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: 221

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-221 A Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358      
312-221 0 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 1 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 2 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 3 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2011-08-08   
312-221 4 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 5 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 6 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 7 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   
312-221 8 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-09   
312-221 9 Chicago Zone 01-Calumet IL CHCGILMF5MD  6529 T-MOBILE USA, INC. 358   2011-08-08   

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

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