Boulder, CO Metro Area
The Boulder, CO metro area is one county in Colorado: Boulder County. About 328,560 people lived there on July 1, 2025 (Census estimate), 0.7% fewer than in April 2020.
- Population, July 2025
- 328,560 0.7% fewer than in April 2020
- Type
- Metropolitan statistical area
- County
- Boulder County
- Land area
- 726 sq mi (1,881 km²)
- Time zone
- Mountain TimeUTC-07:00 in January; UTC-06:00 in July
- State
- Colorado
- Combined statistical area
- Denver-Aurora-Greeley, CO
- CBSA code
- 14500
The county in the Boulder, CO metro area
| County | Role | Population, July 2025 |
|---|---|---|
| Boulder County | Central | 328,560 |
A central county holds the area’s core, an urban area of at least 50,000 people. This area has no outlying counties: no neighboring county sends enough commuters to join it. A county belongs to one metro or micro area at most, and it counts whole, countryside included.
Principal city
- Boulder106,433 people
OMB names the area after its largest principal cities. A principal city is the area’s largest city, plus any other city that is very large or a big job center, and smaller ones with at least as many jobs as working residents (2020 Census and commuting figures). People counts are American Community Survey 2020–2024 5-year estimates.
Part of the Denver-Aurora-Greeley, CO combined statistical area
OMB joins neighboring metro and micro areas into a combined statistical area when enough people commute between them. The other 2 areas in this one, largest first:
- Denver-Aurora-Centennial, CO Metro Area3,092,037 people
- Greeley, CO Metro Area378,426 people
Bordering metro and micro areas, nearest first
Areas with a county on this area’s edge. Distances are straight lines between the areas’ largest cities.
- Denver-Aurora-Centennial, CO Metro Area27 mi southeast
- Greeley, CO Metro Area37 mi northeast
- Fort Collins-Loveland, CO Metro Area38 mi north
Before using this answer on a form
A metro or micro area is a statistical area that OMB draws for federal statistics. It is not a city, a local government or a mailing address, and it is not a measure of urban and rural: whole counties count, rural parts included. Programs that use metro areas, such as housing income limits or wage rates, can use their own version of these lists; check the program’s own list for an address.
Find the metro area where you are now, find your county, or see every metro and micro area by population.