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: 889

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-889 A Onekama MI ONKMMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-889 0 Onekama MI   9323 MICHIGAN BELL TEL CO 348      
231-889 1 Onekama MI   3535 ACD TELECOM, INC. - MI 348   2005-02-17   
231-889 2 Onekama MI   624H ONVOY SPECTRUM, LLC 348   2021-06-20   
231-889 3 Onekama MI   9323 MICHIGAN BELL TEL CO 348      
231-889 4 Onekama MI   9323 MICHIGAN BELL TEL CO 348      
231-889 5 Onekama MI   9323 MICHIGAN BELL TEL CO 348      
231-889 6 Onekama MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2006-05-31   
231-889 7 Onekama MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2007-02-25   
231-889 8 Onekama MI   829J PAETEC ITEL, LLC 348   2004-02-12   
231-889 9 Onekama MI   9323 MICHIGAN BELL TEL CO 348      

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

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