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: 285

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-285 A Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 0 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2006-12-09   
312-285 1 Chicago Zone 01-Calumet IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2010-10-02   
312-285 2 Chicago Zone 01-Calumet IL CHCGILCLXOX  516C AT&T CORP. 358   2005-05-09   
312-285 3 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 4 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 5 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 6 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 7 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 8 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-285 9 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      

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

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