Area code 312 is a telephone area code in the North American Numbering Plan for the city of Chicago, including downtown, the Chicago Loop, and its immediate environs.

About area code 312: location, common spam callers, related area codes, and more. Includes 312 reverse phone lookup to identify spam callers.

Area code 312 is located in Illinois. Get the area’s map, cities covered, current time, prefixes, and dialing instructions.

To find information on a specific area code, use the area code lookup that makes it easy to find an area code by number and gives detailed information including city/state, timezone, and area …

Mar 9, 2025 · 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. …

Nov 1, 2025 · 312 Area Code located in Illinois, including 16 cities, 3 counties, 1 time zone, map, Census demographics, and 778 active prefixes.

Oct 22, 2025 · Accordingly, area code 312 is reserved for residents in Downtown Chicago and all residents in the 312 area code must dial the area code before the number even when making …

Oct 15, 2025 · Area code 312 is in Illinois, USA. Locate phone numbers 312-200-XXXX through 312-999-XXXX. City list with local time, map and overlaying areas.

Find 312 area code details including city, time zone, and map. Lookup area code 312 phone number, name, and location.

The 312 Area Code is located in the state of Illinois. Area Code 312 is one of the 269 three-digit telephone area codes in the USA. It covers roughly 7,859,286 unique phone numbers and …