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: 388

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
475-388 A Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2025-03-24   
475-388 0 Stamford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2025-03-25   
475-388 1 Stamford CT   639C ONVOY, LLC - CT 920   2025-05-10   
475-388 9 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2025-03-24   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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