Defenders Paul McShane and Liam Rosenior have been offered new contracts along with goalkeeper Mark Oxley, while Abdoulaye Faye has automatically triggered a new 12-month deal after reaching a pre-agreed number of appearances.
But 12 players have been shown the door to make way for new arrivals, with long-serving defender Andy Dawson and former Arsenal trainee Jay Simpson the most prominent.
Also leaving the club are Paul McKenna, Seyi Olofinjana, Sonny Bradley, Lewis Clarkson, Mark Cullen, Jamie Devitt, Kealan Dillon, Daniel East, Daniel Emerton and Francis McCaffrey.
Six academy players - Daniel Chambers, Benjamin Clappison, Joseph Cracknell, Matthew Dixon, Paul McElroy and Sam Topliss - have earned professional contracts, but Thomas Davie, Bradley Ricketts and Joel Sutton will move on.
- Abdoulaye Faye
- Andy Dawson
- Mark Oxley
- Seyi Olofinjana
- Liam Rosenior