Welcome to San Mateo County

San Mateo County is a county in the State of California that is located south of San Francisco County and covers most of the San Francisco Peninsula. The San Francisco Airport is actually located in the northeastern area of the county even though the airport itself has a San Francisco postal address. The county has a population of more than 750,000 and Redwood City is the county seat. San Mateo County is the home of Visa Inc, Sony Interactive Entertainment, YouTube, GoPro, Genentech, Facebook among others.