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: 517

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-517 A Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-517 0 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2016-07-16   
312-517 1 Chicago Zone 01-Calumet IL CHCGILDTDS3  5447 ACCESS ONE, INC. - IL 358   2015-11-25   
312-517 2 Chicago Zone 01-Calumet IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2017-03-26   
312-517 3 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2015-03-26   
312-517 4 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2015-03-26   
312-517 5 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2015-03-27   
312-517 6 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2015-03-27   
312-517 7 Chicago Zone 01-Calumet IL CHCGILWUX1X  7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2015-03-27   
312-517 8 Chicago Zone 01-Calumet IL CHCGILWUX1X  7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2015-03-27   
312-517 9 Chicago Zone 01-Calumet IL CHCGILDT8MD  508J CENTURYLINK COMMUNICATIONS, LLC 358   2015-03-27   

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

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