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: 278

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-278 A Hesperia MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348      
231-278 7 Hesperia MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2020-12-26   
231-278 8 Hesperia MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2020-12-26   

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

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