Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: JFSNSDXARS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
605-966 A Jefferson SD 1666 JEFFERSON TEL. CO. 640      

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

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