618 Area Code
Area code 618 is one of the original 86 area codes created by AT&T and the Bell System in 1947. It originally served southern Illinois including East St. Louis and Carbondale. To avoid exhausting all possible phone numbers in this area code, relief planning has begun. It is considered, "in jeopardy" which means that it is possible that the supply of numbers could be exhausted before an overlay can be created or the area code splits. Currently, the largest city it serves is Belleville, IL, and it overlaps coverage areas with area code 730.