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: 573

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-573 A Browning MT BRNGMTAQDS0  619J SIYEH COMMUNICATIONS 648      
406-573 0 Browning MT   619J SIYEH COMMUNICATIONS 648   2021-02-08   
406-573 1 Browning MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2015-06-30   
406-573 6 Browning MT   624H ONVOY SPECTRUM, LLC 648   2021-11-14   
406-573 8 Browning MT   624H ONVOY SPECTRUM, LLC 648   2021-07-18   

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

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