Boundary Atlas

ZIP code 94546: Castro Valley, CA

ZIP code 94546 is in Castro Valley (98% of residents) and Hayward (2.3%), in Alameda County, California. It is in California's 10th congressional district (76%) and California's 14th congressional district (24%). Its state senate districts are State Senate District 9 (98%) and State Senate District 10 (2.3%); its state house districts are Assembly District 20 (100%), Assembly District 16 (<0.1%) and Assembly District 18 (<0.1%).

46,687residents (2020 Census)
16.0 sq miland area
2cities and towns
2congressional districts
24voting precincts

See it on the mapAll of California

City and county

City or townShare of ZIP residents
Castro Valley98%
Hayward2.3%

CountyShare of ZIP residents
Alameda County100%

Town or county subdivisionShare of ZIP residents
Hayward CCD100%

Congressional districts

Congressional districtShare of ZIP residents
California's 10th congressional district (CA-10)76%
California's 14th congressional district (CA-14)24%

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)202-225-209576%
U.S. Representative (CA-14)Aisha Wahab (D)202-225-506524%
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)925-258-117698%
Assembly Member (Assembly District 20)Liz Ortega (Democratic)510-583-8818100%
Assembly Member (Assembly District 16)Rebecca Bauer-Kahan (Democratic)925-244-1600<0.1%
Assembly Member (Assembly District 18)Mia Bonta (Democratic)510-286-1670<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 998%
State Senate District 102.3%

State house districtShare of ZIP residents
Assembly District 20100%
Assembly District 16<0.1%
Assembly District 18<0.1%

Voting precincts

24 voting precincts overlap ZIP 94546. Map them, with each precinct's share of the ZIP's residents.

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related_geographies(id="us:zcta:94546")

ZIP 94546 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.