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: 631

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-631 A Chicago Zone 01-Calumet IL CHCGILDT8MD  508J CENTURYLINK COMMUNICATIONS, LLC 358      
312-631 0 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-05-24   
312-631 1 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2013-05-24   
312-631 2 Chicago Zone 01-Calumet IL CHCGILCLDS7  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2013-07-05   
312-631 3 Chicago Zone 01-Calumet IL CHCGILCLXOX  516C AT&T CORP. 358   2013-07-03   
312-631 4 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2013-05-01   
312-631 5 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2013-05-01   
312-631 6 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2013-05-01   
312-631 7 Chicago Zone 01-Calumet IL CHCGILDT8MD  508J CENTURYLINK COMMUNICATIONS, LLC 358   2013-05-31   
312-631 8 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2013-05-01   
312-631 9 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358   2013-05-01   

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

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