Basically, it involves Common Interests and Common Needs. The telecommunications industry also looks at dialing patterns to identify communities of interest. An area code reaches exhaust whan all of the telephone prefixes within that area code are assigned. The FCC has ultimate jurisdiction over telephone number administration. The exhausting area code is split into two or more geographic areas, leaving the existing area code to serve one side of the geographic area and assigning new area codes to the remaining areas.
Growth is measured in the demand for telephone numbers.
Local Number Portability has been introduced in many cities throughout the country. It enables consumers to change local telephone companies without having to change their telephone numbers. The FCC receives advice on number administration issues from the North American Numbering Council, an advisory body made up of industry participants, consumer advocates, and state regulators. The North American Numbering Plan Administrator is responsible for day to day administration, assignment and management of area codes in the United States. NeuStar, Inc. is responsible for the administration of the North American Numbering Plan.