Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-644 A CHRLMTXCRS1  2235 BLACKFOOT TEL. COOP., INC. 648      
406-644 1 CHRLMT010MD  986F WESTERN MONTANA COMMUNITYTEL INC. - MT 648   2013-08-25   
406-644 2 CHRLMTXCRS1  2235 BLACKFOOT TEL. COOP., INC. 648      
406-644 3 CHRLMTXCRS1  2235 BLACKFOOT TEL. COOP., INC. 648      
406-644 4   145J TERRA NOVA TELECOM INC. 648   2025-10-09   
406-644 9 CHRLMTXCRS1  2235 BLACKFOOT TEL. COOP., INC. 648      

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

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