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: 458

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-458 A Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 0 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 1 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 3 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 4 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 5 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 6 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 7 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 8 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      
406-458 9 Helena MT HLNAMTNORS1  9636 QWEST CORPORATION 648      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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