| ZIP Codes: | 69 ZIP Codes (49 Standard, 14 PO Box, 6 Unique) [See All] |
| Area Codes: | 341 / 408 / 415 / 510 / 628 / 650 / 669 / 925 |
| Timezone: | Pacific (GMT -08:00) |
| Local Time: | 2:11:27 PM |
| Population: | 1,655,008 [See All] |
| FIPS: | 06001 |
| CBSA: | San Francisco-Oakland-Fremont, CA |
| Land Area: | 878 sq mi |
| Water Area: | 20 sq mi |
| Coordinates: | 37.7490, -122.1597 |
| Quick Link: |
1,655,008 residents live across 69 ZIPs covering 878 sq mi, served by 17 distinct USPS-recognized cities.
Population moved from 1,564,884 to 1,655,008 from 2014 to 2024 — a +5.8% change. 38 ZIPs gained residents, 11 lost.
The county's wealthiest ZIP 94539 (Fremont, $243,552 median) and poorest ZIP 94704 (Berkeley, $50,129) are 29.7 miles apart — a 4.9× income gap across local geography.
Median home values vary 3.9× across this county — from $507,800 in 94720 (Berkeley) to $1,992,800 in 94705 (Berkeley).
Density varies 156× across the county — from 150 people/sq mi in 94550 (Livermore) to 23,467 in 94704 (Berkeley).
Educational attainment ranges from 13.5% bachelor's+ in 94621 (Oakland) to 87.5% in 94708 (Berkeley) — the breadth of educational profiles across the area.
Within California, this is the #7 most populous of 58 counties and ranks #6 for median household income with the #21 fastest decade growth .
On the national stage, Alameda County is the #20 most populous US county , ranks #38 for income .
Hosts 4 single-entity Unique ZIPs: 94720Uc Berkeley ; 94666Kaiser Services ; 94649Oakland ; and 94659Blue Cross .
Weighted by population, the typical household earns about $137,397 across the county — reflecting what a typical resident sees, not a simple ZIP average.
52.3% of adults age 25+ hold a bachelor's degree or higher (626,351 of 1,196,579 reporting). The most-educated ZIPs cluster around Berkeley.
49 Standard delivery, 14 PO Box only, 6 single-entity Unique ZIPs serve this county.
22 ZIPs in this county where more than 60% of adults 25+ hold a bachelor's degree — typically college campuses, research enclaves, or tech corridors.
6 ZIP codes in this county serve a single facility — typically theme parks, universities, large corporations, airports, or government complexes.
Median household income spans 4.9× between the wealthiest and poorest ZIPs — a sign of significant intra-county inequality.
| ZIP | City | Type | Population | Median Income | Area (sq mi) | 10-yr Growth |
|---|---|---|---|---|---|---|
| 94544 | Hayward | Standard | 76,947 | $107,785 | 11.1 | 0.6% |
| 94568 | Dublin | Standard | 70,803 | $214,385 | 19.1 | 47.2% |
| 94536 | Fremont | Standard | 70,619 | $167,662 | 14.4 | -0.1% |
| 94538 | Fremont | Standard | 67,781 | $147,301 | 23.0 | 6.2% |
| 94587 | Union City | Standard | 67,464 | $133,715 | 15.6 | -5.9% |
| 94541 | Hayward | Standard | 67,139 | $105,729 | 7.5 | 7.0% |
| 94501 | Alameda | Standard | 63,808 | $127,906 | 8.0 | 2.0% |
| 94601 | Oakland | Standard | 53,259 | $72,359 | 3.2 | 6.5% |
| 94539 | Fremont | Standard | 52,396 | $243,552 | 33.6 | 1.8% |
| 94550 | Livermore | Standard | 49,873 | $180,295 | 332.4 | 3.8% |
| 94560 | Newark | Standard | 46,903 | $169,064 | 14.0 | 7.5% |
| 94577 | San Leandro | Standard | 46,317 | $108,772 | 8.1 | 1.1% |
| 94546 | Castro Valley | Standard | 44,855 | $128,385 | 13.6 | 3.2% |
| 94566 | Pleasanton | Standard | 44,222 | $191,155 | 20.5 | 4.0% |
| 94605 | Oakland | Standard | 44,103 | $106,068 | 9.5 | 2.2% |
| 94578 | San Leandro | Standard | 41,769 | $94,084 | 4.2 | 8.1% |
| 94611 | Oakland | Standard | 40,116 | $180,549 | 8.5 | 7.8% |
| 94606 | Oakland | Standard | 39,966 | $72,470 | 2.3 | 8.0% |
| 94551 | Livermore | Standard | 37,885 | $145,392 | 104.6 | -4.8% |
| 94555 | Fremont | Standard | 37,501 | $219,938 | 18.7 | 5.2% |
| 94603 | Oakland | Standard | 35,742 | $76,723 | 2.7 | 10.6% |
| 94608 | Emeryville | Standard | 34,395 | $120,239 | 2.8 | 30.7% |
| 94588 | Pleasanton | Standard | 34,328 | $191,073 | 17.4 | 7.6% |
| 94621 | Oakland | Standard | 33,840 | $52,049 | 7.7 | 4.9% |
| 94545 | Hayward | Standard | 32,843 | $114,356 | 20.5 | 6.2% |
| 94610 | Oakland | Standard | 32,628 | $134,507 | 2.4 | 9.7% |
| 94602 | Oakland | Standard | 31,759 | $122,263 | 3.6 | 6.6% |
| 94580 | San Lorenzo | Standard | 29,420 | $110,729 | 3.3 | 0.4% |
| 94607 | Oakland | Standard | 28,804 | $94,863 | 6.0 | 16.0% |
| 94619 | Oakland | Standard | 26,831 | $129,867 | 7.9 | 11.1% |
| 94609 | Oakland | Standard | 23,928 | $107,834 | 1.7 | 8.5% |
| 94704 | Berkeley | Standard | 23,788 | $50,129 | 1.0 | -9.7% |
| 94703 | Berkeley | Standard | 20,934 | $109,881 | 1.3 | -2.3% |
| 94579 | San Leandro | Standard | 20,017 | $99,040 | 3.1 | -8.4% |
| 94706 | Albany | Standard | 19,969 | $143,398 | 1.4 | -1.2% |
| 94612 | Oakland | Standard | 18,175 | $74,037 | 0.8 | 25.3% |
| 94702 | Berkeley | Standard | 17,635 | $99,775 | 1.3 | 4.5% |
| 94618 | Oakland | Standard | 16,958 | $201,780 | 2.4 | -0.3% |
| 94542 | Hayward | Standard | 14,871 | $133,734 | 8.9 | 19.0% |
| 94552 | Castro Valley | Standard | 14,506 | $212,605 | 49.7 | -4.6% |
| 94705 | Berkeley | Standard | 13,991 | $167,970 | 2.6 | 9.4% |
| 94502 | Alameda | Standard | 13,430 | $180,938 | 3.4 | 1.8% |
| 94707 | Berkeley | Standard | 12,811 | $212,776 | 1.8 | 3.3% |
| 94709 | Berkeley | Standard | 12,146 | $89,054 | 0.6 | 1.0% |
| 94708 | Berkeley | Standard | 11,947 | $234,923 | 4.0 | 7.2% |
| 94710 | Berkeley | Standard | 8,380 | $102,227 | 2.6 | 30.1% |
| 94720 | Berkeley | Unique | 5,763 | — | 1.5 | 88.4% |
| 94586 | Sunol | Standard | 971 | $204,931 | 42.7 | -1.3% |
| 94613 | Oakland | PO Box | 472 | — | 0.2 | -43.9% |
| 94624 | Oakland | PO Box | — | — | 0.0 | — |
| 94614 | Oakland | PO Box | — | — | 0.0 | — |
| 94543 | Hayward | PO Box | — | — | 0.0 | — |
| 94557 | Hayward | PO Box | — | — | 0.0 | — |
| 94537 | Fremont | PO Box | — | — | 0.0 | — |
| 94540 | Hayward | PO Box | — | — | 0.0 | — |
| 94662 | Emeryville | PO Box | — | — | 0.0 | — |
| 94701 | Berkeley | PO Box | — | — | 0.0 | — |
| 94712 | Berkeley | PO Box | — | — | 0.0 | — |
| 94666 | Oakland | Unique | — | — | 0.0 | — |
| 94620 | Piedmont | PO Box | — | — | 0.0 | — |
| 94661 | Oakland | PO Box | — | — | 0.0 | — |
| 94604 | Oakland | PO Box | — | — | 0.0 | — |
| 94623 | Oakland | PO Box | — | — | 0.0 | — |
| 94615 | Oakland | Standard | — | — | 0.1 | — |
| 94649 | Oakland | Unique | — | — | 0.0 | — |
| 94617 | Oakland | Standard | — | — | 0.0 | — |
| 94659 | Oakland | Unique | — | — | 0.0 | — |
| 94660 | Oakland | Unique | — | — | 0.0 | — |
| 94622 | Oakland | Unique | — | — | 0.0 | — |