Hillsborough is an affluent incorporated town in San Mateo County, California, located on the San Francisco Peninsula. It is situated approximately 17 miles (27 km) south of San Francisco and 7 miles (11 km) north of San Mateo. The town covers an area of approximately 6.2 square miles (16 km²) and has a population of around 11,000 people as of the 2020 United States Census.