This research aims to understand the factors explaining household debt for homeownership in Portugal, from 1980 to 2014. For this purpose we used time series with annual data available at Banco de Portugal, Instituto Nacional de Estatística, Direção Geral do Emprego e das Relações do Trabalho and EUROSTAT. The regression model was estimated in first-differences with ordinary least squares (OLS). The results confirm the behavior of nominal interest rates (-) as an explanatory factor of household debt for homeownership. The results also show that the behavior of other variables such as real GDP (+), real GDP per capita (-), the expected inflation rate (+), infant mortality rate (+), gender inequality/equality (-), divorces (+), the total balance of the population (-) and the birth rate (-), also affected significantly household debt for homeownership in Portugal, in the period under analysis.