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: 540

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-540 A North Sioux City SD SXCYIA78X1X  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 630      
605-540 0 North Sioux City SD SXCYIA78X1X  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 630      
605-540 1 North Sioux City SD SXCYIADT9MD  162G ONVOY, LLC - SD 630   2018-10-19   
605-540 2 North Sioux City SD SXCYIA78X1X  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 630   2016-02-28   
605-540 3 North Sioux City SD SXCYIADTQMD  508J CENTURYLINK COMMUNICATIONS, LLC 630   2016-12-29   
605-540 4 North Sioux City SD SXCYIA78X1X  5180 LEVEL 3 COMMUNICATIONS, LLC - SD 630      
605-540 5 North Sioux City SD SXCYIADTXDX  829J PAETEC ITEL, LLC 630   2010-10-28   
605-540 6 North Sioux City SD   145J TERRA NOVA TELECOM INC. 630   2025-04-10   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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