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   

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

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