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: 566

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-566 A Stanford MT FTBNMTXCDS0  3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 1 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 2 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 3 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 4 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 5 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 7 Stanford MT   9415 LEVEL 3 COMMUNICATIONS, LLC - MT 648   2026-06-09   
406-566 8 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      
406-566 9 Stanford MT   3310 TRIANGLE TEL. COOP. ASSN., INC. 648      

Last updated: Sat, 02 May 2026 12:20:53 UTC

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