Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Custer, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-856 A RNDPMTXCDS0  2246 MID-RIVERS TEL. COOP., INC. 650      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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