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: 999

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-999 A Central Lake MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348      
231-999 2 Central Lake MI   543C ONVOY, LLC - MI 348   2021-03-06   
231-999 3 Central Lake MI   543C ONVOY, LLC - MI 348   2021-03-06   
231-999 7 Central Lake MI   508J CENTURYLINK COMMUNICATIONS LLC 348   2015-10-21   
231-999 8 Central Lake MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2015-10-19   
231-999 9 Central Lake MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2015-10-19   

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

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