Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Chicago Zone 01-Illinois Dearborn, IL

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
312-205 A CHCHILLEDS0  8950 ALLEGIANCE TELECOM, INC. - IL 358      
312-222 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-229 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-229 0   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2008-06-06   
312-229 1   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2000-03-10   
312-229 2   9329 AMERITECH ILLINOIS 358      
312-229 3   9329 AMERITECH ILLINOIS 358      
312-229 4   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2000-03-10   
312-229 5   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2000-03-10   
312-229 6   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2000-03-10   
312-229 7   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2000-03-10   
312-229 8   9329 AMERITECH ILLINOIS 358      
312-229 9   4717 PAETEC COMMUNICATIONS, INC. - IL 358   2008-07-02   
312-245 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-276 A CHCHILLEDS0  8950 ALLEGIANCE TELECOM, INC. - IL 358      
312-321 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-329 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-379 A CHCGILWUDS0  7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358      
312-379 0   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358      
312-379 1   9329 AMERITECH ILLINOIS 358   2002-06-03   
312-379 2   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-379 3   4604 FIRST COMMUNICATIONS LLC - IL 358   2005-02-24   
312-379 4   9329 AMERITECH ILLINOIS 358   2000-05-05   
312-379 5   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358      
312-379 6   9329 AMERITECH ILLINOIS 358   2000-05-05   
312-379 7   9329 AMERITECH ILLINOIS 358   2000-05-05   
312-379 8   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-379 9   984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-02-25   
312-396 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-410 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-464 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-467 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-494 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-527 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-595 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      
312-644 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-645 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-661 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-661 0   9329 AMERITECH ILLINOIS 358      
312-661 1   9329 AMERITECH ILLINOIS 358      
312-661 2   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2013-02-08   
312-661 3   9329 AMERITECH ILLINOIS 358      
312-661 4   9329 AMERITECH ILLINOIS 358      
312-661 5   984E BANDWIDTH.COM CLEC, LLC - IL 358   2014-05-24   
312-661 6   6664 SPRINT SPECTRUM L.P. 358   2011-05-26   
312-661 7   9329 AMERITECH ILLINOIS 358      
312-661 8   9329 AMERITECH ILLINOIS 358      
312-661 9   9329 AMERITECH ILLINOIS 358      
312-670 A CHCGILIDDS2  9329 AMERITECH ILLINOIS 358      
312-742 A CHCGILIDDS0  9329 AMERITECH ILLINOIS 358      

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

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