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: 660

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-660 A Byram CT   639C ONVOY, LLC - CT 132      
203-660 0 Byram CT   199F BANDWIDTH.COM CLEC, LLC - CT 132   2010-08-07   
203-660 1 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2008-06-01   
203-660 2 Byram CT   145J TERRA NOVA TELECOM INC. 132   2022-04-17   
203-660 3 Byram CT   639C ONVOY, LLC - CT 132   2021-03-04   
203-660 4 Byram CT   624H ONVOY SPECTRUM, LLC 132   2024-10-22   
203-660 5 Byram CT   624H ONVOY SPECTRUM, LLC 132   2024-10-22   
203-660 6 Byram CT   7230 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 132   2003-06-08   
203-660 7 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2008-04-21   
203-660 8 Byram CT   350E YMAX COMMUNICATIONS CORP. - CT 132   2008-06-01   
203-660 9 Byram CT   624H ONVOY SPECTRUM, LLC 132   2025-10-04   

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

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