Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 999

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-999 A Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358      
312-999 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-08-14   
312-999 1 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-12-02   
312-999 2 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-12-02   
312-999 3 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-12-02   
312-999 4 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-12-02   
312-999 5 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-12-02   
312-999 6 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-12-02   
312-999 7 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-08-14   
312-999 8 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-08-14   
312-999 9 Chicago Zone 01-Calumet IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358   2014-01-02   

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

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