Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Chester, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-759 A HAVRMTXCDS0  2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-759 2   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2019-11-25   
406-759 5   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-759 6   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-759 8   2257 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-759 9   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2020-02-24   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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