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zipcodes.pro — ZIP/81638

81638

ZIP 81638 is Hamilton, Colorado, mostly in Moffat County; area code 970; Mountain time.

Type
Standard
Time zone
America/Denver
County
Moffat +1 more
Population
69
Coordinates
40.3004, -107.6427
☼ Live from 81638 — Hamilton, CO

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Where 81638 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 81638
  • 🔢 Type 81638 into a pocket calculator and turn it upside down: BEgIB — not quite a word, sorry.
  • ➕ As a number, 81,638 = 2 × 40819. Its digits add up to 26, a total 2,038 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 10011111011100110
  • 🏠 Its numerical neighbours: 81637 (Gypsum, CO, 46 mi away) and 81639 (Hayden, CO, 28 mi away).
  • 🔄 Backwards, 81638 becomes 83618, which is not a ZIP code at all.
  • 👥 18 other ZIP codes are made of exactly the same digits (16388, 16838, 38168, 38186, 38618, 61883, …). The farthest-flung twin is 16838 in Grampian, PA, 1,513 miles away.
  • 🧭 Farther north than 59% of all ZIP codes, and farther west than 85%.
  • 🎯480 miles west of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 81638 and you would come out at 40.30°S, 72.36°E — 634 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 03m of daylight. Shortest: 9h 18m.
  • 📏 At 418.1 square miles of land, 81638 is bigger than 97% of ZIP codes — room for about 317 Central Parks.
🌙 The sky over 81638 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population69This ZIP69
Households41This ZIP41
Housing units113This ZIP113
Median age72.7This ZIP72.7Colorado37.7US 38.9
Bachelor's degree or higher49.3%This ZIP49.3%
Population density0.2 / sq miThis ZIP0.2 / sq mi

Business and tax activity

Business establishments5This ZIP5
Employees3This ZIP3
Annual payroll$173,000This ZIP$173,000

Land area

Land area418.12 sq miThis ZIP418.12 sq mi
Water area0.12 sq miThis ZIP0.12 sq mi

Counties 81638 spans

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

CountyShare of this ZIP
Moffat County 77.2%
Routt County 22.8%

ZIP codes near 81638

ZIPCityDistance
81626 Craig, CO 15.7 mi
81641 Meeker, CO 16.1 mi
81639 Hayden, CO 27.7 mi
81625 Craig, CO 28.4 mi
80469 Phippsburg, CO 36.1 mi
80483 Yampa, CO 40.0 mi
80467 Oak Creek, CO 43.5 mi
81633 Dinosaur, CO 43.9 mi
80487 Steamboat Springs, CO 44.3 mi
80477 Steamboat Springs, CO 44.5 mi

Find every ZIP code within 10 miles of 81638 →

Questions about this ZIP code

Where is ZIP code 81638?

81638 is in Hamilton, Colorado, in Moffat County, part of the Steamboat Springs, CO micropolitan area. Its published point location is 40.3004, -107.6427.

What county is 81638 in?

81638 spans 2 counties: Moffat County and Routt County. Most of it falls in Moffat 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 81638?

Hamilton uses area code 970, from NANPA's telephone records.

What time zone is 81638 in?

81638 uses America/Denver.

How many people live in 81638?

About 69 people live in ZIP code 81638, in 41 households, at 0.2 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What ZIP codes are near 81638?

The closest are 81626 (15.7 mi), 81641 (16.1 mi), 81639 (27.7 mi), 81625 (28.4 mi) and 80469 (36.1 mi).

Is 81638 a PO Box ZIP code?

81638 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “81638 ZIP Code — Hamilton, Colorado (Moffat County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/81638

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