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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-421 A South Miles City MT MLCYMTXCRS1  2251 RANGE TEL COOP INC 650      
406-421 0 South Miles City MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2023-03-16   
406-421 1 South Miles City MT   6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2025-04-30   
406-421 2 South Miles City MT BLNGMTWEIMD  6564 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MT 650   2023-12-29   
406-421 5 South Miles City MT MLCYMTXCRS1  2251 RANGE TEL COOP INC 650      
406-421 9 South Miles City MT MLCYMTXCRS1  2251 RANGE TEL COOP INC 650      

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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