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: 447

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-447 A Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-447 0 Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-02-24   
231-447 1 Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-01-29   
231-447 2 Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-01-29   
231-447 3 Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-02-24   
231-447 4 Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-447 5 Holton MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-447 6 Holton MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-06-19   
231-447 7 Holton MI BRSPMI096MD  145J TERRA NOVA TELECOM INC. 348   2021-07-14   
231-447 8 Holton MI GDRPMIBL41Z  506J TWILIO INTERNATIONAL INC 348   2021-07-26   
231-447 9 Holton MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-01-04   

Last updated: Fri, 13 May 2022 22:16:13 UTC

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