This is an alphabetic list of defunct instant messaging platforms, showing the name, when it was discontinued and the type of client.

• AOL Instant Messenger, 1997-2017
• BBM, 2005-2019
• ChatON, 2011-2015
• Emesene, 2013 – MSNP (Microsoft Notification Protocol or Mobile Status Notification Protocol)
• FireChat, 2014-2018
• Gizmo5, 2005-2011 – Multi protocol
• Google Allo, 2016-2019
• Google Hangouts, 2013-2022
• Hike Messenger, 2012-2021
• iChat, 2002-2012
• Meebo, 2005-2012
• Microsoft Kaizala, 2017-2023
• Microsoft Messenger service, 1999-2014
• Mxit, 2005-2016
• MySpaceIM, 2006-2009
• Odigo Messenger, 2002-2004
• ooVoo, 2007-2017
• PowWow, 1994-2001
• Skype Qik, 2014-2016
• Surespot, - 2022
• Talk City, 2002
• Upptalk, 2010-2017
• Xfire, 2003-2015
• Yahoo! Messenger, 1998-2018