Local Calling Guide

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

NXX: 500

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-500 A Whitehall MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-500 0 Whitehall MI   543C ONVOY, LLCV - MI 348   2019-12-11   
231-500 1 Whitehall MI   543C ONVOY, LLCV - MI 348   2022-12-02   
231-500 3 Whitehall MI   543C ONVOY, LLCV - MI 348   2021-03-06   
231-500 4 Whitehall MI   543C ONVOY, LLCV - MI 348   2021-03-06   
231-500 5 Whitehall MI   543C ONVOY, LLCV - MI 348   2019-12-11   
231-500 6 Whitehall MI   770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 348   2023-08-02   
231-500 7 Whitehall MI   624H ONVOY SPECTRUM, LLC 348   2021-06-20   
231-500 8 Whitehall MI   145J TERRA NOVA TELECOM INC. 348   2025-07-12   
231-500 9 Whitehall MI   543C ONVOY, LLCV - MI 348   2023-08-06   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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