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: 550

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-550 A Mitchell SD SXFLSDCORMD  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 640      
605-550 0 Mitchell SD   106F BANDWIDTH.COM CLEC, LLC - SD 640   2008-11-29   
605-550 1 Mitchell SD   106F BANDWIDTH.COM CLEC, LLC - SD 640   2016-09-15   
605-550 2 Mitchell SD   106F BANDWIDTH.COM CLEC, LLC - SD 640   2021-01-10   
605-550 3 Mitchell SD   580H AIRUS, INC. - SD 640   2020-07-23   
605-550 4 Mitchell SD   5180 LEVEL 3 COMMUNICATIONS, LLC - SD 640   2005-04-09   
605-550 5 Mitchell SD   145J TERRA NOVA TELECOM INC. 640   2024-02-15   
605-550 6 Mitchell SD   693G TELEPORT COMMUNICATIONS AMERICA SD-LLC 640   2016-03-21   
605-550 7 Mitchell SD   162G ONVOY, LLC - SD 640   2013-12-16   
605-550 8 Mitchell SD   162G ONVOY, LLC - SD 640   2013-12-16   
605-550 9 Mitchell SD   073H TELNYX LLC 640   2017-03-31   

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

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