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: 227

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-227 A Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-227 0 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 1 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 2 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 3 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 4 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 5 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 6 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 7 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 8 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   
312-227 9 Chicago Zone 01-Calumet IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2010-10-15   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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