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: 379

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-379 A Roxbury MA SOVLMAAB6MD  939H COMMIO, LLC 128   2024-12-28   
857-379 0 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2022-08-25   
857-379 1 Roxbury MA   939H COMMIO, LLC 128   2021-10-11   
857-379 2 Roxbury MA   939H COMMIO, LLC 128   2021-10-11   
857-379 3 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2021-10-18   
857-379 4 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2022-02-07   
857-379 5 Roxbury MA   624H ONVOY SPECTRUM, LLC 128   2021-11-21   
857-379 6 Roxbury MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2022-02-07   
857-379 7 Roxbury MA   624H ONVOY SPECTRUM, LLC 128   2021-11-21   
857-379 8 Roxbury MA   939H COMMIO, LLC 128   2021-10-11   
857-379 9 Roxbury MA   939H COMMIO, LLC 128   2021-10-11   

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

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