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: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-303 A Wallingford CT HRFRCTCRDS0  7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-303 0 Wallingford CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-303 1 Wallingford CT   318J COMCAST IP PHONE, LLC 920   2017-09-14   
203-303 2 Wallingford CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-303 3 Wallingford CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-303 4 Wallingford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-09-09   
203-303 5 Wallingford CT   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 920   2003-06-18   
203-303 6 Wallingford CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-303 7 Wallingford CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2006-06-30   
203-303 8 Wallingford CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-01-10   
203-303 9 Wallingford CT   073H TELNYX LLC 920   2018-05-02   

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

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