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: 502

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-502 A Helena MT HLNAMTHHPS1  008E BRESNAN BROADBAND OF MONTANA, LLC - MT [CHARTER] 648      
406-502 1 Helena MT HLNAMTHHPS1  008E BRESNAN BROADBAND OF MONTANA, LLC - MT [CHARTER] 648   2012-06-01   
406-502 2 Helena MT HLNAMTHHPS1  008E BRESNAN BROADBAND OF MONTANA, LLC - MT [CHARTER] 648   2014-04-30   
406-502 8 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2023-12-13   
406-502 9 Helena MT HLNAMTMAX1X  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 648   2023-12-13   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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