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: 693

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-693 A Warm Springs MT WRSPMTMARS1  9636 QWEST CORPORATION 648      
406-693 0 Warm Springs MT   453F ONVOY, LLC - MT 648   2021-03-07   
406-693 1 Warm Springs MT   453F ONVOY, LLC - MT 648   2007-03-19   
406-693 2 Warm Springs MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648      
406-693 3 Warm Springs MT   073H TELNYX LLC 648   2020-08-13   
406-693 4 Warm Springs MT   453F ONVOY, LLC - MT 648   2019-09-15   
406-693 5 Warm Springs MT   624H ONVOY SPECTRUM, LLC 648   2025-02-03   
406-693 6 Warm Springs MT   453F ONVOY, LLC - MT 648   2020-11-08   
406-693 7 Warm Springs MT   9636 QWEST CORPORATION 648      
406-693 8 Warm Springs MT   453F ONVOY, LLC - MT 648   2011-10-24   
406-693 9 Warm Springs MT   9636 QWEST CORPORATION 648      

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

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