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: 528

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-528 A Chicago Zone 01-Calumet IL CHCGILCADS0  9329 ILLINOIS BELL TEL CO 358      
312-528 0 Chicago Zone 01-Calumet IL CHCGILCADS0  9329 ILLINOIS BELL TEL CO 358      
312-528 1 Chicago Zone 01-Calumet IL CHCGILCADS0  9329 ILLINOIS BELL TEL CO 358      
312-528 2 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   1999-11-30   
312-528 3 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2001-02-27   
312-528 4 Chicago Zone 01-Calumet IL CHCGILCADS0  9329 ILLINOIS BELL TEL CO 358      
312-528 5 Chicago Zone 01-Calumet IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2019-12-26   
312-528 6 Chicago Zone 01-Calumet IL CHCGILCADS0  9329 ILLINOIS BELL TEL CO 358      
312-528 7 Chicago Zone 01-Calumet IL CHCGILTCDS4  7056 XO ILLINOIS, INC. 358   2011-01-05   
312-528 8 Chicago Zone 01-Calumet IL CHCGILCADS0  9329 ILLINOIS BELL TEL CO 358      
312-528 9 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2000-08-29   

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

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