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: 341

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-341 A Belmont MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128      
857-341 0 Belmont MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2019-04-11   
857-341 1 Belmont MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2019-04-11   
857-341 2 Belmont MA   597F VOIP INNOVATIONS, LLC 128   2019-07-22   
857-341 3 Belmont MA   892D ONVOY, LLC - MA 128   2020-06-12   
857-341 4 Belmont MA   892D ONVOY, LLC - MA 128   2020-06-12   
857-341 5 Belmont MA   624H ONVOY SPECTRUM, LLC 128   2021-04-05   
857-341 6 Belmont MA   892D ONVOY, LLC - MA 128   2021-04-06   
857-341 7 Belmont MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-341 8 Belmont MA   892D ONVOY, LLC - MA 128   2021-03-07   
857-341 9 Belmont MA   892D ONVOY, LLC - MA 128   2021-03-07   

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

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