Local Calling Guide

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

NXX: 508

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-508 A Chicago Zone 01-Calumet IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358      
312-508 0 Chicago Zone 01-Calumet IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2012-06-06   
312-508 1 Chicago Zone 01-Calumet IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2012-06-06   
312-508 2 Chicago Zone 01-Calumet IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2012-06-22   
312-508 3 Chicago Zone 01-Calumet IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2012-05-10   
312-508 4 Chicago Zone 01-Calumet IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2012-05-10   
312-508 5 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2012-06-17   
312-508 6 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2012-06-17   
312-508 7 Chicago Zone 01-Calumet IL   400G CLEAR RATE COMMUNICATIONS, INC. - IL 358   2012-06-10   
312-508 8 Chicago Zone 01-Calumet IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2012-06-06   
312-508 9 Chicago Zone 01-Calumet IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2012-06-06   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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