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: 968

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-968 A Lewistown MT   321J HD CARRIER LLC 648      
406-968 0 Lewistown MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-968 4 Lewistown MT MSSLMTMA0MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-968 6 Lewistown MT MSSLMTMAYMD  771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 648   2019-05-03   
406-968 7 Lewistown MT   321J HD CARRIER LLC 648   2025-07-15   
406-968 8 Lewistown MT   321J HD CARRIER LLC 648   2025-07-15   
406-968 9 Lewistown MT   321J HD CARRIER LLC 648   2025-07-15   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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