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: 300

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-300 A Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-300 0 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2018-10-25   
312-300 1 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-02-21   
312-300 2 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-02-21   
312-300 3 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-02-21   
312-300 4 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2012-02-25   
312-300 5 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2012-02-25   
312-300 6 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2012-02-25   
312-300 7 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2012-02-25   
312-300 8 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-02-21   
312-300 9 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-02-21   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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