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: 523

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-523 A Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 0 Chicago Zone 01-Calumet IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2005-06-24   
312-523 1 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2010-11-05   
312-523 2 Chicago Zone 01-Calumet IL CHCGILWBXWZ  829J PAETEC ITEL, LLC 358   2005-06-24   
312-523 3 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 4 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 5 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 6 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 7 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 8 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      
312-523 9 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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