Both players joined the Reds from the now-defunct Gold Coast United in 2012.
Barker-Daish made 19 appearances for the club, scoring two goals, and Bowles scored one goal in his 23 appearances.
Adelaide coach Josep Gombau thanked both players for their service to the club.
'It has been a pleasure working with them and they always worked hard, event to the last day," said Gombau.
'I wish them both the best of luck for the future and their new clubs that they will join."