Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Jefferson, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-966 A JFSNSDXARS0  1666 JEFFERSON TEL. CO. 640      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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