Do institutions or culture determine levels of social trust in society? If quality of institutions determines levels of social trust, migrants from countries with lower-quality institutions should enhance their level of social trust in countries with higher-quality institutions. If, on the other hand, the migrants' level of social trust is determined by their culture, it should not be affected by a different institutional setting. Furthermore, culturally diverse immigrant groups should have different levels of social trust in the same host country. Analysing migration from several non-western countries to Denmark, this paper demonstrates that institutions rather than culture matter for social trust.