Active Prefixes in Area Code 312
| Prefix | Primary City | Phone Type | Company |
|---|---|---|---|
| 312-295-#### | La Grange Park | Wireless Numbers | Usa Mobility Wireles... |
| 312-296-#### | Chicago | Wireless Numbers | Sprint Spectrum L.p.... |
| 312-297-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-298-#### | Chicago | Landline Numbers | Sigecom, Llc - Il... |
| 312-299-#### | Chicago | Wireless Numbers | Usa Mobility Wireles... |
| 312-300-#### | Chicago | Landline Numbers | Net Talk.com, Inc. -... |
| 312-301-#### | Hinsdale | Wireless Numbers | New Cingular Wireles... |
| 312-302-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-303-#### | Wheeling | Wireless Numbers | New Cingular Wireles... |
| 312-304-#### | Hinsdale | Wireless Numbers | New Cingular Wireles... |
| 312-305-#### | Northbrook | Wireless Numbers | Cellco Partnership D... |
| 312-306-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-307-#### | Chicago | Wireless Numbers | New Cingular Wireles... |
| 312-308-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-309-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-310-#### | Northbrook | Wireless Numbers | Cellco Partnership D... |
| 312-314-#### | Hinsdale | Wireless Numbers | New Cingular Wireles... |
| 312-315-#### | Chicago | Wireless Numbers | New Cingular Wireles... |
| 312-316-#### | Chicago | Wireless Numbers | New Cingular Wireles... |
| 312-317-#### | Wheeling | Wireless Numbers | New Cingular Wireles... |
| 312-318-#### | La Grange Park | Wireless Numbers | Cellco Partnership D... |
| 312-320-#### | Chicago | Wireless Numbers | New Cingular Wireles... |
| 312-321-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-322-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-323-#### | Chicago | Landline Numbers | American Messaging (... |
| 312-324-#### | Chicago | Landline Numbers | Level 3 Communicatio... |
| 312-325-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-326-#### | Chicago | Landline Numbers | Ameritech Illinois... |
| 312-327-#### | Chicago | Landline Numbers | Xo Illinois, Inc.... |
| 312-328-#### | Chicago | Landline Numbers | Ameritech Illinois... |
Area Code 312 Introduction
| Area Code: | 312 |
| Country: | United States |
| State/Province: | Illinois - IL |
| Major City: | Chicago |
| Time Zone: | Central |
| Average property | $157K |
| Average age | 59 y/o |
| Average assets | $89.3K |
| Population density | 57,914 sq mi (149,932 km2) |
| Population | 12,801,539 |
| latitude Longitude: | |
| 36° 58′ N to 42° 30′ N / 87° 30′ W to 91° 31′ W | |
| About 312 : | |
| The 312 Area Code (or Area Code 312) is located in the state of MO. Area Code 312 is one of the 269 3-digit telephone area codes in the USA. It covers roughly 1.63 million unique phone numbers and 5.08 million individuals near the city of Saint Louis Area code 312 was put into service. In 1989 Area code 312 was split to form area code 708. In 1996 area code 312 was split again to form area code 773. In 2009 area code 312 was overlaid with area code 872. |
|
| Major cities or places | |
| Chicago, IL | |