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: 574

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-574 A Silvertip MT POWLWYMARS1  9636 QWEST CORPORATION 654      
406-574 0 Silvertip MT CHYNWYRF1MD  073H TELNYX LLC 654   2018-07-25   
406-574 1 Silvertip MT POWLWYMARS1  9636 QWEST CORPORATION 654      
406-574 2 Silvertip MT CHYNWYMAX2X  453F ONVOY, LLC - MT 654   2021-07-05   
406-574 3 Silvertip MT POWLWYMARS1  9636 QWEST CORPORATION 654      
406-574 4 Silvertip MT CHYNWYMAEMD  9415 LEVEL 3 COMMUNICATIONS, LLC - MT 654   2023-03-02   
406-574 5 Silvertip MT CHYNWYMAXKX  478J NUSO, LLC 654   2023-12-09   
406-574 6 Silvertip MT CHYNWYMAXKX  478J NUSO, LLC 654   2023-12-09   
406-574 7 Silvertip MT CHYNWYMAXAX  508J CENTURYLINK COMMUNICATIONS, LLC 654   2015-03-18   
406-574 8 Silvertip MT CHYNWYMAXKX  478J NUSO, LLC 654   2020-10-11   

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

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