Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 356

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-356 A Butte NE OMAKNEYW6MD  965H FRACTEL, LLC 644      
531-356 7 Butte NE OMAKNEYW6MD  965H FRACTEL, LLC 644   2021-09-17   
531-356 9 Butte NE OMAKNEYW6MD  965H FRACTEL, LLC 644   2021-09-17   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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