Local Calling Guide

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Mound City, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-955 A HRRDSDXADS1  1685 VALLEY TELECOM COOP. ASSN., INC. 640      

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

Sponsored by: ISP Telecom

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