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: 947

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-947 A Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-947 0 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 1 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 2 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 3 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 4 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 5 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 6 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 7 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 8 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   
312-947 9 Chicago Zone 01-Calumet IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358   2010-12-18   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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