Atherton is an incorporated town in San Mateo County, California, United States. Its population was 6,914 as of 2010.
Atherton is known for its wealth; in 1990 and 2019, Atherton was ranked as having the highest per capita income among U.S. towns with a population between 2,500 and 9,999, and it is regularly ranked as the most expensive ZIP Code in the United States.