Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 617 [Rate centres in NPA 617] [Dial plan for NPA 617]

NXX: 370

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-370 A Chelsea MA CMBRMAMQDS0  4536 XO MASSACHUSETS, INC. 128      
617-370 0 Chelsea MA CMBRMAMQDS0  4536 XO MASSACHUSETS, INC. 128      
617-370 2 Chelsea MA CMBRMAWA0MD  3370 CTC COMMUNICATIONS CORP. - MA 128   2002-10-13   
617-370 3 Chelsea MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2006-01-27   
617-370 4 Chelsea MA CHTWMABMAMD  2899 BROADVIEW NETWORKS, INC. - MA 128   2004-02-23   
617-370 5 Chelsea MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128   2011-06-27   
617-370 6 Chelsea MA CMBRMAMQDS0  4536 XO MASSACHUSETS, INC. 128      
617-370 7 Chelsea MA SOVLMAAB2MD  966G LOCAL ACCESS LLC - MA 128   2013-04-08   
617-370 8 Chelsea MA SOVLMAABDS2  268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2011-07-11   
617-370 9 Chelsea MA BSTPMALL7MD  966G LOCAL ACCESS LLC - MA 128   2016-06-26   

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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