California's 13th senatorial district is one of 40 California State Senate districts. It is currently represented by Democrat Josh Becker of Menlo Park.
The district encompasses the southern Bay Area, taking in most of San Mateo County such as the communities of South San Francisco, Pacifica, San Bruno, Millbrae, Burlingame, San Mateo, Foster City, El Granada, Hallf Moon Bay, San Carlos, Redwood City, Woodside, and Menlo Park; along with the western Santa Clara County communities of Palo Alto, Stanford, Mountain View, Cupertino, Campbell, Saratoga, and Los Gatos.
Due to redistricting, the 13th district has been moved around different parts of the state. The current iteration resulted from the 2021 redistricting by the California Citizens Redistricting Commission.