Local Calling Guide

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

NXX: 283

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-283 A Chicago Zone 01-Franklin IL CHCGILCNDS1  8709 GLOBAL CROSSING LOCAL SERVICES, INC. - IL 358      
312-283 0 Chicago Zone 01-Franklin IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 1 Chicago Zone 01-Franklin IL CHCGILCNDS1  8709 GLOBAL CROSSING LOCAL SERVICES, INC. - IL 358      
312-283 2 Chicago Zone 01-Franklin IL CHCGILWUX1X  4717 PAETEC COMMUNICATIONS, INC. - IL 358   2008-10-22   
312-283 3 Chicago Zone 01-Franklin IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 4 Chicago Zone 01-Franklin IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 5 Chicago Zone 01-Franklin IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 6 Chicago Zone 01-Franklin IL CHCGILCNDS1  8709 GLOBAL CROSSING LOCAL SERVICES, INC. - IL 358      
312-283 7 Chicago Zone 01-Franklin IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 8 Chicago Zone 01-Franklin IL CHCGILCNDS1  8709 GLOBAL CROSSING LOCAL SERVICES, INC. - IL 358      
312-283 9 Chicago Zone 01-Franklin IL CHCGILCNDS1  8709 GLOBAL CROSSING LOCAL SERVICES, INC. - IL 358      

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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