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: 603

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-603 A Rapid City SD   106F BANDWIDTH.COM CLEC, LLC - SD 640   2026-07-04   
605-603 0 Rapid City SD   106F BANDWIDTH.COM CLEC, LLC - SD 640   2026-07-04   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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