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
312-255 A Chicago Zone 01-Superior IL CHCGILSUDS2  9329 AMERITECH ILLINOIS 358      
312-255 0 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 1 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 2 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 3 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 4 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 5 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 6 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 7 Chicago Zone 01-Superior IL   516C AT&T CORP. 358      
312-255 8 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      
312-255 9 Chicago Zone 01-Superior IL   9329 AMERITECH ILLINOIS 358      

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

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