Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 571

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-571 A Westport CT NWHNCT02X5X  7421 AT&T - LOCAL 920      
203-571 0 Westport CT   145J TERRA NOVA TELECOM INC. 920   2025-10-16   
203-571 1 Westport CT   829J PAETEC ITEL, LLC 920   2001-05-17   
203-571 2 Westport CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2016-01-19   
203-571 3 Westport CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2014-05-02   
203-571 4 Westport CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2014-05-02   
203-571 5 Westport CT   7421 AT&T - LOCAL 920      
203-571 6 Westport CT   829J PAETEC ITEL, LLC 920   2006-05-25   
203-571 7 Westport CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2005-11-28   
203-571 8 Westport CT   5562 METROPCS, INC. 920   2002-12-11   
203-571 9 Westport CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2016-01-19   

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

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