Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Big Sandy, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-378 A HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 0 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 1 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 2 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 3 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 4 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 5 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 6 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 7 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-378 8 MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2024-10-17   
406-378 9 HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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