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zipcodes.pro — ZIP/99403

99403

ZIP 99403 is Clarkston, Washington, mostly in Asotin County; area code 509; Pacific time.

Type
Standard
Time zone
America/Los_Angeles
County
Asotin +1 more
Metro area
Lewiston, ID-WA
Population
20,760
Coordinates
46.3755, -117.2903
☼ Live from 99403 — Clarkston, WA

Weather right now

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Local time: —

Where 99403 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 99403
  • 🔢 Type 99403 into a pocket calculator and turn it upside down: EOhGG — not quite a word, sorry.
  • ➕ As a number, 99,403 = 107 × 929. Its digits add up to 25, a total 2,242 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 11000010001001011
  • 🏠 Its numerical neighbours: 99402 (Asotin, WA, 11 mi away) and 99501 (Anchorage, AK, 1,650 mi away). Next door on paper, a road trip in real life.
  • 🔄 Backwards, 99403 becomes 30499 — and that is a real ZIP code: Reidsville, GA, 2,102 miles away.
  • 👥 19 other ZIP codes are made of exactly the same digits (04939, 30499, 34990, 39094, 40939, 43909, …). The farthest-flung twin is 34990 in Palm City, FL, 2,405 miles away.
  • 🧭 Farther north than 94% of all ZIP codes, and farther west than 90%.
  • 🎯1,043 miles northwest of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 99403 and you would come out at 46.38°S, 62.71°E — 404 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 48m of daylight. Shortest: 8h 35m.
  • 📏 At 143.5 square miles of land, 99403 is bigger than 86% of ZIP codes — room for about 109 Central Parks.
🌙 The sky over 99403 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population20,760This ZIP20,760
Households8,743This ZIP8,743
Housing units9,281This ZIP9,281
Median age45.7This ZIP45.7Washington38.3US 38.9
Median household income$71,482This ZIP$71,482Washington$98,141US $80,734
Median home value$325,300This ZIP$325,300Washington$564,600US $332,700
Median gross rent$1,036This ZIP$1,036Washington$1,760US $1,413
Bachelor's degree or higher25.0%This ZIP25.0%
Mean commute15.0 minThis ZIP15.0 min
Population density144.7 / sq miThis ZIP144.7 / sq mi

Business and tax activity

Business establishments413This ZIP413
Employees5,262This ZIP5,262
Annual payroll$259,695,000This ZIP$259,695,000
Tax returns filed9,040This ZIP9,040
Total adjusted gross income$678,843,000This ZIP$678,843,000

Land area

Land area143.49 sq miThis ZIP143.49 sq mi
Water area1.37 sq miThis ZIP1.37 sq mi

Counties 99403 spans

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

CountyShare of this ZIP
Asotin County 79.9%
Garfield County 20.1%

Other place names in 99403

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

ZIP codes near 99403

ZIPCityDistance
99402 Asotin, WA 11.1 mi
99179 Uniontown, WA 11.4 mi
99347 Pomeroy, WA 13.9 mi
99113 Colton, WA 15.1 mi
83501 Lewiston, ID 19.4 mi
99401 Anatone, WA 20.0 mi
83832 Genesee, ID 21.9 mi
83540 Lapwai, ID 24.3 mi
99163 Pullman, WA 24.8 mi
99164 Pullman, WA 25.1 mi

Find every ZIP code within 10 miles of 99403 →

Questions about this ZIP code

Where is ZIP code 99403?

99403 is in Clarkston, Washington, in Asotin County, part of the Lewiston, ID-WA metropolitan area. Its published point location is 46.3755, -117.2903.

What county is 99403 in?

99403 spans 2 counties: Asotin County and Garfield County. Most of it falls in Asotin 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 99403?

Clarkston uses area code 509, from NANPA's telephone records.

What time zone is 99403 in?

99403 uses America/Los_Angeles.

How many people live in 99403?

About 20,760 people live in ZIP code 99403, in 8,743 households, at 144.7 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 99403?

$71,482 a year, against $98,141 across Washington.

What ZIP codes are near 99403?

The closest are 99402 (11.1 mi), 99179 (11.4 mi), 99347 (13.9 mi), 99113 (15.1 mi) and 83501 (19.4 mi).

Is 99403 a PO Box ZIP code?

99403 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “99403 ZIP Code — Clarkston, Washington (Asotin County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/99403

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/99403.json

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