People search by name, phone, address or email. Browse post history.

Banner Phone Directory

 

The 303 area code is one of the four numbering plan areas assigned to Colorado State. This prefix surrounds the central side of the region and is overlaid by the prefix 720, which covers the same service area. 

Currently, this prefix is the most populous area code of the Colorado telephonic network serving over 2.9 million users that represent nearly half of the state. In this way, the 303 area code symbolizes a pillar for the telecommunication system of Colorado and contributes to the development of its economic sector. 

On the other hand, the 303 area code runs in the Denver metropolitan area and provides service to 12 of the 64 Colorado counties; such as Boulder, Jefferson, Denver, Douglas, and Adam. 

Denver

1. History

The 303 area code began running in October 1947, when the Bell System put in service the North American Numbering Plan (NANP), assigned to the territories of Canada, and the U.S. With the activation of this project, Colorado State received the 303 prefixes as the only codification for the entire region. 

In the second half of the 20th century, Colorado presented a massive growth in its population, particularly in the Denver area. However, the 303 area code remained as the only state codification for nearly 40 years. 

On March 5, 1988, the Colorado public commission decided to activate the second dialing number of the network. For this reason, the 719 area code started running, surrounding the southeastern portion of the state; including Colorado Springs and Pueblo. 

By 1995, the prefix 303 was split again, opened the way for the code 970 that obtained the municipalities of Fort Collins, Grand Junction, Vail, and Aspen. This second division reduced the 303 area code to the Denver metro area. On September 1, 1998, the authorities designated the codification 720, which becomes the first overlay plan of Colorado. 

2. Location

Located in the western region of the country, Colorado encloses most of the Southern Rocky Mountains and the western edge of the Great Plains. At the moment, it stands out as the 21st most populous city with around 5.8 million people. Moreover, in terms of the territory, it disposes of 104,094 square miles, being the eighth largest state of the U.S. 

On the other hand, The Greatest urban area of the state is the Denver metropolitan region consisting of the six central Colorado counties of Adams, Arapahoe, Broomfield, Denver, Douglas, and Jefferson. This region encompasses over 2.8 million inhabitants, being the 19th most populous metropolitan statistical area of the country. 

Just like the whole state, the 303 area code corresponds to the Mountain Time zone. Its postal service is compounded by 209 non-unique postal area zip codes and encloses 6697.11 square miles. 

Adjacent codes

As we mentioned before, Colorado disposes of four dialing codes, being the most recently added to the network the prefix 720, which overlaps the 303 area code. 

The 719 area code is the second state’s codification installed in 1988. It is the only dialing number of its service area and covers 26 counties including El Paso, Pueblo, Fremont, and Teller. 

The last state’s prefix is the 970 area code assigned to the north and western portions of Colorado and the surrounding 31 counties. 

3. Most Important Locations in the 303 Area Code

Denver

Consolidated as an official city-county, Denver lies on the western edge of the Great Plains, just east of the Front Range of the Rocky Mountains. This territory is only bordered by three counties, Adams to the north and east, Arapahoe to south and east, and Jefferson to the west. 

Located nearly one mile above sea level, it is commonly referred to as the "Mile-High City". Being the capital and most populous city of the state, Denver encloses nearly 154.92 square miles and encompasses more than 705k inhabitants. 

Today Denver is a beta world city with a significant influence in the economic sector of the country. Covered by the prefixes 303 and 720 it disposes of 71 non-unique zip codes.  

Lakewood

Situated in Jefferson County, Lakewood is the fifth-most populous city of Colorado, with an estimated population of around 155k residents. Being one of the main cities of the Denver metro area, it stands out as the major municipality of the Front Range Urban Corridor.

Founded in 1889 and incorporated in 1969, Lakewood is located immediately west of Denver on the western edge of the Great Plains. Also, it is home to several small lakes and rivers, such as the Soda and the Bear Creek Lakes

Covering a total area of 44.22 square miles, Lakewood owns 11 non-unique zip codes; including 80123, 80214, 80215, 80226, 80227, and 80401. 

  

4. Other Important Districts and ZIP Codes of the 303 Area Code

12 of the 64 counties of Colorado are covered by the 303 area code: 

 

  • Arapahoe County: founded on November 1, 1861, and named for the Arapaho Native American tribe, this county belongs to the Denver metro area. Being the third most populous county of Colorado, it encompasses over 644k residents and disposes of 30 zip codes

 

  • Jefferson County: with an estimated population of about 574k inhabitants, Jefferson is the fourth-most populous county of Colorado. Known as the "Gateway to the Rocky Mountains", it covers nearly 774square miles and disposes of 35 zip codes

 

  • Douglas County: settledon  November 1, 1861, Douglas is located midway between Colorado Springs and Denver. Being one of the largest territories of the state it surrounds a total area of 843 square miles and encloses 336k Its county seat is Castle Rock and owns 15 zip codes

Main Postal and Shipping Services

  • US Post Office, Denver, CO, - +1 303-333-7094
  • USPS Capitol Hill Annex, Denver, CO, - +1 303-860-7954
  • A+ Mail Room, Aurora, CO, - +1 303-755-6245
  • UPS Customer Center, Aurora, CO, - +1 303-742-5877

5. FAQs

How many area codes are there in Denver?

At the time, Denver disposes of 2 numbering plan areas, the 303 and 720 area codes.

How many overlay plans are there in Colorado?

The only overlay plan existing in the state is the 720 area code that surrounds the prefix 303.