Among those are the likes of Sean Raggett, Marlon Pack and Joe Rafferty as well as Joe Morrell and Colby Bishop, who have both been linked with Championship switches.
It comes after eight members of the head coach’s side were released at the end of the season following a disappointing eighth-placed finish in League One.
Names including Clark Robertson and Michael Jacobs departed, while Ronan Curtis and Jay Mingi remain in negotiations over fresh terms.
But as Mousinho readies his squad ahead of a potential promotion push, what is the current state of play regarding contracts?
We’ve taken a look at each individual who has a deal beyond this summer and their latest situation at Fratton Park.
Here’s what we found.
5. Sean Raggett
Raggett penned a two-year deal in 2022 after winning the Player of the Season award during the 2021-22 campaign. Mousinho is adamant the defender will be here next term, with his deal set to last until 2024. Photo: Jason Brown
6. Ryley Towler
The centre-back is one of the newest additions to the squad, joining from Bristol City in January. The 21-year-old penned a three-and-a-half year deal, which is set to expire in 2026. Photo: Jason Brown
7. Haji Mnoga
The 21-year-old signed a three-year deal in August 2021, which is set to run until 2024. The central defender is back with the Blues after a loan spell at Aldershot and will be assessed by Mousinho in pre-season as a potential first-team option next term. Photo: Jason Brown
8. Connor Ogilvie
The defender had a 12-month option in his deal triggered at the end of the season, which will now keep him with the Blues until 2024. Ogilvie has started 22 of Mousinho’s 23 games in charge to date - solidifying his place at left-back. Photo: Jason Brown