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: 239

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-239 A Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      
312-239 0 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2004-11-08   
312-239 1 Chicago Zone 01-Canal IL CHCGILWUDS0  7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2006-10-23   
312-239 2 Chicago Zone 01-Canal IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS LLC - IL 358   2004-03-09   
312-239 3 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-06-14   
312-239 4 Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      
312-239 5 Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      
312-239 6 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-10-22   
312-239 7 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358   2005-12-12   
312-239 8 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-10-22   
312-239 9 Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      

Last updated: Fri, 13 May 2022 22:16:13 UTC

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