Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 458 [Rate centres in NPA 458] [Dial plan for NPA 458]

NXX: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
458-340 A Newport OR   750E ONVOY, LLC - OR 670   2026-08-29   
458-340 0 Newport OR   750E ONVOY, LLC - OR 670   2026-08-29   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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