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: 736

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-736 A Chicago Zone 01-Calumet IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-736 0 Chicago Zone 01-Calumet IL CHCGILWUJMD  073H TELNYX LLC 358   2018-07-05   
312-736 1 Chicago Zone 01-Calumet IL CHCGILDTDS3  5447 ACCESS ONE, INC. - IL 358   2018-03-16   
312-736 2 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-07-26   
312-736 3 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2018-08-17   
312-736 4 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2018-08-17   
312-736 5 Chicago Zone 01-Calumet IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2017-12-22   
312-736 6 Chicago Zone 01-Calumet IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2017-12-22   
312-736 7 Chicago Zone 01-Calumet IL CHCGILWUJMD  073H TELNYX LLC 358   2018-11-14   
312-736 8 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-07-26   
312-736 9 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2019-02-16   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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