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: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-437 A Charlevoix MI GDRPMIBLXDZ  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348      
231-437 0 Charlevoix MI GDRPMIBLXDZ  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 348      
231-437 1 Charlevoix MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2016-03-21   
231-437 2 Charlevoix MI GDRPMIBL15Z  516C AT&T CORP. 348   2011-08-23   
231-437 3 Charlevoix MI GFTPMIEF1MD  351D CHARTER FIBERLINK - MICHIGAN, LLC - MI 348   2007-02-25   
231-437 4 Charlevoix MI GDRPMIBL06Z  770E TELEPORT COMMUNICATIONS AMERICA, LLC - MI 348   2007-12-11   
231-437 5 Charlevoix MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2013-04-01   
231-437 6 Charlevoix MI GFTPMIEF1MD  351D CHARTER FIBERLINK - MICHIGAN, LLC - MI 348   2014-08-09   
231-437 7 Charlevoix MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2014-09-01   
231-437 8 Charlevoix MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2020-11-14   
231-437 9 Charlevoix MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2020-11-14   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

Sponsored by: Callcentric - VoIP Internet phone service

Like this site? We accept donations via PayPal.