Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Oelrichs, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-535 A HTSPSDXADS1  1659 GOLDEN WEST TEL COOP INC DBA GOLDEN WEST TELECOMM 640      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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