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
312-957 A Chicago Zone 01-Wabash IL CHCGILWBDS2  9329 AMERITECH ILLINOIS 358      
312-957 0 Chicago Zone 01-Wabash IL   9329 AMERITECH ILLINOIS 358      
312-957 1 Chicago Zone 01-Wabash IL   9329 AMERITECH ILLINOIS 358      
312-957 2 Chicago Zone 01-Wabash IL   9329 AMERITECH ILLINOIS 358      
312-957 3 Chicago Zone 01-Wabash IL   9329 AMERITECH ILLINOIS 358      
312-957 4 Chicago Zone 01-Wabash IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-07-03   
312-957 5 Chicago Zone 01-Wabash IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-07-03   
312-957 6 Chicago Zone 01-Wabash IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-07-03   
312-957 7 Chicago Zone 01-Wabash IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-07-03   
312-957 8 Chicago Zone 01-Wabash IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-07-03   
312-957 9 Chicago Zone 01-Wabash IL   9329 AMERITECH ILLINOIS 358      

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

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