Alameda County, California
Alameda County, California, has 1,636,630 residents (July 2025 estimate). Its county seat is Oakland. It uses Pacific Time and covers 737 sq mi (1,910 km²) of land.
- Resident population, July 2025
- 1,636,630
- Land area
- 737 sq mi (1,910 km²)
- County seat or government
- Oakland
- Time zone
- Pacific TimeUTC-08:00 in January; UTC-07:00 in July
- Median household income
- $129,367 ± $1,284
- Median home value
- $1,090,100 ± $6,313
- Median rent, with utilities
- $2,357 ± $16
- Homes lived in by their owners
- 54.4% ± 0.5 points
- County type
- County
- Metro or micro area
- San Francisco-Oakland-Fremont, CA metro areaCentral county
- Water area
- 83.7 sq mi (217 km²)
- State
- California
- County code (FIPS)
- 06001
- Coordinates (central point)
- 37.647139, -121.912488
These coordinates mark a central point for the area, not a street address. Income, home value, rent and homes lived in by their owners: U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, ± margin at 90% confidence; checked on October 13, 2026.
Time zones in Alameda County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| Pacific TimeAmerica/Los_Angeles | UTC-08:00 in January; UTC-07:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Near a time-zone line, check where you are with the time-zone finder. Your phone’s setting can differ.
ZIP Code areas, largest first
- 9454476,947 people
- 9456870,803 people
- 9453670,619 people
- 9453867,781 people
- 9458767,464 people
- 9454167,139 people
- 9450163,808 people
- 9460153,259 people
- 9453952,396 people
- 9455049,873 people
- 9456046,903 people
- 9457746,317 people
All 53
- 9454644,855 people
- 9456644,222 people
- 9460544,103 people
- 9457841,769 people
- 9461140,116 people
- 9460639,966 people
- 9455137,885 people
- 9537737,739 people
- 9455537,501 people
- 9460335,742 people
- 9460834,395 people
- 9458834,328 people
- 9462133,840 people
- 9454532,843 people
- 9461032,628 people
- 9460231,759 people
- 9458029,420 people
- 9460728,804 people
- 9461926,831 people
- 9539125,574 people
- 9460923,928 people
- 9470423,788 people
- 9470320,934 people
- 9457920,017 people
- 9470619,969 people
- 9461218,175 people
- 9470217,635 people
- 9461816,958 people
- 9450514,970 people
- 9454214,871 people
- 9455214,506 people
- 9470513,991 people
- 9450213,430 people
- 9470712,811 people
- 9470912,146 people
- 9470811,947 people
- 947108,380 people
- 947205,763 people
- 945141,953 people
- 94586971 people
- 94613472 people
53 ZIP Code areas overlap Alameda County. People counts are 2020–2024 estimates for each whole ZIP area. Mailing ZIPs can differ; check an address with USPS ZIP Code Lookup.
Official county information
Alameda County government website ↗ is the next stop for county offices, tax, voting, jury and records information. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
School districts in Alameda County, largest first
- Oakland Unified School District438,372 people
- Fremont Unified School District228,295 people
- Hayward Unified School District180,228 people
- Berkeley Unified School District120,257 people
- Livermore Valley Joint Unified School District88,347 people
- San Lorenzo Unified School District80,925 people
- Pleasanton Unified School District77,430 people
- Alameda City Unified School District77,238 people
- San Leandro Unified School District72,233 people
- New Haven Unified School District72,055 people
- Dublin Unified School District70,803 people
- Castro Valley Unified School District51,914 people
All 19
- Newark Unified School District46,903 people
- Albany City Unified School District19,414 people
- Emery Unified School District13,081 people
- Piedmont City Unified School District10,830 people
- Sunol Glen Unified School District983 people
- Lammersville Joint Unified School District (9-12)275 people
- Mountain House Elementary School District275 people
Districts with land in the county; a district can cross county lines. People counts are American Community Survey 2020–2024 5-year estimates. A district boundary doesn’t decide which school a student attends.
Cities, towns and communities, largest first
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
- Oakland, California (city)439,418 people
- Fremont, California (city)228,295 people
- Hayward, California (city)158,801 people
- Berkeley, California (city)120,257 people
- San Leandro, California (city)87,826 people
- Livermore, California (city)85,522 people
- Alameda, California (city)77,238 people
- Pleasanton, California (city)76,960 people
- Dublin, California (city)70,803 people
- Union City, California (city)67,464 people
- Castro Valley, California (CDP)65,001 people
- Newark, California (city)46,903 people
All 20
- San Lorenzo, California (CDP)29,171 people
- Ashland, California (CDP)22,210 people
- Albany, California (city)19,414 people
- Cherryland, California (CDP)14,143 people
- Emeryville, California (city)13,081 people
- Piedmont, California (city)10,945 people
- Fairview, California (CDP)10,745 people
- Sunol, California (CDP)847 people
Bordering areas, nearest first
Distances are straight lines between map points.
- Contra Costa County, California19 mi north
- San Mateo County, California30 mi southwest
- Santa Clara County, California32 mi southeast
- San Joaquin County, California40 mi northeast
- Stanislaus County, California50 mi east
- San Francisco County, California61 mi west
Before using this answer on a form
Use a precise point for address-level questions. A device accuracy circle can cross a boundary; confirm tax, voting or jury details with the responsible office.
Find the county where you are now, check its ZIP area, or check the time zone where you are.
Areas that only touch the edge
These areas meet the boundary only along a sliver. Most addresses here are not in them; for an address near the line, check with the county.