Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Madison, CT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
203-245 A MDSNCT01RS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 A MDSNCT01RS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 0   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 1   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 2   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 3   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 4   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-03-19   
203-318 5   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 6   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-10-15   
203-318 7   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 920   2011-12-01   
203-318 8   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-318 9   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2013-05-03   
203-350 A HRFRCTCRDS0  7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-350 0   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2008-05-13   
203-350 1   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-350 2   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-02-26   
203-350 3   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-07-03   
203-350 4   508J CENTURYLINK COMMUNICATIONS, LLC 920   2014-04-11   
203-350 5   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920   2007-09-07   
203-350 6   639C ONVOY, LLC - CT 920   2019-08-09   
203-350 7   639C ONVOY, LLC - CT 920   2020-07-05   
203-350 8   199F BANDWIDTH.COM CLEC, LLC - CT 920   2014-06-30   
203-350 9   199F BANDWIDTH.COM CLEC, LLC - CT 920   2008-11-29   
203-421 A MDSNCT02RS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 0   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 1   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 2   318J COMCAST IP PHONE, LLC 920   2014-08-28   
203-421 3   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 4   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 5   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 6   318J COMCAST IP PHONE, LLC 920   2010-09-16   
203-421 7   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 8   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-421 9   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-779 A   829J PAETEC ITEL, LLC 920      
203-779 0   829J PAETEC ITEL, LLC 920      
203-779 1   829J PAETEC ITEL, LLC 920      
203-779 2   829J PAETEC ITEL, LLC 920      
203-779 3   829J PAETEC ITEL, LLC 920      
203-779 4   829J PAETEC ITEL, LLC 920      
203-779 5   318J COMCAST IP PHONE, LLC 920   2004-12-18   
203-779 6   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2011-05-26   
203-779 7   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2012-06-23   
203-779 8   829J PAETEC ITEL, LLC 920   2009-03-30   
203-779 9   5562 METROPCS, INC. 920   2002-12-23   
203-896 A   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920      
203-896 0   199F BANDWIDTH.COM CLEC, LLC - CT 920   2014-06-30   
203-896 1   829J PAETEC ITEL, LLC 920   2005-09-23   
203-896 2   624H ONVOY SPECTRUM, LLC 920   2024-10-22   
203-896 3   624H ONVOY SPECTRUM, LLC 920   2024-10-22   
203-896 4   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2020-10-25   
203-896 5   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2021-03-21   
203-896 6   639C ONVOY, LLC - CT 920   2022-10-07   
203-896 7   199F BANDWIDTH.COM CLEC, LLC - CT 920   2012-09-07   
203-896 8   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2013-05-03   
203-896 9   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2025-05-06   
475-466 A HRFRCT03XSX  516J TON80 COMMUNICATIONS, LLC 920      
475-466 0   515J IP HORIZON LLC 920   2022-07-31   
475-466 1   639C ONVOY, LLC - CT 920   2023-10-14   
475-466 2   639C ONVOY, LLC - CT 920   2023-10-14   
475-466 3   516J TON80 COMMUNICATIONS, LLC 920   2022-03-16   
475-466 4   624H ONVOY SPECTRUM, LLC 920   2022-03-17   
475-466 5   624H ONVOY SPECTRUM, LLC 920   2022-03-17   
475-466 7   639C ONVOY, LLC - CT 920   2023-10-14   
475-466 8   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2023-09-08   
475-466 9   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2022-03-25   
475-522 A HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920      
475-522 0   199F BANDWIDTH.COM CLEC, LLC - CT 920   2015-06-21   
475-522 1   199F BANDWIDTH.COM CLEC, LLC - CT 920   2015-06-21   
475-522 2   639C ONVOY, LLC - CT 920   2019-08-09   
475-522 3   639C ONVOY, LLC - CT 920   2020-07-05   
475-522 4   639C ONVOY, LLC - CT 920   2021-03-04   
475-522 5   639C ONVOY, LLC - CT 920   2021-03-04   
475-522 6   318J COMCAST IP PHONE, LLC 920   2019-09-22   
475-522 7   624H ONVOY SPECTRUM, LLC 920   2021-03-12   
475-522 8   073H TELNYX LLC 920   2018-05-02   
475-522 9   639C ONVOY, LLC - CT 920   2015-06-29   

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

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.