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: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-320 A Brookings SD   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2025-10-03   
605-320 9 Brookings SD   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2025-10-03   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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