Boundary Atlas

ZIP code 91773: San Dimas, CA

ZIP code 91773 is in San Dimas, in Los Angeles County, California. It is in California's 31st congressional district. Its state senate district is State Senate District 22; its state house district is Assembly District 41.

34,592residents (2020 Census)
15.0 sq miland area
1cities and towns
1congressional district
13voting precincts

See it on the mapAll of California

City and county

City or townShare of ZIP residents
San Dimas100%

CountyShare of ZIP residents
Los Angeles County100%

Town or county subdivisionShare of ZIP residents
East San Gabriel Valley CCD100%
South Antelope Valley CCDland only

Congressional district

Congressional districtShare of ZIP residents
California's 31st congressional district (CA-31)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (CA-31)Gilbert Ray Cisneros, Jr. (D)202-225-5256100%
U.S. SenatorAdam B. Schiff (D)202-224-3841statewide
U.S. SenatorAlex Padilla (D)202-224-3553 · contact formstatewide
State Senator (State Senate District 22)Susan Rubio (Democratic)909-460-6064100%
Assembly Member (Assembly District 41)John Harabedian (Democratic)626-351-1917100%

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 22100%

State house districtShare of ZIP residents
Assembly District 41100%

Voting precincts

13 voting precincts overlap ZIP 91773. Map them, with each precinct's share of the ZIP's residents.

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ZIP 91773 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.