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: 529

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-529 A Chicago Zone 01-Franklin IL CHCGILCLDSC  7421 AT&T - LOCAL 358      
312-529 0 Chicago Zone 01-Franklin IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-09-25   
312-529 1 Chicago Zone 01-Franklin IL CHCGILCLDSC  7421 AT&T - LOCAL 358      
312-529 2 Chicago Zone 01-Franklin IL CHCGILCLDSC  7421 AT&T - LOCAL 358      
312-529 3 Chicago Zone 01-Franklin IL CHCGILCLDSC  7421 AT&T - LOCAL 358      
312-529 4 Chicago Zone 01-Franklin IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358   2005-05-25   
312-529 5 Chicago Zone 01-Franklin IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358   2005-03-31   
312-529 6 Chicago Zone 01-Franklin IL CHCGILCLDSC  7421 AT&T - LOCAL 358      
312-529 7 Chicago Zone 01-Franklin IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2010-02-14   
312-529 8 Chicago Zone 01-Franklin IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-09-25   
312-529 9 Chicago Zone 01-Franklin IL CHCGILCLDSC  7421 AT&T - LOCAL 358      

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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