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: 579

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
517-579 A Howell MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 0 Howell MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 1 Howell MI SFLDMIMKNMD  460K FIRST COMMUNICATIONS, LLC 340   2008-07-27   
517-579 2 Howell MI WAYNMIMNXUX  318J COMCAST IP PHONE, LLC 340   2008-12-21   
517-579 3 Howell MI SFLDMIMK5MD  939H COMMIO, LLC 340   2021-10-11   
517-579 4 Howell MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 5 Howell MI SFLDMIMK5MD  939H COMMIO, LLC 340   2021-10-11   
517-579 6 Howell MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 7 Howell MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 8 Howell MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 9 Howell MI SFLDMIMK5MD  939H COMMIO, LLC 340   2021-10-11   

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

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