Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 508 [Rate centres in NPA 508] [Dial plan for NPA 508]

NXX: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-320 A Grafton MA CATNMAAKAMD  6387 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MA 128      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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