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: 837

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-837 A Charlestown MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-837 0 Charlestown MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2021-01-09   
857-837 1 Charlestown MA   892D ONVOY, LLC - MA 128   2020-07-26   
857-837 2 Charlestown MA   892D ONVOY, LLC - MA 128   2020-07-26   
857-837 3 Charlestown MA   892D ONVOY, LLC - MA 128   2020-07-26   
857-837 4 Charlestown MA   624H ONVOY SPECTRUM, LLC 128   2021-04-08   
857-837 5 Charlestown MA   892D ONVOY, LLC - MA 128   2022-11-24   
857-837 6 Charlestown MA   892D ONVOY, LLC - MA 128   2021-03-07   
857-837 7 Charlestown MA   892D ONVOY, LLC - MA 128   2021-03-07   
857-837 9 Charlestown MA   073H TELNYX LLC 128   2021-03-04   

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

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