Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-674 A HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 0   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 1   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 2   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 3   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 4   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 5   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 6   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 7   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 8   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 9   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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