Local Calling Guide

Area code/prefix search

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OCN: 2257 TRIANGLE TEL. COOP. ASSN., INC.

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
406-292 A Joplin MT HAVRMTXCDS0  648      
406-292 1 Joplin MT   648      
406-292 3 Joplin MT   648      
406-292 4 Joplin MT   648      
406-292 7 Joplin MT   648      
406-292 9 Joplin MT   648      
406-326 A Reedpoint MT BGTMMTXCDS0  650      
406-352 A Box Elder MT HAVRMTXCDS0  648      
406-355 A Rudyard MT HAVRMTXCDS0  648      
406-357 A Chinook MT HAVRMTXCDS0  648      
406-357 0 Chinook MT   648      
406-357 2 Chinook MT   648      
406-357 3 Chinook MT   648      
406-357 4 Chinook MT   648      
406-357 8 Chinook MT   648      
406-372 A Kremlin MT HAVRMTXCDS0  648      
406-376 A Gildford MT HAVRMTXCDS0  648      
406-378 A Big Sandy MT HAVRMTXCDS0  648      
406-378 0 Big Sandy MT   648      
406-378 1 Big Sandy MT   648      
406-378 2 Big Sandy MT   648      
406-378 3 Big Sandy MT   648      
406-378 4 Big Sandy MT   648      
406-378 5 Big Sandy MT   648      
406-378 6 Big Sandy MT   648      
406-378 7 Big Sandy MT   648      
406-378 9 Big Sandy MT   648      
406-379 A Turner MT HAVRMTXCDS0  648      
406-386 A Hopp-Illiad MT HAVRMTXCDS0  648      
406-394 A North Havre MT HAVRMTXCDS0  648      
406-394 0 North Havre MT   648      
406-394 1 North Havre MT   648      
406-394 2 North Havre MT   648      
406-394 3 North Havre MT   648      
406-394 4 North Havre MT   648      
406-394 5 North Havre MT   648      
406-394 7 North Havre MT   648      
406-394 8 North Havre MT   648      
406-394 9 North Havre MT   648      
406-395 A South Havre MT HAVRMTXCDS0  648      
406-395 1 South Havre MT   648   2016-08-15   
406-395 4 South Havre MT   648      
406-395 5 South Havre MT   648      
406-395 6 South Havre MT   648      
406-395 8 South Havre MT   648      
406-397 A Hingham MT HAVRMTXCDS0  648      
406-398 A North Havre MT HAVRMTXCDS0  648      
406-398 1 North Havre MT   648      
406-398 5 North Havre MT   648      
406-398 9 North Havre MT   648      
406-456 A South Chester MT HAVRMTXCDS0  648      
406-462 A Winifred MT HAVRMTXCDS0  648      
406-537 A Melville MT BGTMMTXCDS0  650      
406-658 A South Malta MT HAVRMTXCDS0  648      
406-663 A Rapelje MT BGTMMTXCDS0  650      
406-667 A Broadview MT BGTMMTXCDS0  650      
406-669 A Molt MT BGTMMTXCDS0  650      
406-673 A Hays MT HAYSMTXCRS1  648      
406-673 0 Hays MT   648      
406-673 1 Hays MT   648      
406-673 2 Hays MT   648      
406-673 3 Hays MT   648      
406-673 4 Hays MT   648      
406-673 5 Hays MT   648      
406-673 6 Hays MT   648      
406-673 7 Hays MT   648      
406-673 8 Hays MT   648      
406-673 9 Hays MT   648      
406-674 A Whitewater MT HAVRMTXCDS0  648      
406-674 0 Whitewater MT   648      
406-674 1 Whitewater MT   648      
406-674 2 Whitewater MT   648      
406-674 3 Whitewater MT   648      
406-674 4 Whitewater MT   648      
406-674 5 Whitewater MT   648      
406-674 6 Whitewater MT   648      
406-674 7 Whitewater MT   648      
406-674 8 Whitewater MT   648      
406-674 9 Whitewater MT   648      
406-739 A Loma MT HAVRMTXCDS0  648      
406-759 A Chester MT HAVRMTXCDS0  648      
406-759 5 Chester MT   648      
406-759 6 Chester MT   648      
406-759 8 Chester MT   648      
406-932 A Big Timber MT BGTMMTXCDS0  650      
406-932 0 Big Timber MT   650      
406-932 2 Big Timber MT   650      
406-932 3 Big Timber MT   650      
406-932 4 Big Timber MT   650      
406-932 5 Big Timber MT   650      
406-932 6 Big Timber MT   650      
406-932 8 Big Timber MT   650      

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

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