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: 204

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-204 A Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 0 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 1 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 2 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 3 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 4 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 5 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-204 6 Chicago Zone 01-Superior IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-204 7 Chicago Zone 01-Superior IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-204 8 Chicago Zone 01-Superior IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-204 9 Chicago Zone 01-Superior IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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