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: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 424

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-424 A Darien CT BLFDCTAP2MD  5562 METROPCS, INC. 920      
203-424 0 Darien CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2008-11-29   
203-424 1 Darien CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-02-26   
203-424 2 Darien CT   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2013-05-03   
203-424 3 Darien CT   5562 METROPCS, INC. 920   2011-03-23   
203-424 4 Darien CT   5562 METROPCS, INC. 920   2011-03-23   
203-424 5 Darien CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920   2007-09-07   
203-424 6 Darien CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2011-03-23   
203-424 7 Darien CT   5562 METROPCS, INC. 920   2007-09-14   
203-424 8 Darien CT   5562 METROPCS, INC. 920   2007-09-14   
203-424 9 Darien CT   5562 METROPCS, INC. 920   2007-09-14   

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

Sponsored by: FiberConX Communications Ltd.

Like this site? We accept donations via PayPal.