Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 842

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-842 A Sheridan MT FRFDMTXCDS1  2255 3 RIVERS TEL. COOP., INC. 648      
406-842 1 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 2 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 3 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 4 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 5 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 6 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 7 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 8 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      
406-842 9 Sheridan MT   2255 3 RIVERS TEL. COOP., INC. 648      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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