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: 973

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-973 A Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-973 0 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-15   
312-973 1 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2014-05-24   
312-973 2 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-15   
312-973 3 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2014-04-12   
312-973 4 Chicago Zone 01-Calumet IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2014-04-12   
312-973 5 Chicago Zone 01-Calumet IL CHCGILCPDS9  138G LEVEL 3 TELECOM OF ILLINOIS, LLC - IL 358   2014-04-15   
312-973 6 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-15   
312-973 7 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-15   
312-973 8 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-15   
312-973 9 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2014-04-15   

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

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