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: 221

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-221 A Harbor Springs MI TRCYMIMNWMD  508J CENTURYLINK COMMUNICATIONS, LLC 348      
231-221 0 Harbor Springs MI BRSPMI09DS0  933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2015-12-22   
231-221 1 Harbor Springs MI GDRPMIBLX8Z  2550 123.NET, INC. 348   2016-11-06   
231-221 2 Harbor Springs MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2019-06-13   
231-221 3 Harbor Springs MI BRSPMI09DS0  933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2020-03-18   
231-221 4 Harbor Springs MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-221 5 Harbor Springs MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-03-06   
231-221 6 Harbor Springs MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-06-17   
231-221 7 Harbor Springs MI TRCYMIMNWMD  508J CENTURYLINK COMMUNICATIONS, LLC 348   2015-07-27   
231-221 8 Harbor Springs MI BRSPMI09DS0  933G PEERLESS NETWORK OF MICHIGAN, LLC - MI 348   2019-11-28   
231-221 9 Harbor Springs MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2021-06-17   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

Sponsored by: VoIP.ms

Like this site? We accept donations via PayPal.