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303 area code: who called me?
- Area code
- 303
- Serves
- Denver, CO
- State
- Colorado
- Time zone
- Mountain
- International format
- +1 303 …
303 is the area code for Denver, Colorado. 720 shares its territory as an overlay.
Denver
303 was originally Colorado's only code. Today it serves Denver and its western and northern suburbs, with 720 as an overlay, which requires ten-digit dialing. The area is on Mountain time.
Denver has grown quickly, so many people who hold a 303 number came from elsewhere and kept their number. Always check the full number.
Besides Denver, the code covers Boulder, Aurora and other Front Range cities along the foot of the Rocky Mountains. Colorado's cannabis, tech and outdoor industries all place calls from these numbers.
Hail season and storm chasers
Colorado's Front Range gets frequent hailstorms, and afterward door-to-door and phone callers offer to repair roofs. Check the contractor's license and references, get a written estimate and do not sign over your insurance payment.
Callers who claim to be from the power company are also reported. Xcel Energy and other utilities say they do not demand payment by gift card.
Does the area code show where the caller is?
Not reliably. Scammers and call centers use spoofing to display a local area code because people are more likely to answer. People also keep their number when they move, so a 303 number can belong to someone anywhere.
That is why the full number matters more than the code. If someone has already reported it, you will see it below.
Reported 303 numbers
Nobody has reported a number from this area code yet.