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: 545

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-545 A Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 0 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2007-09-07   
312-545 1 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 2 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2007-09-07   
312-545 3 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 4 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 5 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 6 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 7 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 8 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358      
312-545 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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