312 Area Code: Chicago (the Loop)
Updated: November 2026. Area code data: NANPA assignments via Simple Wikipedia and areacode.fyi, checked November 2026.
It covers downtown Chicago (the Loop). The rest of the city uses 773, and 872 overlays both.
| Area code | 312 |
|---|---|
| Location | Chicago (the Loop) |
| Time zone | Central Time |
| Type | Geographic |
| In service since | 1947 |
| Region | Illinois |
Where is 312?
Chicago (the Loop). It covers downtown Chicago (the Loop). The rest of the city uses 773, and 872 overlays both.
Time zone
Area code 312 is in the Central Time zone. The best time to call is generally between 9 a.m. and 8 p.m. local time. Use our best time to call tool to compare it with your own time.
History
312 is one of the original 1947 area codes for Chicago. In 1996 the area outside the Loop was split off into 773, and the overlay 872 was added in 2009.
How to dial 312
From the United States or Canada, dial 1 + 312 + the 7-digit number. From abroad, dial your international prefix, then 1 + 312 + the number — for example, +1 312 555 0132.
Is a call from 312 a scam?
Scammers can fake any area code, including 312. A number that looks local is not proof of who is calling. Never share passwords, verification codes or payment details with an unexpected caller; hang up and call the company back on a number from its official website. Report scam calls at reportfraud.ftc.gov, and forward spam texts to 7726.
Report scam calls at reportfraud.ftc.gov, forward spam texts to 7726, and register on the National Do Not Call Registry at donotcall.gov.
Nearby area codes
FAQs
What city is area code 312?
Chicago (the Loop).
What time zone is area code 312?
Central Time.
Is 312 a toll-free area code?
No. 312 is a regular geographic area code, so calls to it are charged at your normal rate.
How do I call a 312 number from abroad?
Dial your international prefix, then 1 + 312 + the 7-digit number — for example, +1 312 555 0132.
Should I call back an unknown 312 number?
Only if you are expecting the call. If you do not recognise the number, look the company up independently instead of calling back — scammers often hope a callback will connect you to a premium-rate or phishing line.
← Browse all area codes by state · Free phone number tools →