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: 457

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-457 A Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 0 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 1 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 2 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 3 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 4 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 5 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 7 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 8 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      
406-457 9 Helena MT HLNAMTMADS0  9636 QWEST CORPORATION 648      

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

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