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: 550

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-550 A Stamford CT HRFRCT0344Z  866H BARR TEL USA, INC. - CT 920      
475-550 0 Stamford CT   515J IP HORIZON LLC 920   2022-08-04   
475-550 1 Stamford CT   866H BARR TEL USA, INC. - CT 920   2022-04-23   
475-550 2 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2022-10-24   
475-550 3 Stamford CT   073H TELNYX LLC 920   2023-01-23   
475-550 4 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2023-02-12   
475-550 5 Stamford CT   639C ONVOY, LLC - CT 920   2023-08-06   
475-550 6 Stamford CT   639C ONVOY, LLC - CT 920   2022-12-19   
475-550 7 Stamford CT   639C ONVOY, LLC - CT 920   2022-12-19   
475-550 8 Stamford CT   639C ONVOY, LLC - CT 920   2022-12-19   
475-550 9 Stamford CT   639C ONVOY, LLC - CT 920   2022-12-19   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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