Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 304 [Rate centres in NPA 304] [Dial plan for NPA 304]

NXX: 597

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
304-597 A Keyser WV   449F ONVOY, LLC - WV 240      
304-597 0 Keyser WV   145J TERRA NOVA TELECOM INC. 240   2026-06-03   
304-597 3 Keyser WV   449F ONVOY, LLC - WV 240      

Last updated: Sun, 17 May 2026 03:26:51 UTC

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