Find any 303- phone number in Colorado

The 303 area code is the Colorado area code serving the Denver-Aurora Metropolitan area, as well as many other cities and towns in the Colorado Front Range. It was created in 1947 as one of the original area codes established by the North American Numbering Plan (NANP), which was established to provide reliable dial phone service in North America.

The 303 area code is part of the NANP, which is a system for assigning area codes to each geographic region in the United States, Canada, and some Caribbean nations. Each area code is a three-digit code representing a particular area, like 303 for Denver. This system allows people to more easily identify the location of a phone number by the area code alone. When an area becomes busy due to an increase in telephone subscribers, additional area codes are created to handle the additional demand. In 1988, the 303 area code was split to form the 720 area code and again in 1998 to form the 970 area code.