Local Calling Guide

Area code/prefix search

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Highmore, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-478 A SXFLSDCONMD  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640      
605-478 0   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2005-06-14   
605-478 1   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2010-11-15   
605-478 7   516J TON80 COMMUNICATIONS, LLC 640   2022-04-21   
605-852 A HGHMSDXADS1  1680 VENTURE COMMUNICATIONS COOPERATIVE 640      
605-870 A SXFLSDCOX9X  6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-870 0   6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-870 1   6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-870 2   6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-870 3   145J TERRA NOVA TELECOM INC. 640   2025-08-01   
605-870 9   6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-871 A SXFLSDCOX9X  6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-871 0   6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      
605-871 9   6569 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - SD 640      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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