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: 837

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-837 A Chicago Zone 01-Calumet IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358      
312-837 0 Chicago Zone 01-Calumet IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2015-10-19   
312-837 1 Chicago Zone 01-Calumet IL CHCGILWUX1X  4717 PAETEC COMMUNICATIONS, INC. - IL 358   2015-11-04   
312-837 2 Chicago Zone 01-Calumet IL CHCGIL24DS3  4604 FIRST COMMUNICATIONS, LLC - IL 358   2016-06-17   
312-837 3 Chicago Zone 01-Calumet IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2015-10-18   
312-837 4 Chicago Zone 01-Calumet IL CHCGILWUX1X  4717 PAETEC COMMUNICATIONS, INC. - IL 358   2015-11-04   
312-837 5 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2015-10-26   
312-837 6 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2015-10-26   
312-837 7 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2015-10-26   
312-837 8 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2015-10-26   
312-837 9 Chicago Zone 01-Calumet IL BURGILAHGT3  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 358   2015-11-23   

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

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