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: 354

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-354 A Coral MI TRFNMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-354 0 Coral MI   829J PAETEC ITEL, LLC 348   2006-01-12   
231-354 1 Coral MI   3535 ACD TELECOM, INC. - MI 348   2004-10-22   
231-354 2 Coral MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-07-16   
231-354 3 Coral MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-354 4 Coral MI   624H ONVOY SPECTRUM, LLC 348   2021-06-18   
231-354 5 Coral MI   516C AT&T CORP. 348   2011-08-23   
231-354 6 Coral MI   9323 MICHIGAN BELL TEL CO 348      
231-354 7 Coral MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2005-12-10   
231-354 8 Coral MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2007-03-19   
231-354 9 Coral MI   543C ONVOY, LLCV - MI 348   2012-12-29   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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