This paper uses Colombian micro-data to analyze the role of education and informality in regional wage differentials. The hypothesis is that apart from differences in the endowment of human capital, regional heterogeneity in the incidence of informality is another important source of regional wage inequality in emerging countries. This is confirmed by the evidence from Colombia, which also reveals remarkable spatial heterogeneity in the wage return to individuals' characteristics. Regional heterogeneity in returns to education is especially intense in the upper part of the wage distribution. In turn, heterogeneity in the informal pay penalty is more relevant at the bottom.