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: 891

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-891 A Baker MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-891 0 Baker MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-891 1 Baker MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-891 4 Baker MT BLNGMTWE6MD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 650   2024-07-12   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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