County ZIP codes · California · FIPS 06013
Contra Costa County, CA ZIP Codes
Contra Costa County, California has 58 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 48 residential and 10 for PO boxes or a single organization. 43 of the residential ones lie mainly in Contra Costa County and 5 mainly in a neighboring county; 8 cross the county line. Median household income ranges from $81,728 in 94801 (Richmond) to $250,000 or more in 3 ZIP codes at the Census top code (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
Where are the ZIP codes of Contra Costa County?
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).
How different are its ZIP codes?
The middle half of its ranked ZIP codes (1,000+ people living in households) report median household incomes between $111,152 and $168,921. 3 report $250,000 or more, the Census top code.
They carry 35 postal town names.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).
All 48 residential ZIP codes in Contra Costa County
43 ZIP codes lie mainly in Contra Costa County; 5 more reach into it from a neighboring county and follow the first table.
| In this county | ||||||
|---|---|---|---|---|---|---|
| 94565 | Pittsburg | 100,488 | 2,219 | $96k | $584k | 100% |
| 94509 | Antioch | 70,090 | 4,018 | $86k | $584k | 100% |
| 94513 | Brentwood | 69,755 | 885 | $142k | $838k | 100% |
| 94806 | San Pablo | 62,546 | 7,966 | $86k | $608k | 100% |
| 94553 | Martinez | 48,643 | 789 | $124k | $826k | 100% |
| 94582 | San Ramon | 47,424 | 3,536 | $215k | $1.64M | 100% |
| 94531 | Antioch | 46,387 | 3,307 | $121k | $702k | 100% |
| 94561 | Oakley | 46,368 | 2,674 | $135k | $660k | 100% |
| 94804 | Richmond | 44,891 | 6,914 | $91k | $632k | 100% |
| 94521 | Concord | 41,909 | 4,328 | $126k | $853k | 100% |
| 94583 | San Ramon | 39,583 | 1,864 | $185k | $1.38M | 100% |
| 94520 | Concord | 37,381 | 3,787 | $83k | $601k | 100% |
| 94523 | Pleasant Hill | 34,592 | 4,800 | $143k | $1.08M | 100% |
| 94801 | Richmond | 33,591 | 2,920 | $82k | $609k | 100% |
| 94526 | Danville | 32,584 | 2,474 | $225k | $1.68M | 100% |
| 94549 | Lafayette | 28,420 | 1,432 | $235k | $2M+ | 100% |
| 94803 | El Sobrante | 27,659 | 2,158 | $118k | $784k | 100% |
| 94518 | Concord | 27,345 | 4,935 | $112k | $859k | 100% |
| 94598 | Walnut Creek | 27,206 | 1,320 | $186k | $1.34M | 100% |
| 94506 | Danville | 27,055 | 1,450 | $250k+ | $1.96M | 100% |
| 94530 | El Cerrito | 26,401 | 6,097 | $129k | $1.11M | 100% |
| 94547 | Hercules | 26,302 | 4,639 | $129k | $769k | 100% |
| 94596 | Walnut Creek | 23,417 | 3,863 | $136k | $1.28M | 100% |
| 94597 | Walnut Creek | 23,129 | 5,707 | $132k | $1.03M | 100% |
| 94563 | Orinda | 19,378 | 944 | $250k+ | $1.87M | 100% |
| 94519 | Concord | 19,058 | 4,201 | $122k | $784k | 100% |
| 94564 | Pinole | 18,761 | 2,747 | $128k | $719k | 100% |
| 94595 | Walnut Creek | 16,988 | 3,256 | $101k | $861k | 100% |
| 94556 | Moraga | 15,998 | 830 | $216k | $1.66M | 100% |
| 94505 | Discovery Bay | 14,970 | 898 | $147k | $831k | 96% |
| 94805 | Richmond | 14,670 | 7,866 | $111k | $792k | 100% |
| 94507 | Alamo | 14,586 | 1,303 | $250k+ | $2M+ | 100% |
| 94517 | Clayton | 12,316 | 258 | $169k | $1.03M | 100% |
| 94708 | Berkeley | 11,947 | 3,588 | $235k | $1.59M | 58% |
| 94572 | Rodeo | 8,976 | 978 | $92k | $663k | 100% |
| 94525 | Crockett | 3,372 | 1,375 | $111k | $776k | 100% |
| 94514 | Byron | 1,953 | 65 | $77k | $736k | 82% |
| 94511 | Bethel Island | 1,864 | 355 | $75k | $683k | 100% |
| 94528 | Diablo | 1,049 | 909 | $208k | $2M+ | 100% |
| 94575 | Moraga | 975 | 6,056 | – | – | 100% |
| 94548 | Knightsen | 832 | 360 | $190k | $960k | 100% |
| 94569 | Port Costa | 296 | 230 | $39k | $600k | 100% |
| 94516 | Canyon | 214 | 59 | $113k | $785k | 100% |
Partly in Contra Costa County
| In this county | ||||||
|---|---|---|---|---|---|---|
| 94588 | Pleasanton | 34,328 | 1,049 | $191k | $1.38M | 49% |
| 94551 | Livermore | 37,885 | 458 | $145k | $979k | 37% |
| 94707 | Berkeley | 12,811 | 7,271 | $213k | $1.65M | 35% |
| 95219 | Stockton | 31,713 | 271 | $112k | $581k | 16% |
| 94611 | Oakland | 40,116 | 5,495 | $181k | $1.54M | 5% |
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).
Which ZIP codes cross the county line?
8 ZIP codes of Contra Costa County extend into another county. A ZIP code follows mail routes, not county borders.
| ZIP | In Contra Costa | Elsewhere |
|---|---|---|
| 94611 | 5% | Alameda County 95% |
| 94551 | 37% | Alameda County 63% |
| 94588 | 49% | Alameda County 51% |
| 95219 | 16% | San Joaquin County 84% |
| 94505 | 96% | Alameda County 4% |
| 94707 | 35% | Alameda County 65% |
| 94708 | 58% | Alameda County 42% |
| 94514 | 82% | Alameda County 18% |
Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).
PO Box and single-organization ZIP codes
Source: GeoNames postal codes (CC BY 4.0).
Which first three digits do Contra Costa County's ZIP codes use?
The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Contra Costa County's ZIP codes use 5 prefixes: 945, 946, 947, 948 and 952.
| Prefix | Sectional center | Here | All codes |
|---|---|---|---|
| 945 | Oakland, CA (SCF 945) | 44 | 93 |
| 946 | Oakland, CA (SCF 945) | 1 | 29 |
| 947 | Oakland, CA (SCF 945) | 2 | 12 |
| 948 | Oakland, CA (SCF 945) | 10 | 10 |
| 952 | Sacramento, CA (SCF 956) | 1 | 52 |
Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.