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
312-821 A Chicago Zone 01-Superior IL EGVGILIFDS1  7196 MCI WORLDCOM COMMUNICATIONS, INC. - IL 358      
312-821 0 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 1 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 2 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 3 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 4 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 5 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 6 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 7 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 8 Chicago Zone 01-Superior IL   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-821 9 Chicago Zone 01-Superior IL   7196 MCI WORLDCOM COMMUNICATIONS, INC. - IL 358      

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

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