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: 517

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-517 A Stamford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-517 0 Stamford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-03-20   
203-517 1 Stamford CT HRFRCT03Y0X  829J PAETEC ITEL, LLC 920   2006-11-17   
203-517 2 Stamford CT HRFRCT03Y0X  829J PAETEC ITEL, LLC 920   2007-06-21   
203-517 3 Stamford CT HRFRCT03Y5X  829J PAETEC ITEL, LLC 920   2006-08-07   
203-517 4 Stamford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-517 5 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2006-07-31   
203-517 6 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2006-07-31   
203-517 7 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2006-07-31   
203-517 8 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2006-07-31   
203-517 9 Stamford CT NRWLCT02SMD  612K CSC VOICE, LLC 920   2008-03-07   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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