Peterborough manager Gary Johnson has placed Sergio Torres, Ben Wright and Kwesi Appiah on the transfer list.
The trio are not in Johnson's future plans and have joined defender Exodus Geohaghon on the list.
Left-back Danny Andrew will not be offered a new contract and is expected to leave.
Johnson has yet to speak with the large number of players out on loan at other clubs, including Shaun Batt, Scott Rendell, Rene Howe and Toumani Diagouraga.
He said: "I will speak to them when the season concludes for them in the coming days and let them know my thoughts."