Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-432 A SNBRMTXCDS0  2248 NORTHERN TEL. COOP., INC. 648      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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