Local Calling Guide

Area code/prefix search

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NPA: 304 [Rate centres in NPA 304] [Dial plan for NPA 304]

NXX: 631

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
304-631 A Clarksburg WV WLSMWV01CM8  6597 RAM TECHNOLOGIES, INC. - WV 256      

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

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