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: 380

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-380 A East Boston MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-380 0 East Boston MA   892D ONVOY, LLC - MA 128   2021-04-06   
857-380 1 East Boston MA   892D ONVOY, LLC - MA 128   2020-07-12   
857-380 2 East Boston MA   892D ONVOY, LLC - MA 128   2020-07-12   
857-380 3 East Boston MA   624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-380 4 East Boston MA   624H ONVOY SPECTRUM, LLC 128   2021-04-08   
857-380 5 East Boston MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-380 6 East Boston MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-380 7 East Boston MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-380 8 East Boston MA   892D ONVOY, LLC - MA 128   2021-03-06   
857-380 9 East Boston MA   892D ONVOY, LLC - MA 128   2021-04-06   

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

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