Explore San Anselmo local geography, civic resources and voter guides, with dated official population and registration facts for Marin County.
At a glance: San Anselmo is an incorporated city in Marin County. Population: 12,474 (California Department of Finance estimate as of January 1, 2026). Registered voters: 9,623 (California Secretary of State, as of September 4, 2026).
San Anselmo sits where central Marin's valley routes converge around San Anselmo Creek. Its downtown follows the creek corridor, with residential streets climbing into surrounding wooded hills. Memorial Park provides substantial neighborhood recreation space, while San Anselmo Public Library anchors civic learning near Town Hall. Downtown public spaces bring these resources close to the town's local shopping streets. San Anselmo incorporated on April 9, 1907. It is a general-law town with a council-manager government, administering local matters separately from Ross, Fairfax, and unincorporated valley communities.
Yes. San Anselmo Public Library is a town resource near its civic center.
Memorial Park is a principal town park; consult the town for current field, playground, and reservation information.
Postal and municipal boundaries can differ. Confirm your jurisdiction through Marin County before seeking permits or identifying municipal ballot contests.
9,623 (California Secretary of State, as of September 4, 2026).
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