Pleasanton is a city in Alameda County, California, United States. Located in the Amador Valley, it is a suburb in the East Bay region of the San Francisco Bay Area. The population was 79,871 at the 2020 census. In 2005 and 2007, Pleasanton was ranked the wealthiest middle-sized city in the United States by the Census Bureau. Pleasanton is home to the headquarters of Safeway, Workday, Ellie Mae, Roche Molecular Diagnostics, Blackhawk Network Holdings, and Veeva Systems.