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: 432

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-432 A Brookline MA NRTNMAAACM4  6889 OMNIPOINT MIAMI E LICENSE, LLC 128   2026-01-19  2026-09-05 

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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