Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-466 A EGBTSDXA964  1647 CHEYENNE RIVER SIOUX TRIBAL TEL. AUTHORITY 640      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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