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
312-204 A Chicago Zone 01-Superior IL CHCGILSUDS2  9329 AMERITECH ILLINOIS 358      
312-204 0 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-204 1 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-204 2 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-204 3 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-204 4 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-204 5 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-204 6 Chicago Zone 01-Superior IL   7056 XO ILLINOIS, INC. 358   2008-10-31   
312-204 7 Chicago Zone 01-Superior IL   7056 XO ILLINOIS, INC. 358   2008-10-31   
312-204 8 Chicago Zone 01-Superior IL   7056 XO ILLINOIS, INC. 358   2008-10-31   
312-204 9 Chicago Zone 01-Superior IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2010-09-02   

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

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