Local Calling Guide

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NPA: 475 [Rate centres in NPA 475] [Dial plan for NPA 475]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-666 A Westport CT HRFRCT0380Z  539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920      
475-666 0 Westport CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2016-07-10   
475-666 1 Westport CT HRFRCT03HMD  073H TELNYX LLC 920   2017-06-05   
475-666 2 Westport CT HRFRCT0380Z  539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2018-10-21   
475-666 3 Westport CT NWHNCT02XJX  624H ONVOY SPECTRUM, LLC 920   2021-03-12   
475-666 4 Westport CT HRFRCT0383Z  7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920   2018-12-07   
475-666 5 Westport CT HRFRCTBCDS1  639C ONVOY, LLC - CT 920   2018-10-15   
475-666 6 Westport CT HRFRCT0380Z  539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2016-06-12   
475-666 7 Westport CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2016-10-04   
475-666 8 Westport CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2016-09-28   
475-666 9 Westport CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2016-08-26   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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