Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: HAVRMTXCDS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-292 A Joplin MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-352 A Box Elder MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-355 A Rudyard MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-357 A Chinook MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-372 A Kremlin MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-376 A Gildford MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 A Big Sandy MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-379 A Turner MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-386 A Hopp-Illiad MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-394 A North Havre MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-395 A South Havre MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-397 A Hingham MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-398 A North Havre MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-456 A South Chester MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-462 A Winifred MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-658 A South Malta MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-674 A Whitewater MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-739 A Loma MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-759 A Chester MT 2257 TRIANGLE TEL. COOP. ASSN., INC. 648      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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