Kensington is an affluent unincorporated community and census designated place located in the East Bay, part of the San Francisco Bay Area, in Contra Costa County, California, United States. The population was 5,077 at the 2010 census.


The Kensington Branch Library of the Contra Costa County Library enjoys one of the highest circulation per capita rates of any Contra Costa County Library. Kensington Hilltop Elementary School serves to educate Kindergarten to 6th grade. Kensington is served by the West Contra Costa Unified School District. Children may also attend private schools in other nearby cities such as Berkeley.


According to the United States Census Bureau, the CDP has a total area of 1.0 square mile (2.6 km2), of which, 99% is land 1% is water.
Kensington borders Berkeley and Albany to the south, El Cerrito to its west and north, and Wildcat Canyon Regional Park and Tilden Regional Park to the east.
Kensington is largely residential, with two small shopping districts. One of these is located on Arlington Avenue, the other centered on the Colusa Circle.