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: 299

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-299 A Belmont MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-299 0 Belmont MA   892D ONVOY, LLC - MA 128   2019-01-05   
857-299 1 Belmont MA   892D ONVOY, LLC - MA 128   2018-03-03   
857-299 2 Belmont MA   892D ONVOY, LLC - MA 128   2019-02-23   
857-299 3 Belmont MA   892D ONVOY, LLC - MA 128   2019-02-23   
857-299 4 Belmont MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2019-03-07   
857-299 5 Belmont MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2019-03-07   
857-299 6 Belmont MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2019-03-07   
857-299 7 Belmont MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2019-03-07   
857-299 8 Belmont MA   892D ONVOY, LLC - MA 128   2019-01-05   
857-299 9 Belmont MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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