Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 309

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-309 A Darien CT BLFDCTAP2MD  5562 METROPCS, INC. 920      
203-309 0 Darien CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2008-03-10   
203-309 1 Darien CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2014-04-19   
203-309 2 Darien CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-08-07   
203-309 3 Darien CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2012-06-02   
203-309 4 Darien CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2012-07-29   
203-309 5 Darien CT   612K CSC VOICE, LLC 920   2011-08-19   
203-309 6 Darien CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2012-09-07   
203-309 7 Darien CT   5562 METROPCS, INC. 920   2007-11-02   
203-309 8 Darien CT   5562 METROPCS, INC. 920   2007-11-02   
203-309 9 Darien CT   5562 METROPCS, INC. 920   2007-11-02   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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