Area code · IL
312 area code
The 312 area code serves Chicago, Illinois. Look up a specific 312 number, or browse other popular area codes.
2 min readUpdated October 6, 2026By the SecondBars team
Location
Chicago, IL
Timezone
Central
State
Illinois
Major cities
Downtown Chicago
ABOUTAbout the 312 area code
The 312 area code is assigned to Chicago, Illinois. Phone numbers with this area code are used by residents and businesses in the Chicago metropolitan area and surrounding communities.
If you've received an unwanted call from a 312 area code number, use the phone lookup to see what we have on file for it. Don't call back numbers you don't recognize or share personal details, and block numbers that keep calling.
EXPLOREPopular area codes
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