Area codes in Denver, Colorado
Denver, Colorado uses 3 area codes — 303, 720 and 983. The main Denver area code is 303.
Area codes serving Denver
Phone numbers in Denver are written as ten digits — for example (303) 555-0190 — and fall in the Mountain Time zone.
How Denver came to have 3 area codes
The original Denver area code is 303, in service since 1947. As the area ran low on available numbers, overlay codes were added over the same region for new phone lines: 720 (1998) and 983 (2022). Existing numbers kept their original code — an overlay never forces anyone to change their number — which is why Denver now uses all 3 codes and every local call is dialed with ten digits.
All Colorado area codes · Is a Denver call a scam?
Nearby cities
- Westminster area codes
- Lakewood area codes
- Aurora area codes
- Brighton area codes
- Littleton area codes
- Boulder area codes
- Longmont area codes
- Loveland area codes
More cities in Colorado
Frequently asked questions
What is the area code for Denver?
The main area code for Denver, Colorado is 303. Denver is now served by 3 area codes in total: 303, 720, 983.
How many area codes does Denver have?
Denver has 3 area codes: 303, 720, 983.
Why does Denver have more than one area code?
As Denver used up the numbers available in its original area code (303, in service since 1947), additional "overlay" codes were added over the same area so new phone numbers could keep being assigned.
How do you dial a Denver number?
Dial all 10 digits — the area code (303 or 720 or 983) followed by the 7-digit local number. From abroad, dial +1, then the area code and number.
Sourced from the official NANPA (North American Numbering Plan Administrator) numbering database, current as of August 2, 2026. Refreshed monthly.