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: 903

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-903 A Muskegon MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348      
231-903 0 Muskegon MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2005-01-08   
231-903 1 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2006-07-08   
231-903 2 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2006-10-19   
231-903 3 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2006-12-05   
231-903 4 Muskegon MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348      
231-903 5 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2005-06-10   
231-903 6 Muskegon MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2012-06-28   
231-903 7 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2005-06-10   
231-903 8 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2005-06-10   
231-903 9 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2005-06-10   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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