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: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-440 A Baldwin MI GDRPMIBLX8Z  2550 123.NET, LLC 348      
231-440 0 Baldwin MI GDRPMIBLX8Z  2550 123.NET, LLC 348      
231-440 1 Baldwin MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2015-08-02   
231-440 2 Baldwin MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-04-11   
231-440 3 Baldwin MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-04-11   
231-440 4 Baldwin MI BRSPMI09DS0  933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2019-06-09   
231-440 6 Baldwin MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-440 7 Baldwin MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2017-10-04   
231-440 8 Baldwin MI BRSPMI09DS0  933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2015-12-20   
231-440 9 Baldwin MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2015-08-13   

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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