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: 374

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-374 A Shelby MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-08-15   
231-374 1 Shelby MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-11-22   
231-374 2 Shelby MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-11-22   
231-374 3 Shelby MI GDRPMIBL41Z  506J TWILIO INTERNATIONAL INC 348   2021-08-16   
231-374 4 Shelby MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-08-15   
231-374 5 Shelby MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-08-15   
231-374 7 Shelby MI GDRPMIBL36Z  624H ONVOY SPECTRUM, LLC 348   2021-08-16   
231-374 8 Shelby MI   543C ONVOY, LLCV - MI 348   2022-03-04   

Last updated: Tue, 15 Nov 2022 00:10:00 UTC

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