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: 578

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
508-578 A Dover MA   990E BANDWIDTH.COM CLEC, LLC - MA 128      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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