Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-330 A MSSLMTEH4MD  792K CHARTER IP ENABLED SERVICES, LLC 648      
406-330 0   6529 T-MOBILE USA, INC. 648   2024-09-23   
406-330 2   792K CHARTER IP ENABLED SERVICES, LLC 648   2006-06-03   
406-330 3   145J TERRA NOVA TELECOM INC. 648   2025-10-06   
406-825 A CLTNMTXCRS1  2235 BLACKFOOT TEL. COOP., INC. 648      
406-825 3   2235 BLACKFOOT TEL. COOP., INC. 648      
406-825 9   2235 BLACKFOOT TEL. COOP., INC. 648      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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