Boundary Atlas

ZIP code 94521: Concord, CA

ZIP code 94521 is in Concord (98% of residents), in Contra Costa County, California. It is in California's 10th congressional district. Its state senate district is State Senate District 9; its state house districts are Assembly District 15 (100%) and Assembly District 16 (<0.1%).

42,885residents (2020 Census)
9.7 sq miland area
1cities and towns
1congressional district
22voting precincts

See it on the mapAll of California

City and county

City or townShare of ZIP residents
Concord98%

CountyShare of ZIP residents
Contra Costa County100%

Town or county subdivisionShare of ZIP residents
Central Contra Costa CCD99%
Antioch-Pittsburg CCD0.9%
Tassajara CCD<0.1%

Congressional district

Congressional districtShare of ZIP residents
California's 10th congressional district (CA-10)100%

Elected officials

OfficeMemberContactShare of residents
MayorLaura Hoffmeister98%
U.S. Representative (CA-10)Mark DeSaulnier (D)202-225-2095100%
U.S. SenatorAdam B. Schiff (D)202-224-3841statewide
U.S. SenatorAlex Padilla (D)202-224-3553 · contact formstatewide
State Senator (State Senate District 9)Tim Grayson (Democratic)925-258-1176100%
Assembly Member (Assembly District 15)Anamarie Avila Farias (Democratic)925-521-1511100%
Assembly Member (Assembly District 16)Rebecca Bauer-Kahan (Democratic)925-244-1600<0.1%

From Wikidata (community-maintained); confirm on the city's website.

Elected in 2024 under CA's previous congressional map; this district's lines changed for the 120th Congress (seated January 3, 2027).

Officials serving now (members of Congress until January 3, 2027). Sources: State legislators: Open States (public domain); Members of Congress: the @unitedstates project, congress-legislators (CC0); Mayors: Wikidata (CC0).

Local government

State legislative districts

State senate districtShare of ZIP residents
State Senate District 9100%

State house districtShare of ZIP residents
Assembly District 15100%
Assembly District 16<0.1%

Voting precincts

22 voting precincts overlap ZIP 94521. Map them, with each precinct's share of the ZIP's residents.

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ZIP 94521 here is the Census Bureau's ZIP Code Tabulation Area, which approximates the USPS ZIP Code; PO-box-only ZIPs have none. Districts are the maps in force for the November 3, 2026 election.