Lionel Messi and Alexis Sanchez are among the players with their contract situations yet to be fully resolved ahead of the expiry of their current deals next summer.
Barcelona insist Messi has agreed new terms but the Argentine is yet to sign on the dotted line.
Alexis, meanwhile, looks ready to see out of his Arsenal contract after coming close to joining Manchester City in the summer.
Goal has the complete list of potential free agents from all of Europe's top clubs.
Having come so close to joining Manchester City in the summer transfer window, it seems certain Alexis Sanchez is playing his final season at Arsenal.
Mesut Ozil's future is increasingly becoming a concern, too, with the German playmaker yet to commit to a new deal.
Per Mertesacker is set to retire, while the Gunners may wait longer to assess the fitness of the injury-prone Santi Cazorla and Jack Wilshere.
|Miguel Angel Moya||Goalkeeper|
Jose Gimenez has insisted he will be happy to re-sign with Atletico Madrid but is yet to do so, and would likely have his pick of the top clubs in Europe if he was to become a free agent.
Gabi and Juanfran are into their thirties now and may sign short one or two-year extensions later in the season.
Fernando Torres, though, was only handed a 12-month deal in the summer when it became clear that Atleti would have to serve a transfer ban and could be at risk of being cut loose.
Bayern's list of out-of-contract players includes backup goalkeepers, a few young prospects and three first-team players in Arjen Robben, Franck Ribery and Rafinha.
That trio, all of whom are 32 or older, will likely see how the 2017-18 season goes before deciding whether or not to extend their terms by another year.
Two stalwarts of Jurgen Klopp's time in charge, Neven Subotic and Roman Weidenfeller are no longer regular starters for Dortmund.
Weidenfeller, now 37, is the more likely of the two to stay at the club as the backup to Roman Burki.
Chelsea have three depth goalkeepers whose deals are up for renewal.
Willy Caballero and Eduardo could stay on as the second and third-choice options behind Thibaut Courtois but Matej Delac - who is Chelsea's longest-serving player despite spending barely any time at all in England - will move on due to his lack of a work permit.
Miranda remains a key defender for Inter and is reportedly in contract talks already, but Davide Santon has been close to leaving Inter on a couple of occasions and looks set to move on.
Giorgio Chiellini looks set to sign a new deal rather than following Leonardo Bonucci out of the club but rumours have suggested Gianluigi Buffon will retire after the World Cup.
Kwadwo Asamoah and Stephan Lichtsteiner could also leave and Andrea Barzagli, 36, will have to make a decision on his future.
Emre Can has been linked with Juventus and his contract talks continue to drag on.
The German will have the option of signing a pre-contract agreement with another club - aside from Liverpool's English rivals - in January and may wait to explore that possibility.
Yaya Toure is unlikely to see his time at Manchester City extended having lost his place in the lineup once again this season.
Fernandinho's lack of a new deal, though, is more surprising given the Brazilian continues to play a prominent role and will attract plenty of interest elsewhere.
Juan Mata, Ander Herrera and Marouane Fellaini will almost certainly receive offers of new deals and Ashley Young, despite his advancing years, continues to play a role as a versatile experienced head.
Zlatan Ibrahimovic, Daley Blind and Michael Carrick are likely to weigh up their options closer to the end of the season.
Gabriel Paletta is unlikely to stay at Milan and Hachim Mastour looks to be struggling to live up to the billing he has been given as a young player.
Marco Storari could sign on again, though, as Gianluigi Donnarumma's backup.
Joao Moutinho has been through all the ups and downs over the past four years at Monaco and though he is not as integral as he once was, he still provides an influx of creativity.
Whether that role mostly coming off the bench is enough to convince him to stay rather than returning to Portugal or moving elsewhere, though, remains to be seen.
Napoli will be keen to keep Pepe Reina and Faouzi Ghoulam, both of whom are starters at the back.
Camilo Zuniga has been loaned out to Watford and will probably leave, though, while Christian Maggio and Rafael are backups.
|Hatem Ben Arfa||Forward|
Hatem Ben Arfa looks certain to leave having fallen out of favour completely under Unai Emery. He could be sold in January.
If Thiago Motta continues to play a regular role at the base of midfield, though, expect him to sign on for another season.
Real Madrid's young right-back Achraf Hakimi has broken into the first team this season and should be handed extended - and improved - terms before the end of the campaign.
Roma have only backup goalkeeper Bogdan Lobont to make a decision on.
Tottenham are another club with only their No.2 goalkeeper set to become a free agent unless he is tied down to an extension.