This page lists Firebird versions reached their end-of-life and not maintained by the Firebird Project anymore. Their last official releases continue to be available for download, see the links below.
If you require support for discontinued versions, contact recommended commercial providers of technical support service for Firebird.
For version 2.5, consider HQbird - commercial distribution which supports replication for version 2.5, and supports modern Linux versions as well.
| Version Series | Last Published Release | Appeared | Discontinued |
| v2.5 series | Firebird 2.5.9 | 04 Oct 2010 | 24 Jun 2019 |
| v2.1 series | Firebird 2.1.7 | 18 Apr 2008 | 05 Dec 2014 |
| v2.0 series | Firebird 2.0.7 | 12 Nov 2006 | 12 Apr 2012 |
| v1.5 series | Firebird 1.5.6 | 20 Feb 2004 | 08 Oct 2009 |
| v1.0 series | Firebird 1.0.3 | 12 Mar 2002 | 04 Jun 2003 |