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: 283

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-283 A Chicago Zone 01-Calumet IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 0 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 1 Chicago Zone 01-Calumet IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 2 Chicago Zone 01-Calumet IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2008-10-22   
312-283 3 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 4 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 5 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 6 Chicago Zone 01-Calumet IL   732J NUSO, LLC 358   2025-06-02   
312-283 7 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-283 8 Chicago Zone 01-Calumet IL   984E BANDWIDTH.COM CLEC, LLC - IL 358      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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