In recent years, the financial sustainability of local authorities has been recognised as a concept of crucial importance in ensuring that public services may continue to be delivered to future generations. Although many European countries have implemented programmes to enhance their financial sustainability, local authorities are characterised by differing administrative traditions and achieve diverse outcomes in response to the reforms made. Taking a comparative approach, the present study identifies institutional, macroeconomic and microeconomic factors that might influence local authorities’ financial sustainability in England and Spain in order to determine and explain similarities and differences in the drivers and risk factors for financial sustainability in local authorities’ provision of public services.