Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — CITY/CA/FOSTER-CITY

Foster City ZIP codes, California

No ZIP code is named for Foster City, CA; addresses there use a neighbouring town's name. The ZIP code covering it is 94404. Its area code is 650.

USPS city name
0 ZIP codes
Overlapping the city
1 more
Population
32,792
Area code
650

NANPA lists no telephone rate centre for Foster City itself, so these are the area codes of the nearest one, San Mateo (0.0 miles). A town on an area-code boundary can differ from its neighbour.

Foster City in numbers

About 32,792 people live in Foster City, in 12,998 households. The median household income is $199,143 a year, 2.0 times the California median of $99,122 (US: $80,734). The median owner-occupied home is valued at $1,838,200 (2.5 times the California median), and median gross rent is $3,500+ a month. The median age is 39.5; 73.8% of adults 25 and over hold a bachelor's degree or higher (37.1% across California); the average commute takes 29 minutes.

Population32,792Foster City32,792
Households12,998Foster City12,998
Median age39.5Foster City39.5California37.9US 38.9
Median household income$199,143Foster City$199,143California$99,122US $80,734
Median home value$1,838,200Foster City$1,838,200California$734,700US $332,700
Median gross rent$3,500+Foster City$3,500+California$2,036US $1,413
Bachelor's degree or higher73.8%Foster City73.8%California37.1%US 35.7%
Mean commute29.4 minFoster City29.4 minCalifornia28.7 minUS 26.4 min
Population density8,659 / sq miFoster City8,659 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place Foster City city. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes covering Foster City

These ZIP codes cover part of Foster City but are addressed as somewhere else.

ZIP codes overlapping Foster City
ZIP City Type Population Median income Median home
94404 San Mateo , CA Standard 35,881 $192,332 $1,714,400

Map of Foster City ZIP codes

94404

The ZIP codes of Foster City, CA, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Foster City

The nearest larger towns are San Mateo (103,105 people, 3.3 mi), Redwood City (82,447 people, 4.0 mi) and Hayward (158,801 people, 9.1 mi).

Towns near Foster City
TownPopulationDistance
San Mateo 103,105 3.3 mi
Redwood City 82,447 4.0 mi
Belmont 27,337 4.2 mi
San Carlos 29,614 4.6 mi
Hillsborough 11,099 5.9 mi
Burlingame 30,525 6.4 mi
North Fair Oaks 13,100 6.7 mi
Emerald Lake Hills 4,235 6.9 mi
Atherton 6,993 7.9 mi
Menlo Park 32,727 8.1 mi
Millbrae 22,689 8.6 mi
Hayward 158,801 9.1 mi
South San Francisco 64,305 9.3 mi
East Palo Alto 29,069 9.3 mi

More nearby: every ZIP code in San Mateo County · California ZIP codes

Cite this page

zipcodes.pro. “Foster City, CA ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ca/foster-city

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