San Joaquin County, California

San Joaquin County is a county in California, United States, about 65 miles east of San
Francisco and 40 miles south of Sacramento. It had a population of 779,233 at the 2020 census, an
estimated 823,815 by 2025, and covers 1,391 square miles (3,600 km2) centred near 37°54′N 121°12′W.

Stockton is the county seat and the county’s largest city; its postal code is 95202. The
county holds 8 cities and about two dozen unincorporated communities and census-designated places
— California has no civil townships — and it runs on Pacific Time. Its FIPS code is
06077.

Towns & Villages in San Joaquin County

San Joaquin County has 34 named places on record: 8 incorporated cities and 26 unincorporated
communities and census-designated places (CDPs) with no city government of their own. CDP stands
for census designated place; Unincorp. covers a community with no formal boundary or, in a few
cases, no population figure on record.

Mountain House is the county’s newest city, incorporated on July 1, 2024, after two
decades as one of California’s fastest-growing unincorporated communities; its table row
uses its 2020 census figure from before incorporation.

ZIP Codes

• 95202 — downtown Stockton, county government offices
• 95376 — central Tracy
• 95336 — central Manteca
• 95240 — central Lodi
• 95330 — Lathrop
• 95391 — Mountain House
• 95366 — Ripon
• 95320 — Escalon
• 95231 — French Camp
• 95237 — Lockeford
• 95258 — Woodbridge
• 95236 — Linden
• 95220 — Acampo
• 95227 — Clements
• 95242 — Terminous, sharing a ZIP with part of Lodi
• 95253 — Victor
• 95230 — Farmington
• 95686 — Thornton
• 95385 — Vernalis

Kennedy, Collierville, Waterloo, August, Dogtown, Peters, Taft Mosswood, Atlanta, Banta,
Mormon and Youngstown have no ZIP code of their own; mail there is addressed through a
neighbouring town’s post office.

Geography

San Joaquin County sits in the northern San Joaquin Valley, at the southern edge of the
Sacramento–San Joaquin River Delta, where the San Joaquin, Mokelumne and Calaveras rivers
converge into a maze of sloughs and reclaimed islands. The eastern third of the county is flat
farmland rising gently toward the Sierra Nevada foothills; the delta islands in the northwest sit
below sea level behind levees.

The county borders Sacramento
County to the north, Amador
County to the northeast, Calaveras
County to the east, Stanislaus
County to the south, Santa Clara
County to the southwest, Alameda
County to the west and Contra
Costa County to the northwest.

Demographics

San Joaquin County had 779,233 residents at the 2020 census, an estimated 823,815 by 2025, and
a population density of 560.2 people per square mile. Stockton and Tracy are the two largest
communities, together holding more than half the county’s population. California’s
statewide median household income was $95,521 in 2023 (ACS).

Economy & Local Life

Agriculture anchors the county’s economy: farms produced $2.6 billion in gross value in
2018, led by almonds, wine grapes, milk and walnuts. Stockton’s port and warehousing
sector employs thousands, with Amazon (about 6,040 workers), Stockton Unified School District
(about 5,615) and St. Joseph’s Medical Center (about 3,200) among the city’s largest
employers; Archer Daniels Midland, Blue Shield of California and Kubota Tractors also run major
operations in the county. University of the Pacific and San Joaquin Delta College, both in
Stockton, anchor higher education. The Stockton Asparagus Festival runs every April, and the
Lodi Grape Festival, celebrating the Lodi wine-growing region, runs every September.

History

San Joaquin County was one of California’s original 27 counties, created in 1850 at
statehood. It takes its name from the San Joaquin River, which Lieutenant Gabriel Moraga named
for St. Joachim during an early-19th-century expedition. The Gold Rush turned Stockton into an
inland port and supply hub for miners heading to the Sierra Nevada mother lode; by the 1870s the
county had shifted to the large-scale agriculture that still defines it. In June 2012, Stockton
became the largest U.S. city at that time to file for municipal bankruptcy protection.

Getting There

Interstate 5 crosses the county’s west side and Interstate 205 links it to Interstate 580
near Tracy; State Route 99 runs the length of the county through Stockton, Lodi and Manteca.
Anchor distances from Stockton:

• Sacramento — 40 miles north
• Oakland — 70 miles west
• San Jose — 75 miles southwest
• Modesto — 30 miles south

Stockton Metropolitan Airport handles regional and cargo flights; Sacramento International and
Oakland International are the nearest major hubs. Amtrak’s San Joaquins line stops in
Stockton and Lodi, and the Altamont Corridor Express (ACE) commuter train links Stockton, Lathrop
and Tracy to the Bay Area on weekdays.

Frequently Asked Questions

Where is San Joaquin County located?
It is in California’s northern San Joaquin Valley, about 65 miles east of San Francisco and
40 miles south of Sacramento.

What is the population of San Joaquin County?
779,233 at the 2020 census, estimated at 823,815 by 2025.

How big is San Joaquin County?
The county covers 1,391 square miles (3,600 km2) of land.

What is the county seat of San Joaquin County?
Stockton is the county seat and the county’s largest city.

How many towns are in San Joaquin County?
The county has 8 incorporated cities and 26 unincorporated communities and CDPs, listed above.

What ZIP codes serve San Joaquin County?
Codes range from 95202 in downtown Stockton to 95686 in Thornton; see the ZIP Codes section for
the full list.

Is Mountain House a city?
Yes. Mountain House incorporated on July 1, 2024, after growing as an unincorporated master-planned
community since the 1990s.

More counties in this state: Towns
and villages in California.