Local Calling Guide

Area code/prefix search

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

NXX: 392

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-392 A Jamaica Plain MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-392 0 Jamaica Plain MA   624H ONVOY SPECTRUM, LLC 128   2022-03-21   
857-392 1 Jamaica Plain MA   624H ONVOY SPECTRUM, LLC 128   2022-03-21   
857-392 2 Jamaica Plain MA   892D ONVOY, LLC - MA 128   2021-08-14   
857-392 3 Jamaica Plain MA   892D ONVOY, LLC - MA 128   2021-08-14   
857-392 4 Jamaica Plain MA   892D ONVOY, LLC - MA 128   2021-08-14   
857-392 5 Jamaica Plain MA   892D ONVOY, LLC - MA 128   2021-08-14   
857-392 6 Jamaica Plain MA   892D ONVOY, LLC - MA 128   2022-12-16   
857-392 7 Jamaica Plain MA   624H ONVOY SPECTRUM, LLC 128   2021-11-19   
857-392 8 Jamaica Plain MA   624H ONVOY SPECTRUM, LLC 128   2021-11-19   
857-392 9 Jamaica Plain MA   892D ONVOY, LLC - MA 128   2022-12-16   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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