California's 15th senatorial district is one of 40 California State Senate districts. It is currently represented by Democrat Dave Cortese of San Jose.
The district encompasses central and eastern Santa Clara County. Most of the district's population lives in San Jose, but it also includes some outlying areas like Mount Hamilton, Coyote, Sveadal, Morgan Hill, and Gilroy.
Due to redistricting, the 15th district has been moved around different parts of the state. The current iteration resulted from the 2021 redistricting by the California Citizens Redistricting Commission.