Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Alzada, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-828 A ALZDMTXCRS1  2251 RANGE TEL COOP INC 650      
406-828 4   2251 RANGE TEL COOP INC 650      
406-828 8   145J TERRA NOVA TELECOM INC. 650   2025-08-29   
406-938 A BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-938 0   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-938 3   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2018-12-17   
406-938 4   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-938 7   6010 NEW CINGULAR WIRELESS PCS, LLC 650   2021-08-27   
406-938 8   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      
406-938 9   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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