What is the largest city in Alameda County, CA?

Oakland is the largest city or town in Alameda County, with about 439,418 residents.

How many ZIP codes are in Alameda County?

Alameda County includes 48 ZIP Code Tabulation Areas, including 94501, 94502, 94536, 94538, 94539.

What is the population of Alameda County, CA?

About 1,649,473 people live in Alameda County, based on American Community Survey 5-year estimates.

What counties border Alameda County?

Alameda County borders Santa Clara County, Contra Costa County, San Francisco County, San Joaquin County, Stanislaus County.

Alameda County, CA: Cities, ZIP Codes & Local Data

Population

1,649,473

Land area

737sq mi

People per sq mi

2,237

ZIP codes

48

Alameda County at a glance

Alameda County is about 8.9 times as dense as California as a whole.
It is the 7th most populous of 58 counties in California.
Households here earn a median of $129,367 a year, 31% more than the California figure of $99,122.
A typical owner-occupied home is valued at $1,090,100 (48% above California) and median rent is $2,357 a month.
The biggest population centers are Oakland (439,418), Fremont (228,295) and Hayward (158,801).

Local data for Alameda County, CA

Counts from official public data

Housing and community stats

Alameda County, CA, American Community Survey 2020-2024

Full profile

Median household income

$129,367

Poverty rate

9.2%

Median home value

$1,090,100

Prices -1.9% in a year

Median rent

$2,357/mo

Homeownership

54.4%

Bachelor's or higher

52.2%

Median age

39.0

Average commute

31.0 min

Largest reported origins and ancestries: Mexican Americans (267,768), Chinese Americans (174,267), Indian Americans (154,093).

Home values and rents Income, education and commute

Economy and federal money

Jobs, income, federal spending and pandemic loans

Details

Unemployment rate

4.7%

Sep 2026, -0.2 pts in a year

Average annual pay

$101,979

783,094 jobs, 2025

Income per person

$111,268

BEA, 2024

Federal spending

$42.4B

FY 2026, $25,202 per person

PPP loans

$5.3B

55,318 loans, 501,236 jobs reported

Campaign donations

$44M

Itemized, 2026 cycle

Economy Federal spending PPP loans

How people get to work

Alameda County, CA, workers 16 and older. American Community Survey 5-year estimates

Drove alone52.6%
Carpooled8.3%
Public transit7.7%
Walked2.8%
Bicycle1.2%
Taxi, ride-hailing, motorcycle or other1.7%
Worked from home25.7%

Average one-way commute: 31.0 minutes for people who do not work from home.

Environment and hazard risk

Alameda County, CA, from FEMA, NOAA and EPA

Full report

Natural hazard risk

Very High

Top: earthquake

Storm events since 1996

603

Most often strong wind

Flood insurance policies

3,420

0.8% of homes, county

July high / Jan low

89° / 39°F

14.6 inches of rain a year

Hazards, floods and storm history Check a flood zone 137 historic places

Health statistics

Share of adults in Alameda County, CA, CDC PLACES estimates

All 40 measures

Obesity

22.8%

U.S. 33.3% -10.5 pts

Diabetes

11.0%

U.S. 12.1% -1.1 pts

Smoking

9.3%

U.S. 12.8% -3.5 pts

Uninsured (18-64)

7.1%

U.S. 11.1% -4.0 pts

Cities, towns and ZIP codes in Alameda County

Population shown

Frequently asked questions

What is the largest city in Alameda County, CA?: Oakland is the largest city or town in Alameda County, with about 439,418 residents.
How many ZIP codes are in Alameda County?: Alameda County includes 48 ZIP Code Tabulation Areas, including 94501, 94502, 94536, 94538, 94539.
What is the population of Alameda County, CA?: About 1,649,473 people live in Alameda County, based on American Community Survey 5-year estimates.
What counties border Alameda County?: Alameda County borders Santa Clara County, Contra Costa County, San Francisco County, San Joaquin County, Stanislaus County.