Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 424

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-424 A Carr MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348      
231-424 4 Carr MI   145J TERRA NOVA TELECOM INC. 348   2025-05-31   
231-424 7 Carr MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348   2005-03-20   

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

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