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: DTRTMIVWDMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
248-248 A Northville MI 624H ONVOY SPECTRUM, LLC 340      
313-708 A Detroit Zone 2 MI 624H ONVOY SPECTRUM, LLC 340      
313-710 A Detroit Zone 1 MI 624H ONVOY SPECTRUM, LLC 340      
313-787 A Detroit Zone 6 MI 624H ONVOY SPECTRUM, LLC 340      
586-358 A Utica MI 624H ONVOY SPECTRUM, LLC 340      
734-290 A Dundee MI 624H ONVOY SPECTRUM, LLC 340      
734-584 A Gregory MI 624H ONVOY SPECTRUM, LLC 340      
810-380 A Flushing MI 624H ONVOY SPECTRUM, LLC 340      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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