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: 891

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-891 A Boston MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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