Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-604 A Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 0 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 1 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 2 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 3 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 4 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358   2004-11-27   
312-604 5 Chicago Zone 01-Canal IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2019-03-04   
312-604 6 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2002-10-16   
312-604 7 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 8 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      
312-604 9 Chicago Zone 01-Canal IL CHCGILTCDS0  7056 XO ILLINOIS, INC. 358      

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

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