Local Calling Guide

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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 361

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-361 A Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 0 Chicago Zone 01-Monroe IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-361 1 Chicago Zone 01-Monroe IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-07-14   
312-361 2 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 3 Chicago Zone 01-Monroe IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-07-14   
312-361 4 Chicago Zone 01-Monroe IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2011-06-23   
312-361 5 Chicago Zone 01-Monroe IL CHCGIL24DS6  224C ONVOY, LLC 358   2010-10-27   
312-361 6 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-361 7 Chicago Zone 01-Monroe IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2011-06-23   
312-361 8 Chicago Zone 01-Monroe IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-361 9 Chicago Zone 01-Monroe IL DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2010-10-27   

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

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