Find any 779- phone number in Illinois

The 779 area code is an overlay to the 815 area code in Illinois. This area code was established in 2009 to meet the growing demand for phone numbers in the state. It covers the northwestern corner of the Chicago metropolitan area, including the cities of Crystal Lake, DeKalb, Kankakee, Rockford, and Mississauga. The 779 area code also covers the following counties: Boone, Jo Daviess, Lee, Ogle, Winnebago, Carroll, and Stephenson.

The 779 area code is part of the North American Numbering Plan (NANP), which is a system of assigning telephone numbers to telecommunication users in Canada, the United States and some Caribbean countries. Under the plan, each area code is made up of 3 digits and each phone number is made up of 10 digits. The NANP is administered by a federal agency known as the North American Numbering Plan Administration (NANPA). This agency is responsible for assigning area codes and implementing NANP regulations throughout the United States. The NANPA database also keeps track of all numbers in use within the NANP area.