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: 431

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-431 A Boston MA SOVLMAABHMD  700J WAVENATION, LLC 128   2025-09-06   
857-431 0 Boston MA SOVLMAABHMD  700J WAVENATION, LLC 128   2025-09-06   
857-431 1 Boston MA SOVLMAABDMD  490J BOOST SUBSCRIBERCO L.L.C. 128   2026-03-05   
857-431 2 Boston MA SOVLMAABDMD  490J BOOST SUBSCRIBERCO L.L.C. 128   2026-01-12   
857-431 3 Boston MA   116E INTRADO COMMUNICATIONS, LLC 128   2026-09-13   
857-431 4 Boston MA CMBRMABEQMD  321J HD CARRIER LLC 128   2026-05-09   
857-431 5 Boston MA   116E INTRADO COMMUNICATIONS, LLC 128   2026-09-13   
857-431 6 Boston MA   116E INTRADO COMMUNICATIONS, LLC 128   2026-09-13   
857-431 8 Boston MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2026-09-13   
857-431 9 Boston MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2026-09-13   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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