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: 610

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-610 A Missoula MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2025-03-03   
406-610 0 Missoula MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2025-03-04   
406-610 1 Missoula MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2025-03-04   
406-610 2 Missoula MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2025-03-04   
406-610 3 Missoula MT MSSLMTMACMD  6529 T-MOBILE USA, INC. 648   2025-06-20   
406-610 4 Missoula MT MSSLMTMACMD  6529 T-MOBILE USA, INC. 648   2025-07-11   
406-610 5 Missoula MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2026-04-12   
406-610 6 Missoula MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2025-08-29   
406-610 7 Missoula MT MSSLMTXC6MD  732J NUSO, LLC 648   2025-03-04   
406-610 8 Missoula MT GRFLMTMA7MD  453F ONVOY, LLC - MT 648   2025-03-04   
406-610 9 Missoula MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648   2025-03-03   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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