Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 617 [Rate centres in NPA 617] [Dial plan for NPA 617]

NXX: 403

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-403 A Brighton MA BSTNMABLOMD  9748 AMERICAN MESSAGING SERVICES, LLC 128      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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