Local Calling Guide

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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 741

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-741 A Chicago Zone 01-Calumet IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2024-12-09   
312-741 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-06-01   
312-741 1 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-06-01   
312-741 2 Chicago Zone 01-Calumet IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2017-12-22   
312-741 3 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-06-01   
312-741 4 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-06-01   
312-741 5 Chicago Zone 01-Calumet IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2017-12-22   
312-741 6 Chicago Zone 01-Calumet IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2019-06-20   
312-741 7 Chicago Zone 01-Calumet IL OKBRILOAXEX  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2018-09-24   
312-741 8 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2018-10-15   
312-741 9 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2018-12-20   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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