Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-355 A HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      

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

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