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: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-307 A Hill City SD SXFLSDPSDS1  580H AIRUS, INC. - SD 640      
605-307 0 Hill City SD   6701 AERIAL COMMUNICATIONS, INC. 640   2025-03-27   
605-307 1 Hill City SD   580H AIRUS, INC. - SD 640   2019-06-16   
605-307 2 Hill City SD   5180 LEVEL 3 COMMUNICATIONS, LLC - SD 640   2020-11-13   
605-307 3 Hill City SD   162G ONVOY, LLC - SD 640   2020-08-21   
605-307 4 Hill City SD   073H TELNYX LLC 640   2019-09-29   
605-307 5 Hill City SD   162G ONVOY, LLC - SD 640   2020-08-21   
605-307 6 Hill City SD   162G ONVOY, LLC - SD 640   2020-10-23   
605-307 7 Hill City SD   162G ONVOY, LLC - SD 640   2020-12-07   
605-307 8 Hill City SD   162G ONVOY, LLC - SD 640   2021-02-12   
605-307 9 Hill City SD   162G ONVOY, LLC - SD 640   2021-02-12   

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

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