Product market competition and gender discrimination

•We study empirically the link between competition and gender discrimination.•We use a comprehensive business registration reform in Portugal as a quasi-natural experiment.•We use employer-employee data for the universe of private sector firms and workers.•Discriminatory employers grow less over time following the reform and are more likely to exit the market.•The female employment share growth increases following the reform.•The reform reduces the gender pay gap for skilled workers and executives.