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: 535

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-535 A Walloon Lake MI WNLKMIWLRS1  9323 MICHIGAN BELL TEL CO 348      
231-535 0 Walloon Lake MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-11-14   
231-535 1 Walloon Lake MI   3535 ACD TELECOM, INC. - MI 348   2005-02-18   
231-535 2 Walloon Lake MI   9323 MICHIGAN BELL TEL CO 348      
231-535 4 Walloon Lake MI   817J INTERACTIVE SERVICES NETWORK, INC. 348   2005-09-02   
231-535 6 Walloon Lake MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2007-02-25   
231-535 7 Walloon Lake MI   516C AT&T CORP. 348   2011-08-23   
231-535 8 Walloon Lake MI   829J PAETEC ITEL, LLC 348   2004-02-12   
231-535 9 Walloon Lake MI   543C ONVOY, LLCV - MI 348   2012-06-01   

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

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