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: 525

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-525 A Wolverine MI WLVRMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-525 0 Wolverine MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-07-17   
231-525 1 Wolverine MI   829J PAETEC ITEL, LLC 348   2004-02-12   
231-525 2 Wolverine MI   991E BANDWIDTH.COM CLEC, LLC - MI 348   2011-12-30   
231-525 3 Wolverine MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-525 4 Wolverine MI   543C ONVOY, LLCV - MI 348   2013-01-05   
231-525 5 Wolverine MI   543C ONVOY, LLCV - MI 348   2013-03-18   
231-525 6 Wolverine MI   9323 MICHIGAN BELL TEL CO 348      
231-525 7 Wolverine MI   543C ONVOY, LLCV - MI 348   2015-12-31   
231-525 8 Wolverine MI   9323 MICHIGAN BELL TEL CO 348      
231-525 9 Wolverine MI   9323 MICHIGAN BELL TEL CO 348      

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

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