
San Anselmo
- County:
- Marin County
- County Seat:
- No
- Area (mi²):
- 2.675
- State:
- California
San Anselmo is a town located in Marin County, California. San Anselmo has a 2025 population of 12,291. San Anselmo is currently declining at a rate of -0.83% annually and its population has decreased by -4.04% since the most recent census, which recorded a population of 12,808 in 2020.
The average household income in San Anselmo is $240,739 with a poverty rate of 5.32%. The median age in San Anselmo is 45.7 years: 44.7 years for males, and 46.2 years for females.