Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 660

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-660 A Dillon MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-660 0 Dillon MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-660 1 Dillon MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-660 2 Dillon MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-660 3 Dillon MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-660 4 Dillon MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-660 5 Dillon MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-660 6 Dillon MT   453F ONVOY, LLC - MT 648   2012-12-13   
406-660 7 Dillon MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2014-07-17   
406-660 8 Dillon MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2024-11-10   

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

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