The Blades can confirm the retained list, which has been submitted to the Football League.
Mark Howard, Bob Harris and Terry Kennedy's contract options have been taken up and they will remain at Bramall Lane next season.
However, Matt Hill, Shaun Miller, Chris Porter, Darryl Westlake, Sean McGinty, Elliott Whitehouse, Jasper Johns, Jordan Hodder and Jahmal Smith have been released.
Blades boss Nigel Clough commented: "There have been some tough decisions but we need to make way for new faces. It is difficult, especially when you are dealing with good characters.
"Chris Porter's situation is a little different. We've not taken up his option and because of that he has to go on the list of free transfers but we are still talking with regards to a new contract."
It has already been announced that a total of 11 players have been offered professional contracts following successful scholarships at the Academy.