Area codes 303, 720 and 983 are telephone

area code A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, rea ...

s in the

North American Numbering Plan The North American Numbering Plan (NANP) is a telephone numbering plan for twenty-five regions in twenty countries, primarily in North America and the Caribbean. This group is historically known as World Zone 1 and has the international callin ...

for the north-central portion of the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sover ...

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...

. The numbering plan area comprises

Denver Denver () is a consolidated city and county, the capital, and most populous city of the U.S. state of Colorado. Its population was 715,522 at the 2020 census, a 19.22% increase since 2010. It is the 19th-most populous city in the Unit ...

and

Boulder In geology, a boulder (or rarely bowlder) is a rock fragment with size greater than in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive. In c ...

, as well as their surrounding suburbs, including Lakewood, Littleton,

Longmont The City of Longmont is a home rule municipality located in Boulder and Weld counties, Colorado, United States. Longmont is located northeast of the county seat of Boulder and north-northwest of the Colorado State Capitol in Denver. Longmont's ...

, Broomfield,

Aurora An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of bri ...

, and Castle Rock. Area code 303 is the original area code, while area codes 720 and 983 were added (1998, 2022 respectively) to form an

overlay plan Overlay may refer to: Computers *Overlay network, a computer network which is built on top of another network *Hardware overlay, one type of video overlay that uses memory dedicated to the application *Another term for exec, replacing one process ...

for the area, meaning that the same geographic service area is served by all area codes and that

ten-digit dialing Ten-digit dialing is a telephone dialing procedure in the countries and territories that are members of the North American Numbering Plan (NANP). It is the practice of including the area code of a telephone number when dialing to initiate a telep ...

is required for all calls made within the service area.

History

Area code 303 was one of the

original North American area codes The original North American area codes were established by the American Telephone & Telegraph Company (AT&T) in 1947, following the demonstration of regional Operator Toll Dialing during the World War II period. The program had the goal of speedin ...

of 1947, and originally served the entire state of Colorado. It remained the state's sole area code for 40 years. 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 Colorado, including

Colorado Springs Colorado Springs is a home rule municipality in, and the county seat of, El Paso County, Colorado, United States. It is the largest city in El Paso County, with a population of 478,961 at the 2020 United States Census, a 15.02% increase since ...

and

Pueblo In the Southwestern United States, Pueblo (capitalized) refers to the Native tribes of Puebloans having fixed-location communities with permanent buildings which also are called pueblos (lowercased). The Spanish explorers of northern New Spain ...

, was divided from the statewide area and received

area code 719 Area code 719 is a telephone area code in the North American Numbering Plan (NANP) for the state of Colorado. The numbering plan area includes Colorado Springs, Pueblo, Monument, Leadville, Alamosa, Monte Vista, the San Luis Valley, Cañon Cit ...

. Further demand for numbers led to another split: The northeastern and western portions of area code 303, including

Fort Collins A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ...

, Grand Junction,

Vail Vail is a home rule municipality in Eagle County, Colorado, United States. The population of the town was 4,835 in 2020. Home to Vail Ski Resort, the largest ski mountain in Colorado, the town is known for its hotels, dining, and for the numer ...

and

Aspen Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the ''Populus'' genus. Species These species are called aspens: *'' Populus adenopoda'' – Chinese aspen (China ...

, were separated on April 2, 1995, and became

area code 970 Area code 970 is a telephone area code in the North American Numbering Plan (NANP) serving most of the western and northern parts of Colorado. The numbering plan area includes Aspen, Breckenridge, Durango, Estes Park, Fort Collins, Glenwood Spri ...

. This split reduced 303 to the Denver-Boulder area. With the 1995 split, 303 was the only Colorado area code that did not border another state. 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

Front Range The Front Range is a mountain range of the Southern Rocky Mountains of North America located in the central portion of the U.S. State of Colorado, and southeastern portion of the U.S. State of Wyoming. It is the first mountain range encountere ...

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

overlay Overlay may refer to: Computers *Overlay network, a computer network which is built on top of another network *Hardware overlay, one type of video overlay that uses memory dedicated to the application *Another term for exec, replacing one process ...

. 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 303/720.NANPA
''NPA 983 and 303/720 All-Services Overlay (Colorado)''
Planning Letter PL-563 (2021-07-29) In early 2022, Area code 983 is in the network preparation stage, with first office code assignments scheduled not before June 17, 2022. In addition, no central office code in 983 may be installed before complete exhaustion of the existing area codes. The addition results in 23.8 million numbers being assigned to an area of about 3.5 million people.

Local calling

The numbering plan area is one of the largest toll-free calling zones in the western United States. With the exception of Roggen,

Brighton Brighton () is a seaside resort and one of the two main areas of the City of Brighton and Hove in the county of East Sussex, England. It is located south of London. Archaeological evidence of settlement in the area dates back to the Bronze A ...

, and

Wiggins Team Wiggins Le Col (), also known as ''Team Wiggins'' in media, was a professional developmental cycling team based in the United Kingdom, which began competing in elite road bicycle racing and track cycling in 2015. The team folded at the e ...

, no long-distance charges are levied for any calls made from one telephone to another in the area. With the exception of Roggen,

is mandatory in the area.

References

External links

Localcallingguide.com NPA 303Localcallingguide.com NPA 720
{{coord, 40, N, 105, W, scale:500000, display=title Telecommunications-related introductions in 1947 Telecommunications-related introductions in 1998

303 __NOTOC__ Year 303 ( CCCIII) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. It was known in the Roman Empire as the Year of the Consulship of Diocletian and Maximian (or, less frequently, y ...

Boulder, Colorado Denver metropolitan area

History

Local calling

See also

References

External links