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zipcodes.pro — ZIP/94531

94531

ZIP 94531 is in Antioch, California, in Contra Costa County; area code 925; Pacific time. Antioch has 2 ZIP codes; the other is 94509.

Type
Standard
Time zone
America/Los_Angeles
County
Contra Costa
Population
46,387
Coordinates
37.9566, -121.7778
☼ Live from 94531 — Antioch, CA

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Local time: —

Where 94531 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 94531
  • 🔢 Type 94531 into a pocket calculator and turn it upside down: IEShG — not quite a word, sorry.
  • ➕ 94531 is a prime number. It cannot be divided by anything except 1 and itself. Its digits add up to 22, a total 2,607 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111000101000011
  • 🏠 Its numerical neighbours: 94530 (El Cerrito, CA, 29 mi away) and 94533 (Fairfield, CA, 26 mi away).
  • 🔄 Backwards, 94531 becomes 13549, which is not a ZIP code at all.
  • 👥 46 other ZIP codes are made of exactly the same digits (13459, 13495, 14539, 15349, 15439, 15934, …). The farthest-flung twin is 34951 in Fort Pierce, FL, 2,487 miles away.
  • 🧭 Farther south than 58% of all ZIP codes, and farther west than 95%.
  • 🎯1,251 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 94531 and you would come out at 37.96°S, 58.22°E — 987 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 48m of daylight. Shortest: 9h 32m.
  • 📏 At 14.0 square miles of land, 94531 is bigger than 32% of ZIP codes — room for about 11 Central Parks.
🌙 The sky over 94531 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population46,387This ZIP46,387
Households13,905This ZIP13,905
Housing units14,239This ZIP14,239
Median age38.8This ZIP38.8California37.9US 38.9
Median household income$120,927This ZIP$120,927California$99,122US $80,734
Median home value$701,600This ZIP$701,600California$734,700US $332,700
Median gross rent$3,150This ZIP$3,150California$2,036US $1,413
Bachelor's degree or higher32.3%This ZIP32.3%
Mean commute44.2 minThis ZIP44.2 min
Population density3,306.7 / sq miThis ZIP3,306.7 / sq mi

Business and tax activity

Business establishments559This ZIP559
Employees7,748This ZIP7,748
Annual payroll$517,020,000This ZIP$517,020,000
Tax returns filed22,890This ZIP22,890
Total adjusted gross income$1,910,431,000This ZIP$1,910,431,000

Land area

Land area14.03 sq miThis ZIP14.03 sq mi
Water area0.00 sq mi

Other place names in 94531

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 94531

ZIPCityDistance
94509 Antioch, CA 3.1 mi
94561 Oakley, CA 5.4 mi
94513 Brentwood, CA 5.4 mi
94548 Knightsen, CA 7.0 mi
94517 Clayton, CA 7.7 mi
94565 Pittsburg, CA 8.9 mi
94511 Bethel Island, CA 9.4 mi
94527 Concord, CA 9.8 mi
94521 Concord, CA 10.5 mi
94505 Discovery Bay, CA 11.5 mi

Find every ZIP code within 10 miles of 94531 →

Questions about this ZIP code

Where is ZIP code 94531?

94531 is in Antioch, California, in Contra Costa County, part of the San Francisco-Oakland-Fremont, CA metropolitan area. Its published point location is 37.9566, -121.7778.

What county is 94531 in?

94531 lies in Contra Costa County.

What area code is 94531?

Antioch uses area code 925, from NANPA's telephone records.

What time zone is 94531 in?

94531 uses America/Los_Angeles.

How many people live in 94531?

About 46,387 people live in ZIP code 94531, in 13,905 households, at 3,306.7 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 94531?

$120,927 a year, against $99,122 across California.

What ZIP codes are near 94531?

The closest are 94509 (3.1 mi), 94561 (5.4 mi), 94513 (5.4 mi), 94548 (7 mi) and 94517 (7.7 mi).

Is 94531 a PO Box ZIP code?

94531 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “94531 ZIP Code — Antioch, California (Contra Costa County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/94531

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