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: 349

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-349 A Winthrop MA BSTNMABLOMD  990E BANDWIDTH.COM CLEC, LLC - MA 128      
857-349 0 Winthrop MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2018-11-22   
857-349 1 Winthrop MA   268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2019-03-06   
857-349 2 Winthrop MA   892D ONVOY, LLC - MA 128   2021-04-06   
857-349 4 Winthrop MA   892D ONVOY, LLC - MA 128   2021-03-07   
857-349 5 Winthrop MA   892D ONVOY, LLC - MA 128   2021-03-07   
857-349 6 Winthrop MA   318J COMCAST IP PHONE, LLC 128   2019-05-10   
857-349 7 Winthrop MA   624H ONVOY SPECTRUM, LLC 128   2021-04-15   
857-349 8 Winthrop MA   073H TELNYX LLC 128   2019-04-29   
857-349 9 Winthrop MA   892D ONVOY, LLC - MA 128   2020-07-07   

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

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