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: 434

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-434 A Milbank SD NWEFSDXADS1  683C RC COMMUNICATIONS, INC. - SD 640      

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

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