San José de Mayo is a city located in the San José Department in southern Uruguay. Situated on the banks of the San José River, the city lies approximately 90 km (56 mi) northwest of the capital, Montevideo.
Founded in 1783 by Spanish colonialists, the city developed into an important administrative and agricultural center for the region. As of 2023, San José de Mayo had a population of 38,553 inhabitants and covers a total area of 16.95 km² (6.54 sq mi).