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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-421 A Traverse City MI   792K CHARTER IP ENABLED SERVICES, LLC 348      
231-421 0 Traverse City MI GDRPMIBLXTZ  3535 ACD TELECOM, INC. - MI 348   2005-02-18   
231-421 1 Traverse City MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2007-02-25   
231-421 2 Traverse City MI GDRPMIBL52Z  829J PAETEC ITEL, LLC 348   2005-09-22   
231-421 3 Traverse City MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2008-02-25   
231-421 4 Traverse City MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2011-01-10   
231-421 5 Traverse City MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2008-08-21   
231-421 6 Traverse City MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2006-08-29   
231-421 7 Traverse City MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2006-08-29   
231-421 8 Traverse City MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2009-10-04   
231-421 9 Traverse City MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2010-12-02   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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