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: 300

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-300 A Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-300 0 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2017-10-22   
231-300 1 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2017-10-22   
231-300 2 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2017-10-22   
231-300 3 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2017-10-22   
231-300 4 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-300 5 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-300 6 Alden MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-06-18   
231-300 8 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2020-09-12   
231-300 9 Alden MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2020-09-12   

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

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