Local Calling Guide

Area code/prefix search

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

NXX: 561

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-561 A Chicago Zone 01-Calumet IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358      
312-561 0 Chicago Zone 01-Calumet IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2012-08-17   
312-561 1 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2013-05-02   
312-561 2 Chicago Zone 01-Calumet IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358   2014-01-21   
312-561 3 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-05-02   
312-561 4 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-05-02   
312-561 5 Chicago Zone 01-Calumet IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358   2013-05-11   
312-561 6 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2014-02-06   
312-561 7 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2012-08-30   
312-561 8 Chicago Zone 01-Calumet IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2012-08-30   
312-561 9 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2012-09-11   

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

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