The former Sheffield United defender has spent the last 12 years at Goodison Park but confirmed he was leaving on Instagram yesterday.
Sheffield United are rumoured to be interested in bringing the 36-year-old back to Bramall Lane but face reported competition.
The Daily Mail have reported that Stoke City are also eyeing up the former England international.
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Jagielka played nearly 300 times for the Blades and was part of their last season in the Premier League back in 2007.
Writing on his Instagram, Jagielka said: "It's been hard to confirm my situation for next season as that decision hadn’t been fully made by the club until now, unfortunately my journey at Everton has come to an end after 12 fantastic seasons.
"I have been lucky enough to play over 380 games and lucky enough to be club captain for six years.
"All I can say is thanks to all the players I’ve played alongside, all the staff that have helped me in their own way, The chairman and of course the amazing fans.
"Wishing everyone associated with this special club the very best for the future!"
Elsewhere, Chris Wilder’s side have been linked with Manchester United forward James Wilson and Huddersfield Town defender Erik Durm.
The Daily Mail have also reported that Celtic have opened talks over a move for Sheffield United right-back George Baldock.
The 26-year-old made 27 appearances for the Blades last season but only has one year left on his contract.
Celtic reportedly made an initial approach on Tuesday before outlining an opening offer.