What area code is 312?
Here's everything about it.
Instant lookup for the 312 area code — location, time zone, cities served, and who's been calling from it. No sign-up, no app.
312 at a glance
SummaryCities served by 312
Chicago (Loop)Where 312 sits on the map
Overlay: 872Coverage area
Why is there a 872 overlay?
312 ran out of new number combinations as the region grew, so the 872 area code was added over the same geographic area. New lines get either code — both are local calls to each other, and 10-digit dialing is required throughout the region.
Who called me from 312?
Community reportsFrequently asked questions
FAQWhat area code is 312?+–
312 covers central Chicago including the Loop, one of the original 1947 area codes.
Where is area code 312 located?+–
It covers Cook and the surrounding area, including Chicago, The Loop, Near North Side in Illinois.
What time zone is 312?+–
312 observes Central (CT), which is UTC−6 / −5 DST and follows daylight saving time.
Is 312 the same as 872?+–
872 is an overlay code covering the same geographic area as 312. They are not interchangeable numbers, but calls between them are local.
Can I get a 312 phone number?+–
Yes — most mobile carriers and VoIP providers let you request a 312 number regardless of where you physically live.