Boundary Atlas

ZIP code 94561: Oakley, CA

ZIP code 94561 is in Oakley (97% of residents), in Contra Costa County, California. It is in California's 10th congressional district (55%) and California's 9th congressional district (45%). Its state senate district is State Senate District 3; its state house district is Assembly District 11.

44,545residents (2020 Census)
17.3 sq miland area
2cities and towns
2congressional districts
47voting precincts

See it on the mapAll of California

City and county

City or townShare of ZIP residents
Oakley97%
Knightsen0.3%

CountyShare of ZIP residents
Contra Costa County100%

Town or county subdivisionShare of ZIP residents
East Contra Costa CCD99%
Antioch-Pittsburg CCD1.1%

Congressional districts

Congressional districtShare of ZIP residents
California's 10th congressional district (CA-10)55%
California's 9th congressional district (CA-09)45%

This ZIP is split between districts. A mailing address in it could be in either; the map or locate_point gives the district for an exact address.

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (CA-10)Mark DeSaulnier (D)202-225-209555%
U.S. Representative (CA-09)Josh Harder (D)202-225-454045%
U.S. SenatorAdam B. Schiff (D)202-224-3841statewide
U.S. SenatorAlex Padilla (D)202-224-3553 · contact formstatewide
State Senator (State Senate District 3)Christopher Cabaldon (Democratic)707-454-3808100%
State Senator (State Senate District 9)Tim Grayson (Democratic)925-258-1176<0.1%
Assembly Member (Assembly District 11)Lori Wilson (Democratic)707-438-7359100%
Assembly Member (Assembly District 15)Anamarie Avila Farias (Democratic)925-521-1511<0.1%

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).

Local government

State legislative districts

State senate districtShare of ZIP residents
State Senate District 3100%
State Senate District 9land only

State house districtShare of ZIP residents
Assembly District 11100%
Assembly District 15land only

Voting precincts

47 voting precincts overlap ZIP 94561. Map them, with each precinct's share of the ZIP's residents.

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ZIP 94561 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.