303 Area Code
Colorado, USA
Local time now · Mountain Time
1:44 AM
Area code 303 is in Colorado, USA, serving Arvada, Highlands Ranch and Welby. It uses Mountain Time — the time there now is 1:44 AM. 720 and 983 are overlays for the same area, so local calls need 10-digit dialing. In service since 1947.
| Area code | 303 |
|---|---|
| Location | Colorado, USA |
| Major cities | Arvada, Highlands Ranch, Welby |
| Time zone | Mountain Time |
| Overlay codes | 720, 983 |
| In service since | 1947 |
| Dialing | 1+10 permissible at each service providers discretion |
Other area codes in Colorado
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Frequently asked questions
Where is area code 303?
Colorado, USA — including Arvada, Highlands Ranch and Welby.
What time zone is area code 303?
Mountain Time.
How do I call a 303 number from abroad?
Dial your international access code, then 1 (the country code), then 303 and the 7-digit number — for example +1 303 555 0100. From the UK or India dial 00 1 303 …; from Bangladesh 00 1 303 … .
Is a call from 303 a scam?
Not by itself — 303 is an ordinary geographic area code in Colorado. Numbers can be spoofed, so be careful with unexpected calls asking for money or personal details.
Sources: North American Numbering Plan Administrator (NANPA) NPA database (10/25/2026); major cities from Wikidata (CC0). An area code shows where a number was first assigned — with number portability and mobile phones, the caller may be anywhere.