Local Calling Guide

Area code/prefix search

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Sioux Falls, SD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-988 5 SXFLSDCODS2  9631 QWEST CORPORATION 640      
605-988 6 SXFLSDCORMD  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 640   2014-10-24   
605-988 7 SXFLSDCONMD  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2009-11-08   
605-988 8 SXFLSDCORMD  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 640   2013-05-18   
605-988 9 SXFLSDCODS2  9631 QWEST CORPORATION 640      

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

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