Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 638

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-638 A Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 0 Chicago Zone 01-Calumet IL CHCGILCNHMD  073H TELNYX LLC 358   2022-08-25   
312-638 1 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 2 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 3 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 4 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 5 Chicago Zone 01-Calumet IL CHCGILCPDS9  138G LEVEL 3 TELECOM OF ILLINOIS, LLC - IL 358   2015-04-24   
312-638 6 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 7 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 8 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-638 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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