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zipcodes.pro — CITY/CA/CASTRO-VALLEY

Castro Valley ZIP codes, California

Castro Valley, CA has 2 ZIP codes: 94546 and 94552. The largest is 94546.

USPS city name
2 ZIP codes
Overlapping the city
3 more
Population
65,001

Mail addressed to Castro Valley uses the ZIP codes above. 3 more ZIP codes cover part of the city but are addressed as somewhere else; they are listed separately below.

Castro Valley in numbers

About 65,001 people live in Castro Valley, in 22,021 households. The median household income is $142,779 a year, 44% above the California median of $99,122 (US: $80,734). The median owner-occupied home is valued at $1,104,600 (50% above the California median), and median gross rent is $2,554 a month. The median age is 42.9; 44.5% of adults 25 and over hold a bachelor's degree or higher (37.1% across California); the average commute takes 33 minutes.

Population65,001Castro Valley65,001
Households22,021Castro Valley22,021
Median age42.9Castro Valley42.9California37.9US 38.9
Median household income$142,779Castro Valley$142,779California$99,122US $80,734
Median home value$1,104,600Castro Valley$1,104,600California$734,700US $332,700
Median gross rent$2,554Castro Valley$2,554California$2,036US $1,413
Bachelor's degree or higher44.5%Castro Valley44.5%California37.1%US 35.7%
Mean commute32.7 minCastro Valley32.7 minCalifornia28.7 minUS 26.4 min
Population density3,858 / sq miCastro Valley3,858 / sq mi

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

ZIP codes addressed as Castro Valley

ZIP codes with the USPS city name Castro Valley
ZIP City Type Population Median income Median home
94546 Castro Valley , CA Standard 44,855 $128,385 $1,043,500
94552 Castro Valley , CA Standard 14,506 $212,605 $1,394,300

Other ZIP codes overlapping Castro Valley

These ZIP codes cover part of Castro Valley but are addressed as somewhere else.

ZIP codes overlapping Castro Valley
ZIP City Type Population Median income Median home
94541 Hayward , CA Standard 67,139 $105,729 $812,000
94577 San Leandro , CA Standard 46,317 $108,772 $856,100
94578 San Leandro , CA Standard 41,769 $94,084 $823,000

Map of Castro Valley ZIP codes

9454694552

The ZIP codes of Castro Valley, 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 Castro Valley

The nearest larger towns are San Leandro (87,826 people, 5.5 mi), Hayward (158,801 people, 6.1 mi) and Union City (67,464 people, 7.7 mi).

Towns near Castro Valley
TownPopulationDistance
Fairview 10,745 2.3 mi
Cherryland 14,143 3.0 mi
Ashland 22,210 3.1 mi
San Lorenzo 29,171 4.6 mi
San Leandro 87,826 5.5 mi
Hayward 158,801 6.1 mi
Union City 67,464 7.7 mi
San Ramon 85,993 8.2 mi
Danville 43,401 8.8 mi
Dublin 70,803 9.1 mi
Oakland 439,418 9.9 mi
Moraga 16,769 10.1 mi
Pleasanton 76,960 10.3 mi
Alamo 14,488 10.5 mi

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

Cite this page

zipcodes.pro. “Castro Valley, CA ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ca/castro-valley

Underlying data is public domain or openly licensed — sources, vintages and licences.