303 area code
The 303 area code covers Denver, Boulder and the suburbs around them, Colorado. Main cities include Denver, Aurora, Boulder, Lakewood, Littleton and Broomfield.
- State
- Colorado
- Main cities
- Denver, Aurora, Boulder, Lakewood, Littleton, Broomfield
- Time zone
- Mountain Time
- Same area as
- 720, 983
- In service since
- 1947
- Local calls
- 10 digits
Get a free 303 number for your business
Pick 303 when you set up your number and Scheduley gives your business a local Denver number for calls and texts, answered 24/7 by an AI receptionist that books appointments and jobs. The number is free. AI calls are $2 a minute after your 10 welcome minutes.
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Where is the 303 area code?
Area code 303 covers Denver, Boulder and the suburbs around them, Colorado, including Denver, Aurora, Boulder, Lakewood, Littleton and Broomfield. It went into service in 1947, as one of the original North American area codes. It shares the same area with 720 and 983, so new local numbers there can get any of these codes. Local calls need all 10 digits.
Got a call from a 303 number?
A 303 number was first given out in the Denver area. Area codes show where a number was assigned, not where the caller is today, and spam callers can fake any number. If you don’t know the caller, let it go to voicemail or look up the full number before you call back.
303 area code FAQ
Where is the 303 area code?
303 covers Denver, Boulder and the suburbs around them, Colorado, including Denver, Aurora, Boulder, Lakewood, Littleton and Broomfield.
What time zone is area code 303?
Area code 303 is on Mountain Time.
What other area codes cover the same area as 303?
720 and 983. They’re overlay codes for the same area, so a local number there can have any of them.
Can I get a free 303 business phone number?
Yes. Pick 303 when you set up your Scheduley number and it gets a local number for you, if one is available. The number is free, and an AI receptionist can answer it 24/7 and book appointments.