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zipcodes.pro — ZIP/98040

98040

ZIP 98040 is Mercer Island, Washington, in King County; Pacific time.

Type
Standard
Time zone
America/Los_Angeles
County
King
Population
25,307
Coordinates
47.5640, -122.2312
☼ Live from 98040 — Mercer Island, WA

Weather right now

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NEXRAD radar
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Local time: —

Where 98040 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 98040
  • 🔢 Type 98040 into a pocket calculator and turn it upside down: OhOBG — not quite a word, sorry.
  • ➕ As a number, 98,040 = 2 × 2 × 2 × 3 × 5 × 19 × 43. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111111011111000
  • 🏠 Its numerical neighbours: 98039 (Medina, WA, 5 mi away) and 98041 (Bothell, WA, 14 mi away).
  • 🔄 Backwards, 98040 becomes 04089, which is not a ZIP code at all.
  • 👥 23 other ZIP codes are made of exactly the same digits (00984, 04098, 08049, 08094, 08904, 09804, …). The farthest-flung twin is 09804 in APO AE, a military post office, 7,312 miles away.
  • 🧭 Farther north than 97% of all ZIP codes, and farther west than 96%.
  • 🎯1,290 miles northwest of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 98040 and you would come out at 47.56°S, 57.77°E — 583 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 59m of daylight. Shortest: 8h 26m.
  • 📏 At 6.4 square miles of land, 98040 is bigger than 21% of ZIP codes — room for about 4.8 Central Parks.
🌙 The sky over 98040 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population25,307This ZIP25,307
Households10,068This ZIP10,068
Housing units10,609This ZIP10,609
Median age46.4This ZIP46.4Washington38.3US 38.9
Median household income$219,069This ZIP$219,069Washington$98,141US $80,734
Median home value$2,000,000+This ZIP$2,000,000+Washington$564,600US $332,700
Median gross rent$2,502This ZIP$2,502Washington$1,760US $1,413
Bachelor's degree or higher81.4%This ZIP81.4%
Mean commute23.6 minThis ZIP23.6 min
Population density3,964.8 / sq miThis ZIP3,964.8 / sq mi

Business and tax activity

Business establishments830This ZIP830
Employees7,524This ZIP7,524
Annual payroll$466,919,000This ZIP$466,919,000
Tax returns filed12,700This ZIP12,700
Total adjusted gross income$5,185,558,000This ZIP$5,185,558,000

Land area

Land area6.38 sq miThis ZIP6.38 sq mi
Water area6.52 sq miThis ZIP6.52 sq mi

Other place names in 98040

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

ZIP codes near 98040

ZIPCityDistance
98118 Seattle, WA 2.3 mi
98144 Seattle, WA 3.2 mi
98009 Bellevue, WA 3.5 mi
98015 Bellevue, WA 3.5 mi
98006 Bellevue, WA 3.8 mi
98004 Bellevue, WA 3.9 mi
98108 Seattle, WA 4.0 mi
98056 Renton, WA 4.1 mi
98122 Seattle, WA 4.3 mi
98005 Bellevue, WA 4.5 mi

Find every ZIP code within 10 miles of 98040 →

Questions about this ZIP code

Where is ZIP code 98040?

98040 is in Mercer Island, Washington, in King County, part of the Seattle-Tacoma-Bellevue, WA metropolitan area. Its published point location is 47.5640, -122.2312.

What county is 98040 in?

98040 lies in King County.

What time zone is 98040 in?

98040 uses America/Los_Angeles.

How many people live in 98040?

About 25,307 people live in ZIP code 98040, in 10,068 households, at 3,964.8 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 98040?

$219,069 a year, against $98,141 across Washington.

What ZIP codes are near 98040?

The closest are 98118 (2.3 mi), 98144 (3.2 mi), 98009 (3.5 mi), 98015 (3.5 mi) and 98006 (3.8 mi).

Is 98040 a PO Box ZIP code?

98040 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “98040 ZIP Code — Mercer Island, Washington (King County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/98040

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/98040.json

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