Northampton have released 13 players after their promotion-winning League Two season, including defender Jordan Turnbull and midfielder Alan McCormack.
Centre-back Turnbull, 25, played 42 times this term, and started Monday’s play-off final at Wembley when they beat Exeter to go up to League One.
Sam Hoskins, Vadaine Oliver and Michael Harriman have been offered new deals to stay with Keith Curle’s side.
Northampton already have 14 players under contract for the 2020-21 season.
Cameron McWilliams, Andy Williams, Ryan Hughes, David Cornell, Jay Williams, Reece Hall-Johnson, Billy Waters, Sean Whaler, Paul Anderson, Bradley Lashley and Jack Newell are the other players who have been let go.
“This is a difficult summer with the impact of Covid-19 on the industry and we have been very transparent about that from the very start with the players,” Curle told the club website.
“The industry is having to make adjustments and that is being reflected across the game. As a club, it is important show good housekeeping in these difficult times.”