Area codes 618 and 730

Area codes 618 and 730 are telephone area codes in the North American Numbering Plan (NANP) for southern Illinois. The numbering plan area (NPA) comprises one hundred and twenty-six municipalities, such as Carbondale, Cairo, Belleville, East St. Louis, Edwardsville, Marion, O'Fallon, Alton, Mt. Vernon, Centralia, Herrin, Salem, Metropolis, Fairview Heights, Collinsville, and Granite City. Area code 618 was one of the original North American area codes created in 1947, and 730 was added to the plan area to form an overlay complex to satisfy the need for more telephone numbers in the region. The current population of the 618/730 area code is 1,288,816 people.^[1] It encompasses approximately 15,458 square mile (9,893,120 acres); and has a population density of 83.38 people per square mile.