Area Code Overview

Area code 720 is a geographic telephone area code in Colorado that went into service on June 1, 1998. The geographic regions covered by this area code overlay has a population of approximately 967,697.

Overlay and Dialing Rules

Area Code: 720
State: Colorado
Type: General Purpose Code
In Service Date: June 1, 1998
Overlay Complex: 303/720/983
Local Dialing Plan: This area does require you to dial the area code when calling locally.

Estimated Number of Assigned Phone Numbers in Area Code 720

This area code is ranked 13th out of 363 nationwide in estimated assigned phone numbers. Within the state territory it serves, it is ranked 1st out of 5.

7,071,000

Estimated Service-Type Mix of Assigned Phone Numbers in Area Code 720

Total assigned 7,071,000

Wireless

3,306,000 assigned

46.75%

Wireline and VoIP

3,522,000 assigned

49.81%

Other / Unclassified

243,000 assigned

3.44%

Estimated Share of Wireless Numbers Originally Assigned to Each Carrier in Area Code 720

Estimated assigned wireless phone numbers: 3,306,000

Numbers may later be ported to another carrier, but this chart reflects original number assignment, not current subscriber share.

T-Mobile 1,307,000 (39.53%)

Verizon Wireless 1,035,000 (31.31%)

AT&T Wireless 961,000 (29.07%)

COMMNET WIRELESS, LLC 2,000 (0.06%)

Optimum Mobile 1,000 (0.03%)

Estimated Share of Wireline and VoIP Numbers Originally Assigned to Each Carrier in Area Code 720

Estimated assigned wireline and VoIP phone numbers: 3,522,000

Lumen 1,129,000 (32.06%)

Onvoy 808,000 (22.94%)

Bandwidth 621,000 (17.63%)

MCIMETRO ACCESS TRANSMISSION SERVICES LLC 260,000 (7.38%)

Comcast Business 252,000 (7.16%)

Peerless Network 121,000 (3.44%)

PAETEC ITEL, LLC 70,000 (1.99%)

Spectrum 59,000 (1.68%)

ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 56,000 (1.59%)

Telnyx 39,000 (1.11%)

AT&T 36,000 (1.02%)

Commio 17,000 (0.48%)

Other / Unclassified Assigned Numbering in Area Code 720

Estimated assigned other or unclassified phone numbers: 243,000

TELEPORT COMMUNICATIONS AMERICA, LLC - CO 140,000 (57.61%)

HD CARRIER LLC 30,000 (12.35%)

INTRADO COMMUNICATIONS, LLC 13,000 (5.35%)

AMERICAN MESSAGING SERVICES, LLC 10,000 (4.12%)

TELSTAR COMMUNICATIONS INC 10,000 (4.12%)

IP HORIZON LLC 8,000 (3.29%)

AHOI LLC 6,000 (2.47%)

EXIANT COMMUNICATIONS LLC 5,000 (2.06%)

XO COLORADO, LLC 5,000 (2.06%)

FIVE9, INC. 3,000 (1.23%)

INTERLINK ADV SVC DBA FORETHOUGHT.NET - CO 3,000 (1.23%)

ALLO COMMUNICATIONS LLC 2,000 (0.82%)

Cities and Towns in Area Code 720

Allenspark, Colorado Bennett, Colorado Byers, Colorado Deckers, Colorado Deer Trail, Colorado Denver, Colorado Fort Lupton, Colorado Georgetown, Colorado Hudson, Colorado Keenesburg, Colorado Longmont, Colorado Roggen, Colorado Strasburg, Colorado

These geographic regions are also served by area codes 303 and 983.

How These Figures Were Built

These figures are estimates based on public phone-number assignment records. They are meant to show the likely mix of assigned phone numbers associated with area code 720, not live customer counts.

Some providers may have assigned phone numbers tied to this area code even if they do not actively market or sell service locally. These figures reflect public number-assignment records, not confirmed local service availability.

They also do not reflect number portability at the individual phone-number level, so some numbers may now be used on a different network or by a different provider than the original assignment records suggest.

Population data and locality matching provided by GeoNames.

Last refreshed: April 15, 2026 6:22 pm