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: 429

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-429 A Winnett MT RNDPMTXCDS0  2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 0 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 1 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 2 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 4 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 5 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 6 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 7 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 8 Winnett MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2026-06-15   
406-429 9 Winnett MT   2246 MID-RIVERS TEL. COOP., INC. 650      

Last updated: Sat, 02 May 2026 12:20:53 UTC

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