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      

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

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