What is 815 area code?

The 815 area code is located in the northern part of Illinois and covers cities such as Rockford, Joliet, and Kankakee. It was one of the original area codes established in 1947 as part of the North American Numbering Plan. The 815 area code currently serves a large portion of north-central Illinois and is one of the most populous area codes in the state.

As of 2021, the 815 area code is overlaid with the 779 area code, meaning that new phone numbers in the region may be assigned either a 815 or 779 area code. This overlay was implemented in 2007 due to a high demand for phone numbers in the region.

The 815 area code is known for its diverse mix of urban and rural communities, as well as its strong industrial and agricultural presence. It is home to a number of major cities, colleges, and cultural attractions, making it a vibrant and dynamic region of Illinois.