Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

OCN: 693G TELEPORT COMMUNICATIONS AMERICA SD-LLC

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
605-269 6 Spearfish SD   640   2012-09-05   
605-308 5 North Sioux City SD   630   2022-09-02   
605-450 3 Redfield SD   640   2015-11-27   
605-461 5 Huron SD   640   2012-10-15   
605-499 3 Sturgis SD   640   2020-08-26   
605-510 3 Rapid City SD   640   2025-10-27   
605-550 6 Mitchell SD   640   2016-03-21   
605-622 1 Aberdeen SD   640   2016-03-09   
605-646 6 Rapid City SD   640   2012-08-01   
605-653 7 Yankton SD   640   2018-10-08   
605-699 2 Belle Fourche SD   640   2020-08-18   
605-730 7 Chamberlain SD   640   2017-03-10   
605-741 6 Vermillion SD   640   2018-04-02   
605-776 6 Pierre SD   640   2014-03-03   
605-777 6 Harrisburg-Tea SD   640   2018-04-09   
605-906 A Sioux Falls SD SXFLSDCOXMD  640      
605-906 6 Sioux Falls SD   640   2012-03-29   
605-910 6 Sioux Falls SD   640   2021-12-03   
605-924 5 Milbank SD   640   2020-08-26   
605-954 6 Watertown SD   640   2017-09-01   
605-974 6 Rapid City SD   640   2025-06-19   
605-974 7 Rapid City SD   640   2025-06-19   

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

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