Abstract Homogeneous societies usually provide more public goods. Voluntary social distancing in a pandemic is also a public good, but it has private benefits, too. Theoretically, we show that presence of population groups with different rationales for social distancing can lead to stricter observance of social distancing in more diverse societies. Empirically, we find that mobility reduction following the first local COVID-19 case was stronger in Russian cities with higher ethnic fractionalization and xenophobia. For identification, we predict the timing of the first case using historical patterns of internal migration. Using the United States data on mobility produces similar results.