Telephone Area 312. Page 4.
Prefix: +1312
This prefix is distributed within the state Illinois
The largest city in the region is Chicago
Time Zone: Central
Winter time: UTC-6
Summer time: UTC-5
Below on the map, there is indicated the largest city in the telephone area +1-312-...-.... Illinois Chicago.
Phone numbers +1-312-YYY-YYYY
| Company | District | Major City | Prefix |
|---|---|---|---|
| Ameritech Illinois | Cook | Chicago, IL | +1-312554-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312556-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312557-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312558-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312559-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312560-SSSS |
| Usa Mobility Wireless | Cook | Chicago, IL | +1-312562-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312563-SSSS |
| Cimco Communications | Chicago, IL | +1-312564-SSSS | |
| Ameritech Illinois | Cook | Chicago, IL | +1-312565-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312566-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312567-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312568-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312569-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312570-SSSS |
| Usa Mobility Wireless | Cook | Chicago, IL | +1-312571-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312572-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312573-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312574-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312575-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312576-SSSS |
| Mci Worldcom Communications | Cook | Chicago, IL | +1-312577-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312578-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312580-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312582-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312583-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312587-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312588-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312589-SSSS |
| Cellco Partnership DBA Verizon Wireless | Cook | Chicago, IL | +1-312590-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312591-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312592-SSSS |
| T-mobile Usa | Cook | Chicago, IL | +1-312593-SSSS |
| Mcimetro Access Transmission Services LLC | Chicago, IL | +1-312594-SSSS | |
| Ameritech Illinois | Cook | Chicago, IL | +1-312595-SSSS |
| Teleport Communications Group - Chicago | Cook | Chicago, IL | +1-312596-SSSS |
| Cook | +1-312597-SSSS | ||
| Usa Mobility Wireless | Cook | Chicago, IL | +1-312599-SSSS |
| Mcimetro Access Transmission Services LLC | Cook | Chicago, IL | +1-312601-SSSS |
| Broadwing Communications | Cook | Chicago, IL | +1-312602-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312603-SSSS |
| Xo Illinois | Cook | Chicago, IL | +1-312604-SSSS |
| Cook | +1-312605-SSSS | ||
| Ameritech Illinois | Cook | Chicago, IL | +1-312606-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312607-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312608-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312609-SSSS |
| Cook | +1-312610-SSSS | ||
| Ameritech Illinois | Cook | Chicago, IL | +1-312612-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312613-SSSS |
| Cook | +1-312614-SSSS | ||
| New Cingular Wireless PCS | Cook | Wheeling, IL | +1-312615-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312616-SSSS |
| Nextel Communications | Cook | Chicago, IL | +1-312617-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312618-SSSS |
| Cook | +1-312619-SSSS | ||
| Ameritech Illinois | Cook | Chicago, IL | +1-312621-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312622-SSSS |
| New Cingular Wireless PCS | Cook | Chicago, IL | +1-312623-SSSS |
| Rcn Telecom Services Of Illinois | Cook | Chicago, IL | +1-312624-SSSS |
| Global Naps | Cook | Chicago, IL | +1-312625-SSSS |
| Infotelecom | Chicago, IL | +1-312626-SSSS | |
| Ameritech Illinois | Cook | Chicago, IL | +1-312627-SSSS |
| Xo Illinois | Cook | Chicago, IL | +1-312628-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312629-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312630-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312632-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312633-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312634-SSSS |
| Global Crossing Local Services-il | Cook | Chicago, IL | +1-312635-SSSS |
| Cellco Partnership DBA Verizon Wireless | Cook | Chicago, IL | +1-312636-SSSS |
| Broadwing Communications | Cook | Chicago, IL | +1-312637-SSSS |
| Broadwing Communications | Cook | Chicago, IL | +1-312638-SSSS |
| Usa Mobility Wireless | Cook | Chicago, IL | +1-312639-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312640-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312641-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312642-SSSS |
| Rcn Telecom Services Of Illinois | Cook | Chicago, IL | +1-312643-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312644-SSSS |
| Ameritech Illinois | Cook | Chicago, IL | +1-312645-SSSS |
