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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/98121

98121

ZIP 98121 is in Seattle, Washington, in King County; area code 206; Pacific time. Seattle has 59 ZIP codes in all.

Type
Standard
Time zone
America/Los_Angeles
County
King
Population
21,166
Coordinates
47.6152, -122.3506
☼ Live from 98121 — Seattle, WA

Weather right now

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Local time: —

Where 98121 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 98121
  • 🔢 Type 98121 into a pocket calculator and turn it upside down: IZIBG — not quite a word, sorry.
  • ➕ As a number, 98,121 = 3 × 32707. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10111111101001001
  • 🏠 Its numerical neighbours: 98119 (Seattle, WA, 2 mi away) and 98122 (Seattle, WA, 3 mi away).
  • 🔄 Backwards, 98121 becomes 12189 — and that is a real ZIP code: Watervliet, NY, 2,353 miles away.
  • 👥 20 other ZIP codes are made of exactly the same digits (12189, 12198, 12819, 12918, 12981, 18219, …). The farthest-flung twin is 19182 in Philadelphia, PA, 2,375 miles away.
  • 🧭 Farther north than 97% of all ZIP codes, and farther west than 96%.
  • 🎯1,296 miles northwest of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 98121 and you would come out at 47.62°S, 57.65°E — 587 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 25m.
  • 📏 At 0.444 square miles of land, 98121 is bigger than 5% of ZIP codes — about 215 football fields.
🌙 The sky over 98121 today
  • Working out the sun…
🌋 Shake report
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Source: USGS.

People and housing

Population21,166This ZIP21,166
Households14,288This ZIP14,288
Housing units16,684This ZIP16,684
Median age33.2This ZIP33.2Washington38.3US 38.9
Median household income$152,019This ZIP$152,019Washington$98,141US $80,734
Median home value$848,400This ZIP$848,400Washington$564,600US $332,700
Median gross rent$2,337This ZIP$2,337Washington$1,760US $1,413
Bachelor's degree or higher78.9%This ZIP78.9%
Mean commute20.3 minThis ZIP20.3 min
Population density47,671.2 / sq miThis ZIP47,671.2 / sq mi

Business and tax activity

Business establishments1,199This ZIP1,199
Employees34,570This ZIP34,570
Annual payroll$4,089,018,000This ZIP$4,089,018,000
Tax returns filed13,310This ZIP13,310
Total adjusted gross income$2,573,135,000This ZIP$2,573,135,000

Land area

Land area0.44 sq miThis ZIP0.44 sq mi
Water area0.20 sq miThis ZIP0.20 sq mi

Other place names in 98121

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

ZIP codes near 98121

ZIPCityDistance
98141 Seattle, WA 0.3 mi
98101 Seattle, WA 0.7 mi
98170 Seattle, WA 1.0 mi
98154 Seattle, WA 1.0 mi
98174 Seattle, WA 1.0 mi
98111 Seattle, WA 1.1 mi
98114 Seattle, WA 1.1 mi
98124 Seattle, WA 1.1 mi
98129 Seattle, WA 1.1 mi
98131 Seattle, WA 1.1 mi

Find every ZIP code within 10 miles of 98121 →

Questions about this ZIP code

Where is ZIP code 98121?

98121 is in Seattle, Washington, in King County, part of the Seattle-Tacoma-Bellevue, WA metropolitan area. Its published point location is 47.6152, -122.3506.

What county is 98121 in?

98121 lies in King County.

What area code is 98121?

Seattle uses area code 206, from NANPA's telephone records.

What time zone is 98121 in?

98121 uses America/Los_Angeles.

How many people live in 98121?

About 21,166 people live in ZIP code 98121, in 14,288 households, at 47,671.2 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 98121?

$152,019 a year, against $98,141 across Washington.

What ZIP codes are near 98121?

The closest are 98141 (0.3 mi), 98101 (0.7 mi), 98170 (1 mi), 98154 (1 mi) and 98174 (1 mi).

Is 98121 a PO Box ZIP code?

98121 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “98121 ZIP Code — Seattle, Washington (King County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/98121

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