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: 673

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-673 A Hays MT HAYSMTXCRS1  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 0 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 1 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 2 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 3 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 4 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 5 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 6 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 7 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 8 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-673 9 Hays MT   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      

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

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