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: 646

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-646 A Branford CT   639C ONVOY, LLC - CT 920      
203-646 0 Branford CT   624H ONVOY SPECTRUM, LLC 920   2021-03-12   
203-646 1 Branford CT   639C ONVOY, LLC - CT 920   2023-05-06   
203-646 2 Branford CT   506J TWILIO INTERNATIONAL, INC. 920   2021-03-28   
203-646 3 Branford CT   639C ONVOY, LLC - CT 920   2020-11-22   
203-646 4 Branford CT   639C ONVOY, LLC - CT 920   2020-11-22   
203-646 5 Branford CT   639C ONVOY, LLC - CT 920   2021-03-04   
203-646 6 Branford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2011-06-01   
203-646 7 Branford CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2011-03-29   
203-646 8 Branford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2011-06-01   
203-646 9 Branford CT   145J TERRA NOVA TELECOM INC. 920   2025-05-05   

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

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