Local Calling Guide

Area code/prefix search

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Humboldt, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-363 A DLRPSDXADS1  1677 SIOUX VALLEY TEL DBA GOLDEN WEST TELECOMMUNICATION 640      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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