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:

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-379 A Chicago Zone 01-Illinois Dearborn IL CHCGILWUDS0  7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358      
312-379 0 Chicago Zone 01-Illinois Dearborn IL   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358      
312-379 1 Chicago Zone 01-Illinois Dearborn IL   9329 AMERITECH ILLINOIS 358   2002-06-03   
312-379 2 Chicago Zone 01-Illinois Dearborn IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-379 3 Chicago Zone 01-Illinois Dearborn IL   4604 FIRST COMMUNICATIONS LLC - IL 358   2005-02-24   
312-379 4 Chicago Zone 01-Illinois Dearborn IL   9329 AMERITECH ILLINOIS 358   2000-05-05   
312-379 5 Chicago Zone 01-Illinois Dearborn IL   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358      
312-379 6 Chicago Zone 01-Illinois Dearborn IL   9329 AMERITECH ILLINOIS 358   2000-05-05   
312-379 7 Chicago Zone 01-Illinois Dearborn IL   9329 AMERITECH ILLINOIS 358   2000-05-05   
312-379 8 Chicago Zone 01-Illinois Dearborn IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-379 9 Chicago Zone 01-Illinois Dearborn IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-02-25   

Last updated: Sun, 10 Nov 2019 13:49:34 UTC

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