309/861: Central-Western Illinois including Bloomington–Normal, Peoria, and all the way west to the Illinois part of the Quad Cities including Moline, and Rock Island. 312: Chicago, the central city area including the Chicago Loop and the Near North Side.

It has the following active area codes: List of all area codes in Chicago, IL. Chicago, IL area code map, list, and phone lookup.

Our area code lookup makes it easy to find area codes in Illinois. Includes area code listings of all Illinois area codes with corresponding cities.

Lookup area code information for CHICAGO, IL. Get the NPA NXX (area code and prefix) as well as much more data for CHICAGO, IL.

View the 312 area code map in Illinois. Find the name of any phone number in area code 312.

Just enter the area code in the search box to see a map of an individual area code plus the time zone, current time, history, and more. Area code maps for all of the U.S. area codes. View the entire US or select an area code to see a detailed map.

2025年1月1日 · Area Code 312 is located in Illinois. It covers 16 cities, including Chicago, Cicero, Schaumburg, Glenview, and Buffalo Grove. It also covers 3 counties, including Cook County, Lake County, Dupage County. A full list of covered cities and counties is below including its prefix and population coverage.

2025年1月1日 · Area Code 630 is located in Illinois. It covers 61 cities, including Chicago, Aurora, Naperville, Elgin, and Schaumburg. It also covers 6 counties, including Dupage County, Cook County, Kane County, Kendall County, and Lake County. A full list of covered cities and counties is below including its prefix and population coverage.

Illinois area codes map gives information about all the area codes of Illinois state along with their counties list.

312 is an area code located in the state of Illinois, US. The largest city it serves is Chicago. Find out where 312 area code zone from, which states, counties and cities it covers. Get the most exact information on time zones here.