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: 636

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-636 A Howard City MI GDRPMIBLX8Z  2550 123 NET, INC. 348      
231-636 0 Howard City MI GDRPMIBLX8Z  2550 123 NET, INC. 348      
231-636 1 Howard City MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2020-04-18   
231-636 2 Howard City MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2017-05-19   
231-636 3 Howard City MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2013-03-18   
231-636 4 Howard City MI   543C ONVOY, LLC - MI 348   2021-03-06   
231-636 5 Howard City MI   543C ONVOY, LLC - MI 348   2021-03-06   
231-636 7 Howard City MI   508J CENTURYLINK COMMUNICATIONS LLC 348   2015-09-15   

Last updated: Tue, 04 May 2021 15:04:27 UTC

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