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: 833

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-833 A Winthrop MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-833 7 Winthrop MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-833 8 Winthrop MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   
857-833 9 Winthrop MA CMBRMABENMD  624H ONVOY SPECTRUM, LLC 128   2025-01-03   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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