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: 571

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-571 A Muskegon MI MSKGMIXKDS1  0695 FRONTIER NORTH, INC. - MI 348      
231-571 0 Muskegon MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2005-04-02   
231-571 1 Muskegon MI   543C ONVOY, LLC - MI 348   2015-12-09   
231-571 2 Muskegon MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2004-10-17   
231-571 3 Muskegon MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2004-10-17   
231-571 4 Muskegon MI   6664 SPRINT SPECTRUM L.P. 348   2009-01-19   
231-571 5 Muskegon MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2005-04-02   
231-571 6 Muskegon MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 348   2005-04-02   
231-571 7 Muskegon MI   6664 SPRINT SPECTRUM L.P. 348   2007-11-29   
231-571 8 Muskegon MI   6664 SPRINT SPECTRUM L.P. 348   2007-11-29   
231-571 9 Muskegon MI   0695 FRONTIER NORTH, INC. - MI 348      

Last updated: Sun, 04 Apr 2021 19:28:27 UTC

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