Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: SHLBMTALRL0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-424 A Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 1 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 2 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 4 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 5 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 7 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 8 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      
406-424 9 Shelby MT 3924 3 RIVERS TELEPHONE COOPERATIVE, INC. - MT 648      

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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