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ZIP Code Database - Facts & Stats

Data Last Updated: September 1, 2021

ZIP Codes for City of Niwot, CO

Niwot, CO Covers 3 ZIP Codes

ZIP CodeTypeCountyPopulationArea Code(s)
ZIP Code 80503StandardBoulder31,064720 / 303
ZIP Code 80504StandardWeld46,876720 / 303
ZIP Code 80544P.O. BoxBoulder111303

Timezone(s):Mountain (GMT -07:00)
Counties:BOULDER, CO
Population:4,006 (More Details)
Male Population:1,949
Female Population:2,057
Median Age:47
ZIP Codes:3
Area Codes:2
Total Area:4,017 square miles (county)
Land Area:3,987 square miles (county)
Water Area:30 square miles (county)

Niwot, CO Demographic Information *

Total population4,006
Male population1,949
Female population2,057
Median age (years)46.7
White Population3,763
Black Population22
Indian Population9
Asian Population97
Hawaiian Population2
Hispanic Population131
Median age (Male)47
Median age (Female)46.5
Total households1,582
Family households (families)1,125
Average household size2.53
Average family size3.03
Total housing units1,669
* Demographic data is based on 2010 Census.

Niwot, CO Other Information

64 Cities within 30 miles of Niwot, CO Products


  1. U.S. Postal Service [Last Updated: 9/1/2021],
  2. Internal Data Creation [Last Updated: 9/1/2021],
  3. U.S. Geological Survey [Updated as needed],
  4. U.S. Census [Updated Yearly],
  5. U.S. Census 2010 [Decennial] [Last Updated: 1/1/2010],