District of Illinois area codes: 312 | |
---|---|
Country | United States |
State/Province | Illinois |
Major City | Chicago |
Time Zone | Central (UTC-06:00) |
Prefix | County | Primary City | Company |
---|---|---|---|
312-201 | Cook | Chicago, IL | Ameritech Illinois |
312-202 | Cook | Chicago, IL | Ameritech Illinois |
312-203 | Cook | Chicago, IL | New Cingular Wireless PCS |
312-204 | Cook | Chicago, IL | Ameritech Illinois |
312-205 | Cook | Chicago, IL | Allegiance Telecom |
312-206 | Cook | Chicago, IL | New Cingular Wireless PCS |
312-207 | Cook | Chicago, IL | Ameritech Illinois |
312-208 | Cook | Chicago, IL | New Cingular Wireless PCS |
312-209 | Cook | Northbrook, IL | Cellco Partnership DBA Verizon Wireless |
312-212 | Cook | Chicago, IL | Ameritech Illinois |
312-213 | Cook | Chicago, IL | New Cingular Wireless PCS |
312-214 | Cook | Chicago, IL | Ameritech Illinois |
312-215 | Cook | Wheeling, IL | New Cingular Wireless PCS |
312-216 | Cook | Chicago, IL | First Communications LLC |
312-217 | Cook | Chicago, IL | United States Cellular Corp. - Illinois |
312-218 | Cook | Chicago, IL | New Cingular Wireless PCS |
312-219 | Cook | Chicago, IL | Bandwidth.com Clec |
312-220 | Cook | Chicago, IL | Ameritech Illinois |
312-221 | Cook | Chicago, IL | Sprint Spectrum L.p. |
312-222 | Cook | Chicago, IL | Ameritech Illinois |
There are 701 prefixes, In the code area, the major cities are Chicago, IL. The major city is Chicago.