Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 605 [Rate centres in NPA 605] [Dial plan for NPA 605]

NXX: 381

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-381 A Rapid City SD RPCYSDCO5MD  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640      

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

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