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ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/94401

94401

ZIP 94401 is in San Mateo, California, in San Mateo County; area code 650; Pacific time. San Mateo has 5 ZIP codes; the others are 94402, 94403, 94404 and 94497.

Type
Standard
Time zone
America/Los_Angeles
County
San Mateo
Population
35,295
Coordinates
37.5752, -122.3199
☼ Live from 94401 — San Mateo, CA

Weather right now

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Local time: —

Where 94401 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 94401
  • 🔢 Type 94401 into a pocket calculator and turn it upside down: IOhhG — not quite a word, sorry.
  • ➕ As a number, 94,401 = 3 × 3 × 17 × 617. Its digits add up to 18, a total 2,332 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111000011000001
  • 🏠 Its numerical neighbours: 94309 (Palo Alto, CA, 13 mi away) and 94402 (San Mateo, CA, 2 mi away).
  • 🔄 Backwards, 94401 becomes 10449, which is not a ZIP code at all.
  • 👥 28 other ZIP codes are made of exactly the same digits (01944, 04419, 04491, 04941, 09144, 14094, …). The farthest-flung twin is 09144 in APO AE, a military post office, 5,676 miles away.
  • 🧭 Farther south than 61% of all ZIP codes, and farther west than 96%.
  • 🎯1,286 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 94401 and you would come out at 37.58°S, 57.68°E — 1,025 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 46m of daylight. Shortest: 9h 34m.
  • 📏 At 3.1 square miles of land, 94401 is bigger than 15% of ZIP codes — room for about 2.4 Central Parks.
🌙 The sky over 94401 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population35,295This ZIP35,295
Households13,026This ZIP13,026
Housing units13,818This ZIP13,818
Median age35.9This ZIP35.9California37.9US 38.9
Median household income$122,227This ZIP$122,227California$99,122US $80,734
Median home value$1,184,500This ZIP$1,184,500California$734,700US $332,700
Median gross rent$2,762This ZIP$2,762California$2,036US $1,413
Bachelor's degree or higher46.3%This ZIP46.3%
Mean commute25.7 minThis ZIP25.7 min
Population density11,345.2 / sq miThis ZIP11,345.2 / sq mi

Business and tax activity

Business establishments1,162This ZIP1,162
Employees15,587This ZIP15,587
Annual payroll$1,548,069,000This ZIP$1,548,069,000
Tax returns filed16,720This ZIP16,720
Total adjusted gross income$2,174,217,000This ZIP$2,174,217,000

Land area

Land area3.11 sq miThis ZIP3.11 sq mi
Water area0.00 sq miThis ZIP0.00 sq mi

Other place names in 94401

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

ZIP codes near 94401

ZIPCityDistance
94402 San Mateo, CA 2.5 mi
94011 Burlingame, CA 2.6 mi
94403 San Mateo, CA 2.7 mi
94497 San Mateo, CA 2.8 mi
94010 Burlingame, CA 3.0 mi
94404 San Mateo, CA 3.2 mi
94002 Belmont, CA 4.4 mi
94128 San Francisco, CA 4.8 mi
94065 Redwood City, CA 4.8 mi
94030 Millbrae, CA 4.9 mi

Find every ZIP code within 10 miles of 94401 →

Questions about this ZIP code

Where is ZIP code 94401?

94401 is in San Mateo, California, in San Mateo County, part of the San Francisco-Oakland-Fremont, CA metropolitan area. Its published point location is 37.5752, -122.3199.

What county is 94401 in?

94401 lies in San Mateo County.

What area code is 94401?

San Mateo uses area code 650, from NANPA's telephone records.

What time zone is 94401 in?

94401 uses America/Los_Angeles.

How many people live in 94401?

About 35,295 people live in ZIP code 94401, in 13,026 households, at 11,345.2 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 94401?

$122,227 a year, against $99,122 across California.

What ZIP codes are near 94401?

The closest are 94402 (2.5 mi), 94011 (2.6 mi), 94403 (2.7 mi), 94497 (2.8 mi) and 94010 (3 mi).

Is 94401 a PO Box ZIP code?

94401 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “94401 ZIP Code — San Mateo, California (San Mateo County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/94401

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