Denver is served by 3 active area codes as of 2026, layered through decades of overlays and splits across the metro area. This guide walks through which code covers which part of the region, why so many codes are needed, and what new codes may come next.
The Short Answer
Denver currently has 3 active area codes in service. The count reflects a combination of population growth, the rise of mobile lines, and the way modern numbering allocates blocks — every line activated, whether a cellphone, a business desk line, a VoIP number, or a connected device, consumes a slot in the pool.
Denver has roughly 3,015,035 residents as of the most recent estimates. That population, combined with the spread of mobile and VoIP lines per household, determines how often new area codes are needed.
The Full List of Denver Area Codes
The active area codes serving Denver are listed below, in numerical order. Where a code is an overlay or a split-off from an earlier code, that relationship is noted.
- 303 — Denver-Boulder metro (Denver, Aurora, Lakewood, Boulder, Longmont, Broomfield, Castle Rock)
- 720 — Denver-Boulder metro (overlay of 303)
- 983 — Denver-Boulder metro (overlay of 303 and 720)
How Denver’s Area Codes Grew Over Time
Denver received its first area code, 303, when the North American Numbering Plan launched in 1947. That single code initially covered the entire state, and subsequent splits and overlays narrowed it over the decades that followed.
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Browse Denver Area Codes →- 1947 — 303 assigned as Colorado's sole area code at the launch of the North American Numbering Plan, covering the entire state.
- 1988 — On March 5, 1988, southeastern Colorado (Colorado Springs, Pueblo) split off from 303 as area code 719, leaving 303 to cover the Front Range and western Colorado.
- 1995 — On April 2, 1995, the northeastern and western portions of the state (Fort Collins, Grand Junction, Vail, Aspen) split off from 303 as area code 970, reducing 303 to the Denver-Boulder area.
- 1998 — On September 1, 1998, area code 720 was activated as the first overlay of 303, introducing mandatory 10-digit dialing across the Denver metro.
- 2022 — On June 17, 2022, area code 983 was activated as a second overlay of the 303/720 service area after NANPA projected the metro would otherwise exhaust available numbers by 2023.
What’s Next for Denver Area Codes
The Denver metro’s three codes form a single overlay complex. NANPA had projected the 303/720 service area would exhaust available numbers by 2023, which prompted the Colorado Public Utilities Commission to approve 983 in 2021; it went live in June 2022. With 983 still early in its assignment life, the metro has substantial runway, and no Denver numbering plan area appears on NANPA’s near-term relief schedule. The next overlay is not expected for many years.
Frequently Asked Questions
How many area codes does Denver have right now?
Denver has 3 active area codes in service across the territory it covers, including any overlays that share geography with an older code.
What is the oldest area code in Denver?
303 is the oldest active area code in Denver, assigned in 1947 when the North American Numbering Plan launched. It remains in service today, though its geographic footprint has typically been reduced by subsequent splits and overlays.
What is the newest area code in Denver?
The most recent area code addition to Denver was 983, activated in 2022. New phone lines provisioned in its service area are increasingly drawn from this code as older overlays approach exhaustion.
Why does Denver need so many area codes?
Population growth combined with the proliferation of mobile lines, business direct-dial numbers, VoIP services, and connected devices has exhausted older codes faster than the original 1947 plan anticipated. Each new area code adds roughly 7.9 million additional phone numbers to the regional pool.
How many area codes does Denver have?
The Denver metro is served by three area codes that all cover the same territory as an overlay: 303 (the original, dating to 1947), 720 (added in 1998), and 983 (added in 2022). New phone lines may be assigned any of the three depending on which has available numbers.
Is 303 or 720 the original Denver area code?
303 is the original. It was one of the first area codes assigned in 1947 and once covered all of Colorado. 720 was added in 1998 as an overlay once 303 numbers ran short, so a 720 number is just as much a Denver number as a 303 one.
Do I have to dial the area code for local calls in Denver?
Yes. Because Denver uses an overlay of 303, 720, and 983, all calls within the metro require 10-digit dialing (area code plus the seven-digit number), even when calling a neighbor.
What area code is 983?
983 is the newest Denver-area code, activated on June 17, 2022, as a second overlay alongside 303 and 720. It covers the same Denver-Boulder territory and is now a common source of new phone numbers in the metro.
Ready to Get a Number in Denver?
We carry available Denver numbers right now across multiple area codes. Order directly in 303, 720, or 983 — a one-time fee, no monthly charges, with pricing From $150 depending on the digit pattern and memorability of the number. Prefer help choosing? Call us at (212) 580-2000.
Related Reading
- Colorado Area Codes: All 6 Active Codes Explained (2026)
- The 303 Area Code Explained — Colorado Phone Numbers
- Where Is Area Code 720 Located?
- How Many Area Codes Are in the US
- How Do Area Codes Work
- How Are Area Codes Assigned
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