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.

Switch: SFLDMIDNLMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
248-595 A Southfield MI 9714 GRID 4 COMMUNICATIONS, INC. - MI 340      
248-657 A Clarkston MI 9714 GRID 4 COMMUNICATIONS, INC. - MI 340      
248-710 A Rochester MI 9714 GRID 4 COMMUNICATIONS, INC. - MI 340      
734-881 A Ann Arbor MI 9714 GRID 4 COMMUNICATIONS, INC. - MI 340      
810-660 A Lapeer MI 9714 GRID 4 COMMUNICATIONS, INC. - MI 340      
810-771 A Grand Blanc MI 9714 GRID 4 COMMUNICATIONS, INC. - MI 340      

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

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