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: 478

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-478 A Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-478 0 Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-478 1 Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2010-01-20   
406-478 2 Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2013-10-14   
406-478 3 Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2011-01-07   
406-478 4 Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2011-07-08   
406-478 5 Sidney MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2011-08-11   
406-478 6 Sidney MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2011-08-11   
406-478 7 Sidney MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2014-11-02   
406-478 8 Sidney MT BLNGMTMALMD  994E BANDWIDTH.COM CLEC, LLC - MT 650   2015-06-05   
406-478 9 Sidney MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650   2010-11-06   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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