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: 447

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-447 A Holton MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348      
231-447 0 Holton MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2016-02-24   
231-447 1 Holton MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2016-01-29   
231-447 2 Holton MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2016-01-29   
231-447 3 Holton MI GDRPMIBL04Z  543C ONVOY, LLC - MI 348   2016-02-24   
231-447 4 Holton MI   543C ONVOY, LLC - MI 348   2021-03-06   
231-447 5 Holton MI   543C ONVOY, LLC - MI 348   2021-03-06   
231-447 9 Holton MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-01-04   

Last updated: Tue, 04 May 2021 15:04:27 UTC

Sponsored by: VoiceMeUp - Corporate VoIP Services

Like this site? We accept donations via PayPal.