Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 605 [Rate centres in NPA 605] [Dial plan for NPA 605]

NXX: 504

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-504 A Sioux Falls SD SXFLSDCODS2  9631 QWEST CORPORATION 640      
605-504 0 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 1 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 2 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 3 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 4 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 5 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 6 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 7 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 8 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   
605-504 9 Sioux Falls SD   9631 QWEST CORPORATION 640   2016-10-15   

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

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