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: 974

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-974 A Grant MI GDRPMIBLX8Z  2550 123.NET, INC. 348      
231-974 0 Grant MI GDRPMIBLX8Z  2550 123.NET, INC. 348      
231-974 1 Grant MI   515J IP HORIZON LLC 348   2021-12-31   
231-974 3 Grant MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-974 4 Grant MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-974 6 Grant MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-06-19   
231-974 7 Grant MI GDRPMIBL41Z  506J TWILIO INTERNATIONAL INC 348   2021-07-26   

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

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