Get a local business phone number in Denver, CO

What area code is Denver, CO?

With 729,019 residents in the Census 2024 estimate, Denver sits in Denver County, Colorado. NANPA lists 1,445 exchanges for its rate center across 3 area codes; 303 has the most (735, 51%). 303 is part of an overlay with 720 and 983, so a new local number in Denver may carry any of those codes depending on which have numbers available. Denver is in the Mountain time zone.

According to NANPA's dialing-plan data, local calls within 303 are dialed as ten digits (area code plus number) and toll calls as 1 plus ten digits.

Denver exchanges by carrier

62 carriers hold the 1,445 exchanges assigned to Denver's rate center. Qwest Corporation has the most, with 527. 775 of them are pooled codes, which the holder shares with other carriers in blocks of 1,000 numbers. Holding a code means NANPA assigned that block of numbers to the carrier for this rate center; individual numbers may since have been ported elsewhere.

Denver phone prefixes

Each prefix below is a block of up to 10,000 numbers that NANPA assigned to Denver's rate center (DENVER). The earliest assignment date recorded in the file for these codes is 2001. 94 of the 1,445 were assigned in 2020 or later.

When Denver's exchanges were assigned

Assignment dates show when each block of Denver numbers was added to the local supply.

What makes a number local to Denver

What a caller sees as "local" is the area code plus prefix. In Denver, those come from the DENVER rate center, as recorded by NANPA.

New local numbers are drawn from carrier inventory, so the exact 303 numbers available change over time; porting an existing number is free.

Businesses around Denver

Denver is part of the Denver-Aurora-Centennial, CO metro area, home to 3.1 million people in 2024. County Business Patterns counted 91,522 business establishments in the Denver, CO metro area in 2023, employing 1,419,833 people. The largest sectors by establishment count are professional, scientific, and technical services (15,561), health care and social assistance (10,010), and construction (9,143).

Business phone service in Denver

Callata Office costs $99 per month for up to 5 people, and each additional user is $20 a month. That covers up to 3 local numbers, calling from a browser or your cell, transcribed voicemail, recorded calls with AI summaries, after-hours routing and E911 on each number.

If you already have a number in Denver, porting it to Callata is free. Texting from a local number requires a one-time carrier registration (10DLC, $49), and the numbers available in any area code depend on carrier inventory when you choose them.

Optional AI agents (receptionist, sales, support or scheduler) can answer calls after hours or when nobody picks up, take messages, text, email and transfer to your team. They are billed from prepaid AI minutes at $0.25 per minute, identify themselves as AI, and may only place outbound calls to people who consented, between 8am and 9pm.

Per-seat phone plans multiply by headcount. For the rounded average establishment size in the Denver, CO metro area, 16 users on RingCentral RingEX Core come to $480.00 a month and on Ooma Office Pro $399.20, at month-to-month list prices checked September 28, 2026. On Callata the same 16 people cost $319.00 a month, less than either per-seat plan.