Local Calling Guide

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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-399 A Roxbury MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128      
857-399 0 Roxbury MA   990E BANDWIDTH.COM CLEC, LLC - MA 128      
857-399 2 Roxbury MA   990E BANDWIDTH.COM CLEC, LLC - MA 128      
857-399 3 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2008-07-17   
857-399 4 Roxbury MA   515J IP HORIZON LLC 128      
857-399 5 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2008-07-17   
857-399 6 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2008-07-24   
857-399 7 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2008-07-24   
857-399 8 Roxbury MA   892D ONVOY, LLC - MA 128   2010-03-15   
857-399 9 Roxbury MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2011-06-03   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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