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: 651

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-651 A Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-651 0 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-651 1 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-651 2 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-651 3 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2019-12-30   
312-651 4 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2008-06-09   
312-651 5 Chicago Zone 01-Canal IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS LLC - IL 358   2006-06-22   
312-651 6 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2008-06-09   
312-651 7 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-651 8 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      
312-651 9 Chicago Zone 01-Canal IL CHCGILCLDS3  9329 ILLINOIS BELL TEL CO 358      

Last updated: Fri, 13 May 2022 22:16:13 UTC

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