The database compiles information to analyze the relationship between economic complexity and informality in Brazil between 2003 and 2019. Available variables include the informality rate (tx_infor), the Economic Complexity Index (ice), average years of schooling (esc), average income in the private sector (ren_priv), the total population of the state (pop_tot), and the state's Gross Domestic Product (pib_est). With this dataset, it is possible to apply econometric and statistical methods to investigate how economic complexity relates to levels of informality over time and across different Brazilian states and regions.