may act as channels.