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: 514

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-514 A Culbertson MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650      
406-514 0 Culbertson MT BLNGMTMAMMD  6010 NEW CINGULAR WIRELESS PCS, LLC 650   2010-12-17   
406-514 1 Culbertson MT   6010 NEW CINGULAR WIRELESS PCS, LLC 650   2025-02-03   

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

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