Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 517 [Rate centres in NPA 517] [Dial plan for NPA 517]

NXX: 522

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-522 A Grass Lake MI GRLKMIXGDS0  0695 FRONTIER NORTH, INC. - MI 346      
517-522 0 Grass Lake MI   817J INTERACTIVE SERVICES NETWORK, INC. 346   2005-09-03   
517-522 1 Grass Lake MI   770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 346   2016-03-21   
517-522 2 Grass Lake MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 346   2009-12-07   
517-522 3 Grass Lake MI   0695 FRONTIER NORTH, INC. - MI 346      
517-522 4 Grass Lake MI   0695 FRONTIER NORTH, INC. - MI 346      
517-522 5 Grass Lake MI   0695 FRONTIER NORTH, INC. - MI 346      
517-522 6 Grass Lake MI   0695 FRONTIER NORTH, INC. - MI 346      
517-522 7 Grass Lake MI   543C ONVOY, LLCV - MI 346   2007-03-05   
517-522 8 Grass Lake MI   0695 FRONTIER NORTH, INC. - MI 346      
517-522 9 Grass Lake MI   2550 123.NET, LLC 346   2017-04-03   

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

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