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Colorado's explosive growth in the second half of the 20th century, particularly in the Denver/Boulder area, made it a certainty that
Colorado would need another area code. An impending number shortage in the late 1980s meant this split could no longer be staved off. On March 5, 1988, southeastern
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In 2020, the North
American Numbering Plan Administrator estimated that the Denver metropolitan area would reach numbering exhaustion by 2023. Accordingly, the Colorado Public Utilities Commission approved on May 21, 2021 an additional area code for the all-services distributed overlay of NPA
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303/720. Area code 983 was activated on June 17, 2022. No central office codes in 983 were allowed to be installed before complete exhaustion of the previous area codes. This latest addition resulted in 23.8 million numbers being assigned to an area of about 3.5 million people.
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area is home not only to most of
Colorado's landlines, but also most of the state's cell phones, fax machines, and pagers. On September 1, 1998, area code 720 was instituted in the 303 service area to create an
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Although the 1995 split was intended as a long-term solution, the area continued to experience sharp growth so that within two years, further relief was necessary. The
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94:. Area code 303 is the original area code, while area codes 720 and 983 were added (in 1998 and 2022 respectively) to form an
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The numbering plan area is one of the largest toll-free calling zones in the western United States. With the exception of
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of 1947, and originally served the entire state of
Colorado. It remained the state's sole area code for 40 years.
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for the area, meaning that the same geographic service area is served by all area codes and that
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Clickable map of
Colorado area codes in blue (with bordering states).
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is required for all calls made within the service area.
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NPA 983 and 303/720 All-Services
Overlay (Colorado)
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525:Telecommunications-related introductions in 1998
520:Telecommunications-related introductions in 1947
201:List of North American Numbering Plan area codes
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146:, were separated on April 2, 1995, and became
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333:"Denver's new area code starts in 2022"
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322:, Planning Letter PL-563 (2021-07-29)
54:for the north-central portion of the
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291:2020-1 NRUF and NPA Exhaust Analysis
62:. The numbering plan area comprises
268:"10-Digit Dialing Hits Denver Area"
266:MICHAEL LOVELL (August 31, 1998).
254:NANPA Information Letter 94/09-012
244:(1987-03-27), retrieved 2020-08-29
112:original North American area codes
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354:"Colorado Counties by Population"
256:(1994-09-21) retrieved 2020-08-29
242:NANP Information Letter 87-03-045
535:Area codes in the United States
1:
397:Localcallingguide.com NPA 720
392:Localcallingguide.com NPA 303
110:Area code 303 was one of the
52:North American Numbering Plan
16:Colorado telephone area codes
196:List of Colorado area codes
44:Area codes 303, 720 and 983
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221:"Area Codes Map, Colorado"
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545:Denver metropolitan area
530:Area codes in Colorado
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368:"Local Calling Guide"
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118:Colorado, including
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540:Boulder, Colorado
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100:ten-digit dialing
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120:Colorado Springs
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386:External links
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136:Grand Junction
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46:are telephone
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170:Local calling
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148:area code 970
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128:area code 719
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406:area codes:
371:. Retrieved
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132:Fort Collins
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408:303/720/983
155:Front Range
92:Castle Rock
514:Categories
496:40°N 105°W
207:References
84:Broomfield
56:U.S. state
48:area codes
270:. Reuters
227:April 24,
76:Littleton
501:40; -105
404:Colorado
274:June 10,
190:See also
180:Brighton
80:Longmont
72:Lakewood
60:Colorado
338:May 27,
316:NANPA,
223:. NANPA
184:Wiggins
160:overlay
106:History
68:Boulder
50:in the
300:May 9,
182:, and
176:Roggen
124:Pueblo
90:, and
88:Aurora
64:Denver
487:105°W
465:South
425:North
295:(PDF)
144:Aspen
484:40°N
452:East
438:West
375:2012
340:2021
302:2021
276:2019
229:2018
142:and
140:Vail
122:and
66:and
469:719
456:719
442:970
429:970
416:970
412:719
162:.
86:,
58:of
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309:^
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