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: 566

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-566 A Chicago Zone 01-Wabash IL CHCGILWBDS2  9329 ILLINOIS BELL TEL CO 358      
312-566 0 Chicago Zone 01-Wabash IL CHCGILWBDS2  9329 ILLINOIS BELL TEL CO 358      
312-566 1 Chicago Zone 01-Wabash IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2009-01-27   
312-566 2 Chicago Zone 01-Wabash IL CHCGILWBDS2  9329 ILLINOIS BELL TEL CO 358      
312-566 3 Chicago Zone 01-Wabash IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-13   
312-566 4 Chicago Zone 01-Wabash IL CHCGILDTDS3  5447 ACCESS ONE, INC. - IL 358   2014-05-10   
312-566 5 Chicago Zone 01-Wabash IL CHCGILWBDS2  9329 ILLINOIS BELL TEL CO 358      
312-566 6 Chicago Zone 01-Wabash IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2009-01-27   
312-566 7 Chicago Zone 01-Wabash IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-566 8 Chicago Zone 01-Wabash IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-566 9 Chicago Zone 01-Wabash IL CHCGILWBDS2  9329 ILLINOIS BELL TEL CO 358      

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

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