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: 810 [Rate centres in NPA 810] [Dial plan for NPA 810]

NXX: 740

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-740 A St Clair MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-740 0 St Clair MI   516J TON80 COMMUNICATIONS, LLC 340   2022-04-05   
810-740 2 St Clair MI   7279 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MI 340   2006-04-21   
810-740 3 St Clair MI   3535 ACD TELECOM, INC. - MI 340   2005-12-10   
810-740 4 St Clair MI   6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340   2006-05-06   
810-740 5 St Clair MI   516C AT&T CORP. 340   2011-11-30   
810-740 6 St Clair MI   543C ONVOY, LLCV - MI 340   2012-10-13   
810-740 7 St Clair MI   543C ONVOY, LLCV - MI 340   2013-01-31   
810-740 8 St Clair MI   624H ONVOY SPECTRUM, LLC 340   2021-06-15   

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

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.