Boundary Atlas

ZIP code 91740: Glendora, CA

ZIP code 91740 is in Glendora (97% of residents) and San Dimas (1.5%), in Los Angeles County, California. It is in California's 31st congressional district. Its state senate districts are State Senate District 25 (97%) and State Senate District 22 (3.0%); its state house districts are Assembly District 48 (99%) and Assembly District 41 (1.5%).

26,644residents (2020 Census)
5.0 sq miland area
4cities and towns
1congressional district
19voting precincts

See it on the mapAll of California

City and county

City or townShare of ZIP residents
Glendora97%
San Dimas1.5%
Citrus0.9%
Charter Oak0.3%

CountyShare of ZIP residents
Los Angeles County100%

Town or county subdivisionShare of ZIP residents
East San Gabriel Valley CCD100%

Congressional district

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

Elected officials

OfficeMemberContactShare of residents
MayorMendell Thompson97%
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 25)Sasha Pérez (Democratic)818-409-040297%
State Senator (State Senate District 22)Susan Rubio (Democratic)909-460-60643.0%
Assembly Member (Assembly District 48)Blanca Rubio (Democratic)626-960-445799%
Assembly Member (Assembly District 41)John Harabedian (Democratic)626-351-19171.5%

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 2597%
State Senate District 223.0%

State house districtShare of ZIP residents
Assembly District 4899%
Assembly District 411.5%

Voting precincts

19 voting precincts overlap ZIP 91740. Map them, with each precinct's share of the ZIP's residents.

Get this in your AI agent

Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

related_geographies(id="us:zcta:91740")

ZIP 91740 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.