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zipcodes.pro — ZIP/94028

94028

ZIP 94028 is Portola Valley, California, mostly in San Mateo County; area code 650; Pacific time.

Type
Standard
Time zone
America/Los_Angeles
County
San Mateo +1 more
Population
6,531
Coordinates
37.3749, -122.2127
☼ Live from 94028 — Portola Valley, CA

Weather right now

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Local time: —

Where 94028 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 94028
  • 🔢 Type 94028 into a pocket calculator and turn it upside down: BZOhG — not quite a word, sorry.
  • ➕ As a number, 94,028 = 2 × 2 × 11 × 2137. Its digits add up to 23, a total 2,533 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10110111101001100
  • 🏠 Its numerical neighbours: 94027 (Atherton, CA, 6 mi away) and 94030 (Millbrae, CA, 19 mi away).
  • 🔄 Backwards, 94028 becomes 82049, which is not a ZIP code at all.
  • 👥 51 other ZIP codes are made of exactly the same digits (02894, 04289, 04928, 04982, 09248, 09824, …). The farthest-flung twin is 09824 in APO AE, a military post office, 7,101 miles away.
  • 🧭 Farther south than 62% of all ZIP codes, and farther west than 96%.
  • 🎯1,284 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 94028 and you would come out at 37.37°S, 57.79°E — 1,034 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 44m of daylight. Shortest: 9h 35m.
  • 📏 At 17.3 square miles of land, 94028 is bigger than 35% of ZIP codes — room for about 13 Central Parks.
🌙 The sky over 94028 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population6,531This ZIP6,531
Households2,637This ZIP2,637
Housing units2,808This ZIP2,808
Median age57.2This ZIP57.2California37.9US 38.9
Median household income$250,000+This ZIP$250,000+California$99,122US $80,734
Median home value$2,000,000+This ZIP$2,000,000+California$734,700US $332,700
Median gross rent$3,500+This ZIP$3,500+California$2,036US $1,413
Bachelor's degree or higher82.9%This ZIP82.9%
Mean commute17.7 minThis ZIP17.7 min
Population density377.1 / sq miThis ZIP377.1 / sq mi

Business and tax activity

Business establishments210This ZIP210
Employees1,822This ZIP1,822
Annual payroll$140,292,000This ZIP$140,292,000
Tax returns filed3,360This ZIP3,360
Total adjusted gross income$3,295,277,000This ZIP$3,295,277,000

Land area

Land area17.32 sq miThis ZIP17.32 sq mi
Water area0.09 sq miThis ZIP0.09 sq mi

Counties 94028 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
San Mateo County 81.1%
Santa Clara County 18.9%

Other place names in 94028

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

ZIP codes near 94028

ZIPCityDistance
94304 Palo Alto, CA 2.9 mi
94305 Stanford, CA 3.8 mi
94022 Los Altos, CA 4.0 mi
94062 Redwood City, CA 5.2 mi
94306 Palo Alto, CA 5.3 mi
94023 Los Altos, CA 5.5 mi
94025 Menlo Park, CA 5.5 mi
94027 Atherton, CA 5.7 mi
94301 Palo Alto, CA 5.9 mi
94302 Palo Alto, CA 6.0 mi

Find every ZIP code within 10 miles of 94028 →

Questions about this ZIP code

Where is ZIP code 94028?

94028 is in Portola Valley, California, in San Mateo County, part of the San Francisco-Oakland-Fremont, CA metropolitan area. Its published point location is 37.3749, -122.2127.

What county is 94028 in?

94028 spans 2 counties: San Mateo County and Santa Clara County. Most of it falls in San Mateo County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 94028?

Portola Valley uses area code 650, from NANPA's telephone records.

What time zone is 94028 in?

94028 uses America/Los_Angeles.

How many people live in 94028?

About 6,531 people live in ZIP code 94028, in 2,637 households, at 377.1 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 94028?

$250,000+ a year, against $99,122 across California.

What ZIP codes are near 94028?

The closest are 94304 (2.9 mi), 94305 (3.8 mi), 94022 (4 mi), 94062 (5.2 mi) and 94306 (5.3 mi).

Is 94028 a PO Box ZIP code?

94028 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “94028 ZIP Code — Portola Valley, California (San Mateo County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/94028

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