Local Calling Guide

Area code/prefix search

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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 497

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-497 A Charlestown MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      
857-497 0 Charlestown MA   892D ONVOY, LLC - MA 128   2024-03-07   
857-497 1 Charlestown MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2024-09-22   
857-497 2 Charlestown MA   6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2024-09-22   
857-497 5 Charlestown MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-497 6 Charlestown MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-497 7 Charlestown MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-497 9 Charlestown MA   5562 METROPCS, INC. 128   2023-10-20   

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

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