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zipcodes.pro — CITY/CA/UNION-CITY

Union City ZIP code, California

The ZIP code for Union City, CA is 94587, and its area codes are 510 and 341.

USPS city name
1 ZIP code
Overlapping the city
5 more
Population
67,464
Area codes
510, 341

NANPA lists no telephone rate centre for Union City itself, so these are the area codes of the nearest one, Hayward (3.2 miles). A town on an area-code boundary can differ from its neighbour.

Mail addressed to Union City uses the ZIP code above. 5 more ZIP codes cover part of the city but are addressed as somewhere else; they are listed separately below.

Union City in numbers

About 67,464 people live in Union City, in 21,240 households. The median household income is $133,715 a year, 35% above the California median of $99,122 (US: $80,734). The median owner-occupied home is valued at $1,104,900 (50% above the California median), and median gross rent is $2,713 a month. The median age is 43.0; 45.1% of adults 25 and over hold a bachelor's degree or higher (37.1% across California); the average commute takes 32 minutes.

Population67,464Union City67,464
Households21,240Union City21,240
Median age43.0Union City43.0California37.9US 38.9
Median household income$133,715Union City$133,715California$99,122US $80,734
Median home value$1,104,900Union City$1,104,900California$734,700US $332,700
Median gross rent$2,713Union City$2,713California$2,036US $1,413
Bachelor's degree or higher45.1%Union City45.1%California37.1%US 35.7%
Mean commute31.9 minUnion City31.9 minCalifornia28.7 minUS 26.4 min
Population density3,478 / sq miUnion City3,478 / sq mi

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

ZIP codes addressed as Union City

ZIP codes with the USPS city name Union City
ZIP City Type Population Median income Median home
94587 Union City , CA Standard 67,464 $133,715 $1,104,900

Other ZIP codes overlapping Union City

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

ZIP codes overlapping Union City
ZIP City Type Population Median income Median home
94542 Hayward , CA Standard 14,871 $133,734 $1,148,000
94544 Hayward , CA Standard 76,947 $107,785 $827,200
94545 Hayward , CA Standard 32,843 $114,356 $879,400
94552 Castro Valley , CA Standard 14,506 $212,605 $1,394,300
94555 Fremont , CA Standard 37,501 $219,938 $1,376,600

Map of Union City ZIP codes

94587

The ZIP codes of Union 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 Union City

The nearest larger towns are Hayward (158,801 people, 4.9 mi), Fremont (228,295 people, 8.6 mi) and Pleasanton (76,960 people, 8.7 mi).

Towns near Union City
TownPopulationDistance
Hayward 158,801 4.9 mi
Fairview 10,745 5.4 mi
Newark 46,903 6.8 mi
Cherryland 14,143 7.0 mi
Castro Valley 65,001 7.7 mi
San Lorenzo 29,171 8.2 mi
Ashland 22,210 8.3 mi
Fremont 228,295 8.6 mi
Pleasanton 76,960 8.7 mi
Dublin 70,803 10.3 mi
San Leandro 87,826 10.5 mi
Menlo Park 32,727 11.1 mi
East Palo Alto 29,069 11.2 mi
San Ramon 85,993 12.2 mi

More nearby: every ZIP code in Alameda County · California ZIP codes

Cite this page

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

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