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: 813

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-813 A Byram CT WHPLNY02DS5  7140 TC SYSTEMS, INC. - NY 132      
203-813 0 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2009-09-15   
203-813 1 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2009-02-06   
203-813 2 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2009-09-15   
203-813 3 Byram CT   612K CSC VOICE, LLC 132   2005-04-22   
203-813 4 Byram CT   639C ONVOY, LLC - CT 132   2019-02-18   
203-813 5 Byram CT   639C ONVOY, LLC - CT 132   2016-04-24   
203-813 6 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2008-10-10   
203-813 7 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2008-06-18   
203-813 8 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2008-06-18   
203-813 9 Byram CT   7140 TC SYSTEMS, INC. - NY 132      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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