We only provide a migration path from Joomla 4.3 to Joomla 5. If you are using an earlier Joomla 4.x version please upgrade to Joomla 4.3 first.
You cannot migrate from Joomla 4 to Joomla 6 or later. You will need to migrate to Joomla 5 first.
This section will be written when Joomla 5.0 approaches its release date which is currently set for October 2023.
Our plan is to have a version of Akeeba Backup 9 which will be compatible with Joomla 4.3 and 5.x, therefore requiring no migration (at least for moving to Joomla 5.0). If we need to drop Joomla 4 support to support new features in Joomla 5 and beyond we will increase the major version of Akeeba Backup, introduce a migration step if necessary, and document it here.