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: 389

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-389 A Harrietta MI HRTAMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-389 0 Harrietta MI   9323 MICHIGAN BELL TEL CO 348      
231-389 1 Harrietta MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-11-12   
231-389 2 Harrietta MI   9323 MICHIGAN BELL TEL CO 348      
231-389 3 Harrietta MI   543C ONVOY, LLCV - MI 348   2021-07-11   
231-389 4 Harrietta MI   3535 ACD TELECOM, INC. - MI 348   2005-02-11   
231-389 5 Harrietta MI   543C ONVOY, LLCV - MI 348   2012-06-01   
231-389 6 Harrietta MI   543C ONVOY, LLCV - MI 348   2012-12-30   
231-389 7 Harrietta MI   516C AT&T CORP. 348   2011-08-23   
231-389 8 Harrietta MI   543C ONVOY, LLCV - MI 348   2021-04-25   
231-389 9 Harrietta MI   543C ONVOY, LLCV - MI 348   2013-03-18   

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

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