Crawley Town have shown the door to 11 players including Billy Clarke, Paul Jones and Gary Dicker.
Mark Connolly, Paul Connolly, Rory Fallon and Sergio Torres have also not been offered new contracts by the League One club.
Dannie Bulman, Mike Jones, Jamie Proctor and Mat Sadler have been offered new deals and have until the end of May to accept or decline the offers.
The other players who have been released are back-up goalkeeper Johnny Maddison plus youngsters Louie John, Alex Malins and Jonte Smith.
Crawley currently have only five senior players under contract for next season in Kyle McFadzean, Joe Walsh, skipper Josh Simpson, Andy Drury and Connor Essam.
Youth team players Bradley Isaacs and Ryan Richefond have already signed one-year professional contracts.