A total of eight senior players will see their current deals expire at the end of June, while a further three are only contracted to Boro on loan.
We take a closer look at the contractual situation of 11 Boro players who face an uncertain future on Teesside – scroll down and flick through the pages to see them:
5. Aynsley Pears - out of contract this summer with an option of an extra year
After tying down several of their young assets, Boro have been in talks with Pears for a number of weeks. It's believed the club have an option to extend the goalkeeper's contract by an extra year, yet the recent delay is a slight concern. Photo: Bradley Collyer
6. Ryan Shotton - out of contract this summer
After missing a large part of the campaign through injury, it seems unlikely the 31-year-old defender will be offered a new deal. Shotton has performed well since his return to the side but may not be a first-team regular when everyone is fit. Photo: Owen Humphreys
7. Adam Clayton - out of contract this summer
A player with plenty of experience who is into his sixth full season at the club. The midfielder has been in and out of the side this season though, which may make it hard to justify a new deal for the 31-year-old. Photo: Bradley Collyer
8. Rudy Gestede - out of contract this summer
Despite some impressive performances in recent weeks, it would be a big surprise to see Gestede extend his Boro contract. Things haven't worked out for the towering frontman on Teesside with injuries contributing to his struggles. Photo: Owen Humphreys