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: 928

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-928 A Fremont MI FRMTMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-928 0 Fremont MI   9323 MICHIGAN BELL TEL CO 348      
231-928 1 Fremont MI   9323 MICHIGAN BELL TEL CO 348      
231-928 2 Fremont MI   9323 MICHIGAN BELL TEL CO 348      
231-928 3 Fremont MI   9323 MICHIGAN BELL TEL CO 348      
231-928 4 Fremont MI   9323 MICHIGAN BELL TEL CO 348      
231-928 5 Fremont MI   543C ONVOY, LLCV - MI 348   2012-02-22   
231-928 6 Fremont MI   9245 CYNERGYCOMM.NET, INC. - MI 348   2005-08-28   
231-928 7 Fremont MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-09-17   
231-928 8 Fremont MI   543C ONVOY, LLCV - MI 348   2013-03-18   
231-928 9 Fremont MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2015-09-10   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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