Local government officials are accountable to citizens, who increasingly demand more transparency given the amount of taxes they pay. This paper analyses the relationship between municipal tax revenues and transparency in Spain. Based on a sample of 141 Spanish municipalities with more than 15,000 inhabitants and applying least squares regression and instrumental variable analysis based on two-stage least squares regression, we find that the most transparent municipalities collected more global taxes. Furthermore, more municipal financing through transfers from other levels of government leads to lower taxes on construction and capital gains generated by real estate transfers.