Local Calling Guide

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Castlewood, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-414 A CLLKSDXA0MD  920F MCC TELEPHONY OF THE MID-WEST, LLC - SD 640      
605-414 1 CLLKSDXA0MD  920F MCC TELEPHONY OF THE MID-WEST, LLC - SD 640   2010-09-26   
605-414 4   145J TERRA NOVA TELECOM INC. 640   2025-08-01   
605-793 A CLLKSDXADS0  1651 INTERSTATE TELECOM COOP, INC. - SD 640      
605-804 A SXFLSDCOX9X  6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      

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

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