•We analyse gender gaps in firms’ loan demand and financing constraints.•Differences in credit constraints significantly vary with the definition of gender.•Estimated gaps increase as more precise measures of female participation are used.•We propose a decomposition method to assess the causes of gender differences.•Decomposition results provide support to the hypothesis of gender discrimination. This paper investigates the existence of gender differences in firms’ access to finance. Based on firm-level data for 28 transitional European countries, we show how estimated gender gaps in credit demand and financial constraints significantly depend on the way in which female participation in ownership and management is measured. Furthermore, we find that differences in credit denial probability are not explained by the observed firm characteristics considered, but are due instead to unexplained factors, thus providing support to the hypothesis of gender-based discrimination in access to credit against women-led businesses.