California's 31st congressional district (CA-31)
California's 31st congressional district (CA-31) covers parts or all of Los Angeles County and San Bernardino County, and 25 ZIP codes (11 wholly inside it). Its 2020 population was 758,733. This is the map in force for the November 3, 2026 election.
Who represents CA-31
| Office | Member | Contact |
|---|---|---|
| U.S. Representative (CA-31) | Gilbert Ray Cisneros, Jr. (D) | 202-225-5256 |
| U.S. Senator | Adam B. Schiff (D) | 202-224-3841 |
| U.S. Senator | Alex Padilla (D) | 202-224-3553 · contact form |
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: Members of Congress: the @unitedstates project, congress-legislators (CC0).
Counties
| County | Share of the county's residents in CA-31 |
|---|---|
| Los Angeles County | 6.3% |
| San Bernardino County | 5.6% |
ZIP codes
Percentages mark ZIPs only partly in CA-31: the share of that ZIP's residents inside it.
- 91006 (11%)
- 91008
- 91010
- 91016
- 91702 (100%)
- 91706 (1.6%)
- 91709 (0.1%)
- 91710 (96%)
- 91722
- 91723
- 91724
- 91740
- 91741
- 91744 (77%)
- 91746 (67%)
- 91750 (98%)
- 91762 (4.6%)
- 91763 (95%)
- 91766 (95%)
- 91768 (30%)
- 91773
- 91789 (71%)
- 91790
- 91791
- 91792 (96%)
Towns
East San Gabriel Valley CCD, Upper San Gabriel Valley CCD and Ontario CCD.
Get this in your AI agent
Your agent can draw every precinct in CA-31, or list them with population shares (related_geographies). Add https://boundarymcp.com/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
get_boundaries(id="us:congressional_district:0631", children_level="precinct", include_districts=True)