Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 0 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 1 Howell MI   528A FIRST COMMUNICATIONS, LLC - MI 340   2008-07-27   
517-579 2 Howell MI   318J COMCAST IP PHONE LLC 340   2008-12-21   
517-579 3 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 4 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 5 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 6 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 7 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 8 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
517-579 9 Howell MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      

Last updated: Mon, 24 May 2021 01:28:43 UTC

Sponsored by: ISP Telecom

Like this site? We accept donations via PayPal.