Ipswich have accepted offers for Jon Stead, Alex Bruce and Owen Garvan, and are still looking to sign Marton Fulop from Sunderland.
Striker Stead is the target of several clubs, including Premier League debutants Blackpool, while defender Bruce is in talks with fellow Championship side Leeds and midfielder Garvan could make the move to Crystal Palace.
Manager Roy Keane told Town's official website: "A fee has been accepted for all three and we have given them permission to talk to the clubs, it's up to the players now to agree a deal."
Keane also said he expects to know within the next 48 hours whether negotiations with Sunderland goalkeeper Fulop have been successful.
Hungary international Fulop, who joined the Black Cats three years ago, spent the final part of last season on loan at Manchester City.
"I want to bring in another keeper and we've been talking to Marton," added Keane.
"I think he wants to come but there are things to sort out and he is one of two targets were have."
Meanwhile, winger Luciano Civelli is facing just 10 days on the sidelines after suffering a jarred knee during Town's pre-season friendly against Bury on Wednesday.