Colorado · Mountain Time
Fort Collins, CO Area Codes
Fort Collins is served by 2 area codes (748, 970). Here's which is original, which are overlays, and how to pick one for a new local number.
Last updated June 5, 2026
Area codes serving Fort Collins
Fort Collins sits in Colorado, part of the West region and the Mountain Time zone. Its numbers are spread across an overlay of 2 codes that all cover the same ground: 748, 970.
The original code is 748. As the area ran low on numbers, regulators added overlay codes on top instead of splitting the city, so longtime residents kept their numbers while new lines received a newer code.
How to pick an area code for a new number
When you activate a new line in Fort Collins, the carrier assigns whichever code has numbers available — you usually can't choose. If a specific code matters to you (for example the prestige of 748), ask the carrier whether any blocks remain, or request a number transfer. All codes here dial identically and cost the same.
Dialing in Fort Collins
Because Fort Collins is an overlay area, 10-digit dialing is mandatory: always dial the area code plus the seven-digit number, even for a neighbor. See 10-digit dialing and overlay area codes for the background. For every code in Colorado, visit the Colorado area codes page.
Quick answers
Fort Collins area code FAQ
What area codes does Fort Collins use?
Fort Collins, CO is served by 2 area codes: 748, 970.
Which is the original Fort Collins area code?
748 is the original/primary code for Fort Collins; the others are overlays added later for more numbers.
Do I need to dial the area code in Fort Collins?
Yes. With multiple overlapping codes, 10-digit dialing is required for every call in this area.