Find any 303- phone number in Colorado
The 303 area code is part of the North American numbering plan that designates area codes throughout the United States, Canada, and certain Caribbean nations. It serves most of the state of Colorado, specifically the Denver-Boulder-Greeley metropolitan area and the Front Range corridor. The 303 area code is one of the original area codes established in 1947, which have since been supplemented by over 300 other North American area codes to meet the growing demands for telecommunication services.
The North American Numbering Plan is a three-digit numbering system mandated by the Federal Communications Commission that creates distinct addressing and routing for each telephone user. Every single telephone subscriber within the 303 area code is assigned a unique seven digit phone number, which includes the three digit area code. When a cell phone caller dials a local number within their area code, they need to follow the established dialing patterns, which mean they must include the leading "1" before entering their 10 digit number. When a caller goes outside of their own area code, they must first dial a "1" to indicate it is a long-distance call, and then enter the area code followed by the seven-digit number.