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: 691

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-691 A Anaconda MT MSSLMTAG5MD  6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-691 0 Anaconda MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648      
406-691 4 Anaconda MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2019-08-09   
406-691 7 Anaconda MT   508J CENTURYLINK COMMUNICATIONS, LLC 648   2014-05-24   
406-691 8 Anaconda MT   624H ONVOY SPECTRUM, LLC 648   2021-07-18   
406-691 9 Anaconda MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2015-08-10   

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

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