Local Calling Guide

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

NXX: 600

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-600 A Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-600 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2014-05-24   
312-600 1 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-07-30   
312-600 2 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-07-30   
312-600 3 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2012-09-08   
312-600 4 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2012-09-08   
312-600 5 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2012-09-08   
312-600 6 Chicago Zone 01-Calumet IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2014-04-16   
312-600 7 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2012-09-08   
312-600 8 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2012-09-08   
312-600 9 Chicago Zone 01-Calumet IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2012-08-31   

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

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