Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 800

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-800 A Boston MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-800 0 Boston MA   892D ONVOY, LLC - MA 128   2015-05-22   
857-800 1 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2015-07-23   
857-800 2 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2015-07-23   
857-800 3 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2015-07-23   
857-800 4 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2015-07-23   
857-800 5 Boston MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2015-07-23   
857-800 6 Boston MA   5562 METROPCS, INC. 128   2016-06-19   
857-800 7 Boston MA   5562 METROPCS, INC. 128   2016-06-19   
857-800 8 Boston MA   892D ONVOY, LLC - MA 128   2015-05-22   
857-800 9 Boston MA   892D ONVOY, LLC - MA 128   2015-05-22   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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