The decline in inequality observed in most Latin American countries after 2002 was surprisingly good news, particularly given that most developed countries were experiencing a rise in inequality at that time. Various arguments have been put forward to explain this decline, but there is still no consensus on the most plausible explanation. This article contributes to the ongoing discussion by performing inequality decompositions by factor components. We estimate the importance of each source of income in explaining the observed decline in income inequality between 2002 and 2011 in five Latin American countries. Specifically, we explore the role of the process of formalization that has taken place in regional labor markets, separating formal and informal wages and considering self-employment incomes. In the five countries studied here informal wages and self-employment income contributed to decreasing inequality. Formal sector wages, on the other hand, fostered inequality in all countries except Bolivia.