California's 10th congressional district (CA-10)
California's 10th congressional district (CA-10) covers parts or all of Contra Costa County and Alameda County, and 44 ZIP codes (23 wholly inside it). Its 2020 population was 759,118. This is the map in force for the November 3, 2026 election.
Who represents CA-10
| Office | Member | Contact |
|---|---|---|
| U.S. Representative (CA-10) | Mark DeSaulnier (D) | 202-225-2095 |
| 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-10 |
|---|---|
| Contra Costa County | 58% |
| Alameda County | 4.7% |
ZIP codes
Percentages mark ZIPs only partly in CA-10: the share of that ZIP's residents inside it.
- 94505 (100%)
- 94506
- 94507
- 94509 (<0.1%)
- 94513 (100%)
- 94514 (95%)
- 94516
- 94517
- 94518
- 94519
- 94520
- 94521
- 94523
- 94525 (61%)
- 94526
- 94528
- 94531 (<0.1%)
- 94541 (3.2%)
- 94546 (76%)
- 94548
- 94549
- 94551 (0.6%)
- 94552 (73%)
- 94553
- 94556
- 94561 (55%)
- 94563 (100%)
- 94565 (24%)
- 94568 (<0.1%)
- 94569
- 94572 (<0.1%)
- 94575
- 94577 (5.3%)
- 94578 (50%)
- 94580 (26%)
- 94582
- 94583
- 94588 (1.3%)
- 94595
- 94596
- 94597
- 94598
- 94611 (<0.1%)
- 94619 (0.2%)
Towns
Central Contra Costa CCD, East Contra Costa CCD, Tassajara CCD, Briones CCD, Hayward CCD, Antioch-Pittsburg CCD and West Contra Costa CCD.
Get this in your AI agent
Your agent can draw every precinct in CA-10, 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:0610", children_level="precinct", include_districts=True)