Local Calling Guide

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

NXX: 503

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-503 A Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 0 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 1 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 2 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 3 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 4 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 5 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 6 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 7 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 8 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-503 9 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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