Area Code 618 Location

Area code 618 serves Alton and the wider Metro East region of southern Illinois, stretching along the Mississippi River and across much of the state’s southern tier. It includes historic river towns, college communities, and rural areas, making it a key phone area for both local life and cross-river connections to St. Louis. Alton sits at the meeting point of major waterways and is known for the Great River Road, the Piasa Bird bluff painting, and the Melvin Price Locks and Dam with the National Great Rivers Museum. Area code 618 was established in 1947, making it one of Illinois’s oldest telephone codes.

• Major communities in 618 include: Alton, Belleville, East St. Louis, Edwardsville, Granite City, Collinsville, O’Fallon, Fairview Heights, Carbondale (home to Southern Illinois University), Marion, Mount Vernon, Centralia, Cairo, and Metropolis.
• Landmarks and attractions covered by 618: Cahokia Mounds State Historic Site (UNESCO World Heritage Site near Collinsville), Shawnee National Forest in far southern Illinois, and the scenic Great River Road along the Mississippi.

Today, 618 works alongside the newer overlay area code 730, so 10‑digit dialing is standard across the region. This area code anchors much of southern Illinois, from college life in Carbondale to government and business centers in Belleville and Edwardsville. It also supports busy freight and travel corridors near the Mississippi River bridges, helping connect Metro East communities with the St. Louis area while keeping local numbers familiar and easy to recognize.

“Area code 618 was established in 1947.” — North American Numbering Plan Administrator (NANPA)