Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 757

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-757 A Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358      
312-757 0 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2013-11-14   
312-757 1 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2013-06-23   
312-757 2 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2013-06-23   
312-757 3 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2023-09-15   
312-757 4 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2013-06-23   
312-757 5 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2013-06-23   
312-757 6 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2013-06-23   
312-757 7 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-08-15   
312-757 8 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-08-15   
312-757 9 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2013-11-14   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.