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: 617

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-617 A Hill City SD   6701 AERIAL COMMUNICATIONS, INC. 640   2026-10-01   
605-617 7 Hill City SD   6701 AERIAL COMMUNICATIONS, INC. 640   2026-10-01   
605-617 8 Hill City SD   6701 AERIAL COMMUNICATIONS, INC. 640   2026-10-01   
605-617 9 Hill City SD   6701 AERIAL COMMUNICATIONS, INC. 640   2026-10-01   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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