| General Information about Area Code 312 | |
|---|---|
| Country | United States |
| State / Province / Territory | Illinois |
| Major City | Chicago |
| Time Zone | Central (UTC-06:00) |
| Prefix | Primary City | County | Phone Type |
|---|---|---|---|
| 312-324 | Chicago | Cook | Landline |
| 312-393 | Chicago | Cook | Wireless |
| 312-571 | Chicago | Cook | Wireless |
| 312-927 | Chicago | Cook | Wireless |
| 312-752 | Chicago | Cook | Landline |
| 312-603 | Chicago | Cook | Landline |
| 312-701 | Chicago | Cook | Landline |
| 312-494 | Chicago | Cook | Landline |
| 312-509 | Chicago | Cook | Landline |
| 312-462 | Chicago | Cook | Landline |
| 312-716 | Chicago | Cook | Wireless |
| 312-485 | Chicago | Cook | Wireless |
| 312-697 | Chicago | Cook | Landline |
| 312-499 | Chicago | Cook | Landline |
| 312-923 | Chicago | Cook | Landline |
| 312-966 | Chicago | Cook | Wireless |
| 312-553 | Chicago | Cook | Landline |
| 312-960 | Chicago | Cook | Landline |
| 312-917 | Chicago | Cook | Landline |
| 312-846 | Chicago | Cook | Landline |