Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 475 [Rate centres in NPA 475] [Dial plan for NPA 475]

NXX: 275

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-275 A Byram CT NYCMNYBXDSL  639C ONVOY, LLC - CT 132      
475-275 0 Byram CT   639C ONVOY, LLC - CT 132   2016-04-24   
475-275 1 Byram CT   199F BANDWIDTH.COM CLEC, LLC - CT 132   2016-07-18   
475-275 2 Byram CT   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 132   2017-12-23   
475-275 3 Byram CT   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 132   2018-11-04   
475-275 4 Byram CT   639C ONVOY, LLC - CT 132   2018-07-07   
475-275 5 Byram CT   866H BARR TEL USA, INC. - CT 132   2016-07-18   
475-275 6 Byram CT   639C ONVOY, LLC - CT 132   2019-04-29   
475-275 7 Byram CT   639C ONVOY, LLC - CT 132   2016-04-22   
475-275 8 Byram CT   639C ONVOY, LLC - CT 132   2016-04-22   
475-275 9 Byram CT   639C ONVOY, LLC - CT 132   2019-04-29   

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

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