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: 276

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-276 A Interlochen MI GRWNMIMNRS0  9323 MICHIGAN BELL TEL CO 348      
231-276 0 Interlochen MI   9323 MICHIGAN BELL TEL CO 348      
231-276 1 Interlochen MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-11-12   
231-276 2 Interlochen MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2007-04-08   
231-276 3 Interlochen MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2007-02-25   
231-276 4 Interlochen MI   9323 MICHIGAN BELL TEL CO 348      
231-276 5 Interlochen MI   9323 MICHIGAN BELL TEL CO 348      
231-276 6 Interlochen MI   9323 MICHIGAN BELL TEL CO 348      
231-276 7 Interlochen MI   9323 MICHIGAN BELL TEL CO 348      
231-276 8 Interlochen MI   829J PAETEC ITEL, LLC 348   2004-02-03   
231-276 9 Interlochen MI   9323 MICHIGAN BELL TEL CO 348      

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

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