Despite the social importance of universities and their significance as receivers of public funds, hardly any research exists about their disclosure of financial information. The scarce research that has been done has focused on countries such as the United States, New Zealand, Austria, the United Kingdom and Norway. In addition, the Internet is used widely on behalf of public bodies as a way to improve their relations with citizens, through greater disclosure of information and the possibility of doing administrative business and paperwork online. Considering both topics, this work has a twofold objective: (1) to analyse the disclosure of information revealed online by Spanish universities, focusing on several issues, such as financial information, corporate governance, social responsibility and strategy, teaching and research activities, etc.; and (2) to observe the factors that explain the disclosure of financial information through Spanish universities' websites, focusing mainly on size, leverage, university profitability, governance, type of university, research orientation, age of the university and its internationality etc. This study takes into account the whole population of Spanish universities (70 universities: 48 public and 22 private). The findings obtained emphasize that university websites mainly disclose information on teaching and research activities and on governing bodies; to a lesser extent, they reveal information on their social responsibility and strategic aspects; and finally, the volume of financial information disclosed remains quite small, mainly including their budgets. Furthermore, the universities with lower levels of leverage disclose more information online, whereas those with higher volumes of debt are more reluctant to reveal their internal situation on the Internet.