Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 971 [Rate centres in NPA 971] [Dial plan for NPA 971]

NXX: 538

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
971-538 A Silverton OR   750E ONVOY, LLC - OR 672   2026-08-29   
971-538 0 Silverton OR   750E ONVOY, LLC - OR 672   2026-08-29   

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

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