Geographic Regions and Area Codes in Area Code 309

Area Code 309 is located in the state of Illinois and covers a significant portion of west-central Illinois. It includes major cities such as Peoria, Bloomington, Normal, Moline, and Rock Island. The area code spans 20 counties, including Peoria County, McLean County, Rock Island County, Tazewell County, and Henry County. Additionally, it serves several metropolitan areas, including the Peoria-Bloomington area and the Davenport-Rock Island-Moline area. Area Code 309 has a single overlay, Area Code 861, which serves the same geographic region. It also borders several other area codes, including 217, 319, 331/630, 563, 573, and 779/815.