Los Altos is a city in Santa Clara County, California, in the San Francisco Bay Area. The population was 31,625 according to the 2020 census. Most of the city's growth occurred between 1950 and 1980. Originally an agricultural town with many summer cottages and apricot orchards, Los Altos is a bedroom community on the western edge of Silicon Valley, serving as a major source of commuters to other parts of Silicon Valley.