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:

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-445 A Chicago Zone 01-Superior IL CHCGILSUDS2  9329 AMERITECH ILLINOIS 358      
312-445 0 Chicago Zone 01-Superior IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2007-10-09   
312-445 1 Chicago Zone 01-Superior IL   5562 METRO PCS, INC. 358   2016-02-15   
312-445 2 Chicago Zone 01-Superior IL   7056 XO ILLINOIS, INC. 358   2008-04-17   
312-445 3 Chicago Zone 01-Superior IL   7056 XO ILLINOIS, INC. 358   2008-04-16   
312-445 4 Chicago Zone 01-Superior IL   5447 ACCESS ONE, INC. - IL 358   2008-04-17   
312-445 5 Chicago Zone 01-Superior IL   5447 ACCESS ONE, INC. - IL 358   2008-04-17   
312-445 6 Chicago Zone 01-Superior IL   7721 BROADWING COMMUNICATIONS, LLC - IL 358   2008-05-13   
312-445 7 Chicago Zone 01-Superior IL   7721 BROADWING COMMUNICATIONS, LLC - IL 358   2008-05-13   
312-445 8 Chicago Zone 01-Superior IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2008-05-14   
312-445 9 Chicago Zone 01-Superior IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2007-10-26   

Last updated: Tue, 31 Dec 2019 02:37:20 UTC

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