Local Calling Guide

Area code/prefix search

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

NXX: 475

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-475 A Chelsea MA BSTPMALLDS3  892D ONVOY, LLC - MA 128      
857-475 0 Chelsea MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2021-11-27   
857-475 1 Chelsea MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2021-11-27   
857-475 3 Chelsea MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-475 4 Chelsea MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-475 5 Chelsea MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2024-12-06   
857-475 7 Chelsea MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2021-06-03   
857-475 8 Chelsea MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2024-03-07   
857-475 9 Chelsea MA BSTPMALLDS3  892D ONVOY, LLC - MA 128   2024-03-07   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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