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: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 819

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-819 A Tustin MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-819 0 Tustin MI   543C ONVOY, LLCV - MI 348   2014-11-13   
231-819 1 Tustin MI   543C ONVOY, LLCV - MI 348   2014-11-13   
231-819 2 Tustin MI   543C ONVOY, LLCV - MI 348   2016-03-22   
231-819 3 Tustin MI   543C ONVOY, LLCV - MI 348   2016-03-22   
231-819 4 Tustin MI   046L CLEAR RATE COMMUNICATIONS, LLC 348   2016-08-31   
231-819 5 Tustin MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2016-12-11   
231-819 6 Tustin MI   508J CENTURYLINK COMMUNICATIONS, LLC 348   2017-10-05   
231-819 7 Tustin MI   543C ONVOY, LLCV - MI 348   2014-11-05   
231-819 8 Tustin MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2018-12-28   
231-819 9 Tustin MI   933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2015-01-10   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.