Local Calling Guide

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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 720

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-720 A Muskegon MI MSKGMIXKDS1  0695 FRONTIER NORTH, INC. - MI 348      
231-720 0 Muskegon MI GDRPMIQLX5Y  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 348   2008-02-12   
231-720 1 Muskegon MI MSKGMIXKDS1  0695 FRONTIER NORTH, INC. - MI 348      
231-720 2 Muskegon MI   4632 INTERACTIVE SERVICES NETWORK, INC. 348      
231-720 3 Muskegon MI MSKGMIXKDS1  0695 FRONTIER NORTH, INC. - MI 348      
231-720 4 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2011-01-31   
231-720 5 Muskegon MI GDRQMIBODMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 348   2011-01-13   
231-720 6 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2010-05-03   
231-720 7 Muskegon MI MSKGMIXKDS1  0695 FRONTIER NORTH, INC. - MI 348      
231-720 8 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2010-05-03   
231-720 9 Muskegon MI GDRPMIBL31Z  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348   2011-01-31   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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