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: 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 GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2019-12-11   
231-500 1 Whitehall MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2022-12-02   
231-500 2 Whitehall MI GDRPMIBL41Z  506J TWILIO INTERNATIONAL, INC. 348   2021-07-26   
231-500 3 Whitehall MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-500 4 Whitehall MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-500 5 Whitehall MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2019-12-11   
231-500 6 Whitehall MI GDRPMIBL06Z  770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 348   2023-08-02   
231-500 7 Whitehall MI MSKGMIXKQMD  624H ONVOY SPECTRUM, LLC 348   2021-06-20   
231-500 9 Whitehall MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-08-06   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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