NANP area code
970
UTC−7, UTC−6 during daylight saving
- State
- Colorado
- Primary city
- Fort Collins
- Time zone
- Mountain
- In service
- 1995
- Overlay
- 748
NANP area code
970
UTC−7, UTC−6 during daylight saving
The code reaches 199 communities and 32 counties across Colorado.
The area code itself carries no risk signal. 970 is assigned to Fort Collins, Colorado, so a call from it is consistent with a real caller in that area — but the digits alone prove nothing, because they can be forged.
Caller ID is set by whoever places the call, not verified by the network. That is why neighbour spoofing works: an operation anywhere in the world can display a number that matches the area code — and often the first three digits after it — of the person being called, so the call looks local. Every community in the 970 territory is a plausible-looking origin for a forged 970 number, which is why one can be made to look like a neighbour to so many people. The same applies to its overlay code 748, which serves the same ground.
If you did not recognise the call: let it go to voicemail — a legitimate caller with real business will leave one. Do not return the call using the number shown; look the organisation up independently and call the number you found. Never confirm personal details, card numbers, or one-time codes to someone who called you, however plausible the number looked.
Codes.zone publishes no complaint counts, risk scores, or caller identities. We hold no data on individual numbers and will not estimate what we cannot source.
Time there now
—
Mountain · UTC−7, UTC−6 during daylight saving
Reasonable callback window
8:00 AM – 9:00 PM
local time in Mountain
Federal rules bar telemarketing calls to a residence outside 8:00 AM–9:00 PM in the called party's own time zone. It is a sensible bound for a personal callback too — and a caller who rang you well outside it was not observing it.
970 does not have its territory to itself. 748 covers the same ground, serving Fort Collins and the rest of the 970 territory. An overlay is what a regulator adds when a region runs out of assignable numbers: rather than splitting the area and forcing half the residents to change their number, a second code is laid over the top and new numbers are issued from it.
The practical consequence: two neighbours on the same street can hold numbers in different area codes, so the code tells you nothing about which part of town a caller is in — and local calls must be dialled as all ten digits, because seven is no longer unambiguous.
| City | ZIP codes | County |
|---|---|---|
| Fort Collins | 9 | Larimer County |
| Grand Junction | 7 | Mesa County |
| Greeley | 6 | Weld County |
| Durango | 3 | La Plata County |
| Loveland | 3 | Larimer County |
| Montrose | 3 | Montrose County |
| Steamboat Springs | 3 | Routt County |
| Aspen | 2 | Pitkin County |
| Craig | 2 | Moffat County |
| Crested Butte | 2 | Gunnison County |
| Dinosaur | 2 | Moffat County |
| Estes Park | 2 | Larimer County |
| Glenwood Springs | 2 | Garfield County |
| Gunnison | 2 | Gunnison County |
| Pagosa Springs | 2 | Archuleta County |
| Silverthorne | 2 | Summit County |
| Vail | 2 | Eagle County |
| Windsor | 2 | Weld County |
| Akron | 1 | Washington County |
| Almont | 1 | Gunnison County |
179 further communities not listed. All Colorado area codes →
Scope every community matched to 970. Source geoinfo-dataset (full_dataset) ZIP→NPA (2018 snapshot), GeoNames US postal codes (2026-07 postal dump) and Census 2024 county Gazetteer (2024 Gazetteer). Updated . Coordinates are place reference points, not boundaries.
We do not publish the NXX prefixes inside 970. The assignment of prefixes to rate centres comes from LERG routing data, which is proprietary, and we will not estimate it from postal data — ZIP codes and telephone prefixes do not map onto each other. Awaiting a clean-rights NPA-NXX source.
970 has served this territory since 1995. It eventually ran short of exchanges to hand out, and rather than split the region and make half its residents change their number, the regulator laid 748 over the same ground in 2025. New lines here are issued from the newer code, which is why a neighbour’s number may not start with 970.