ZIP code · Hamilton · Colorado · United States
ZIP code 81638 — Hamilton
ZIP code 81638 serves Hamilton, Colorado.
- Postal code
- 81638Single source Value from one source, not cross-checked.
- City
- Hamilton
- County
- Moffat FIPS 08081
- State
- Colorado
- Country
- United States
- Coordinates
- 40.3250, -107.5841 — precision precise (locality)
View on OpenStreetMap - Population
- 94 (ZCTA, ACS 5-year)
- Population density
- 0 / sq mi
- Land area
- 418.1 sq mi (1,082.9 km²) (ZCTA, ACS 5-year)
- Per-capita income
- $35,597
- Median age
- 65.8
- Households
- 44
- Housing units
- 90
- Congressional districts
- CO-3 (also CO-2) (119th Congress)
- USDA hardiness zone
- 5b (-15 to -10 °F)Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
- Time zone
- America/Denver (UTC−7 / UTC−6 DST)
- Area code
- 970 (from the nearest rate centre)Telephone area codes serving this ZIP (NANPA central-office assignments). A ZIP and an area code are different boundaries; at a border both codes may apply.
Tools: compare 81638 with another ZIP · ZIPs within 25 miles · distance from 81638
Map of ZIP code 81638
Climate — monthly normals
Warmest month Jul (avg high 85°F), coldest Jan (avg low 7°F).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 30 | 35 | 47 | 56 | 66 | 78 | 85 | 83 | 75 | 61 | 45 | 32 |
| Avg low °F | 7 | 11 | 20 | 27 | 36 | 43 | 50 | 48 | 39 | 28 | 18 | 9 |
| Precip in | 1.2 | 1.1 | 1.3 | 1.9 | 1.9 | 1.1 | 1.2 | 1.3 | 1.8 | 1.8 | 1.4 | 1.4 |
NOAA 1991–2020 climate normals from the nearest station: CRAIG 4SW (8.8 mi) · NOAA NCEI
Places in ZIP 81638
- 1 schools
Places mapped inside this ZIP’s ZCTA area in OpenStreetMap. OSM is community-maintained: counts reflect what has been mapped, and completeness varies by area — treat them as at-least figures. © OpenStreetMap contributors (ODbL) · Methodology
About this page
US ZIP codes have five digits. They are postal routing areas, not administrative boundaries: a ZIP can span more than one city or county, and the city shown is the primary USPS name for that code.
GeoNames · U.S. Census Bureau (ACS) · U.S. Census Bureau · NOAA NCEI · usda-phzm. Data generated on 2026-08-21. Methodology · Report an error on this page