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: 352

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-352 A Frankfort MI FRFTMIMNRSA  9323 MICHIGAN BELL TEL CO 348      
231-352 0 Frankfort MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2004-07-17   
231-352 1 Frankfort MI   829J PAETEC ITEL, LLC 348   2004-02-03   
231-352 2 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      
231-352 3 Frankfort MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-09-17   
231-352 4 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      
231-352 5 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      
231-352 6 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      
231-352 7 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      
231-352 8 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      
231-352 9 Frankfort MI   9323 MICHIGAN BELL TEL CO 348      

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

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