Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 912

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-912 A Chicago Zone 01-Canal IL CHCGILCLDS0  9329 ILLINOIS BELL TEL CO 358      
312-912 0 Chicago Zone 01-Canal IL CHCGIL24DS6  224C ONVOY, LLC 358   2016-02-15   
312-912 1 Chicago Zone 01-Canal IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2006-11-15   
312-912 2 Chicago Zone 01-Canal IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2007-05-30   
312-912 3 Chicago Zone 01-Canal IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2007-05-30   
312-912 4 Chicago Zone 01-Canal IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2007-10-17   
312-912 5 Chicago Zone 01-Canal IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2007-10-17   
312-912 6 Chicago Zone 01-Canal IL CHCGILWUX6X  460K FIRST COMMUNICATIONS, LLC 358   2010-10-15   
312-912 7 Chicago Zone 01-Canal IL CHCGIL24DS6  224C ONVOY, LLC 358   2008-08-29   
312-912 8 Chicago Zone 01-Canal IL CHCGIL24DS6  224C ONVOY, LLC 358   2008-08-29   
312-912 9 Chicago Zone 01-Canal IL CHCGIL24DS6  224C ONVOY, LLC 358   2008-08-29   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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