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: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-557 A Clearfield SD WNNRSDXADS1  1686 VIVIAN TEL CO DBA GOLDEN WEST TELECOMMUNICATIONS 640      

Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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