Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: HRMSSDXARS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
605-255 A Hermosa SD 1660 FORT RANDALL TELCO DBA MT RUSHMORE TELEPHONE CO 640      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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