Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 453F ONVOY, LLC - MT

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NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
406-991 8 Marion MT GRFLMTMA7MD  648   2011-03-05   
406-992 A Helena MT   648      
406-992 0 Helena MT   648   2025-05-17   

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Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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