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: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-400 A Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-400 0 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2019-12-11   
231-400 2 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2022-03-04   
231-400 3 Alanson MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-06-18   
231-400 4 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2019-12-11   
231-400 5 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-02-04   
231-400 6 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-02-04   
231-400 8 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-04-28   
231-400 9 Alanson MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-08-12   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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