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: 850

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-850 A Norwalk CT HRFRCT0344Z  866H BARR TEL USA, INC. - CT 920      
475-850 0 Norwalk CT HRFRCTBCDS1  639C ONVOY, LLC - CT 920   2024-12-15   
475-850 1 Norwalk CT HRFRCT0344Z  866H BARR TEL USA, INC. - CT 920   2022-04-23   
475-850 2 Norwalk CT NRWLCT02Y0X  425J CSC WIRELESS, LLC 920   2023-08-20   
475-850 3 Norwalk CT NRWLCT02Y0X  425J CSC WIRELESS, LLC 920   2023-10-20   
475-850 4 Norwalk CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2025-02-19   
475-850 5 Norwalk CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2025-02-19   
475-850 7 Norwalk CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920   2024-03-25   
475-850 8 Norwalk CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2024-02-09   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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