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: 516

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-516 A Ansonia-Derby CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2025-04-26   
203-516 0 Ansonia-Derby CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2008-11-29   
203-516 1 Ansonia-Derby CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-10-22   
203-516 2 Ansonia-Derby CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-516 3 Ansonia-Derby CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-516 4 Ansonia-Derby CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-516 5 Ansonia-Derby CT   318J COMCAST IP PHONE, LLC 920   2007-10-25   
203-516 6 Ansonia-Derby CT   829J PAETEC ITEL, LLC 920   2006-04-29   
203-516 7 Ansonia-Derby CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-02-28   
203-516 8 Ansonia-Derby CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2006-09-18   
203-516 9 Ansonia-Derby CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2026-02-17   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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