Local Calling Guide

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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-440 A Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-440 0 Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-440 1 Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-440 2 Helena MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2025-09-14   
406-440 3 Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-440 4 Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-440 5 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648   2024-02-22   
406-440 6 Helena MT HLNAMTMAWMD  6529 T-MOBILE USA, INC. 648   2024-02-22   
406-440 7 Helena MT   520K TDS METROCOM, LLC 648   2025-11-17   
406-440 8 Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-440 9 Helena MT HLNAMTHODS1  3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

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