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: 638

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-638 A Hardin MT CWAGMTXCDS0  2250 PROJECT TEL. CO., INC. 650      
406-638 1 Hardin MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2014-09-05   
406-638 2 Hardin MT CWAGMTXCDS0  2250 PROJECT TEL. CO., INC. 650      
406-638 3 Hardin MT CWAGMTXCDS0  2250 PROJECT TEL. CO., INC. 650      
406-638 4 Hardin MT CWAGMTXCDS0  2250 PROJECT TEL. CO., INC. 650      
406-638 5 Hardin MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2021-07-05   
406-638 6 Hardin MT BLNGMTWEBMD  771G TELEPORT COMMUNICATIONS AMERICA MT - LLC 650   2020-08-07   
406-638 7 Hardin MT CWAGMTXCDS0  2250 PROJECT TEL. CO., INC. 650      
406-638 8 Hardin MT BLNGMTAS9MD  453F ONVOY, LLC - MT 650   2021-07-05   
406-638 9 Hardin MT CWAGMTXCDS0  2250 PROJECT TEL. CO., INC. 650      

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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