This study analyses the effects of the expansion of the highly skilled labour force (higher education) on the per capita income increase in Brazilian municipalities. The results show that a larger highly educated labour force translates into stronger growth in the most developed municipalities with fewer opportunity costs, measured by wage differences. The reduction of regional inequalities fostered by the expansion of higher education over the past 15 years will become sustainable if the increase in the skill supply is accompanied by a rise in demand, so the opportunity costs between factors are reduced and the skill premium grows.