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: 957

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-957 A Terry MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-957 0 Terry MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-957 1 Terry MT   588H AIRUS, INC. - MT 650   2020-03-01   
406-957 2 Terry MT   453F ONVOY, LLC - MT 650   2021-03-07   
406-957 3 Terry MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2023-02-27   
406-957 6 Terry MT   453F ONVOY, LLC - MT 650   2019-09-15   
406-957 7 Terry MT   453F ONVOY, LLC - MT 650   2019-09-15   
406-957 8 Terry MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-957 9 Terry MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      

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

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