Local Calling Guide

Area code/prefix search

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

NXX: 373

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-373 A Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-373 1 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 2 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 3 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 4 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 5 Chicago Zone 01-Calumet IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-373 6 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 7 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 8 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-373 9 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      

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

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