Fabian Wilnis, Jaime Peters, Michael Synnott and Sammy Moore have all agreed to sign their new contracts with the Blues. Defender Ian Miller has been offered another one-year deal at Portman Road, not a three-year contract as previously reported.
Peters, currently away with the Canada U20 squad, will sign his deal once he has secured a new work permit. Wilnis, Synnott and Moore have all been offered another year with the Blues.
Boss Jim Magilton has confirmed that Darren Currie, Martin Brittain, Scott Barron and James Krause have been released, while the Blues will listen to offers for Spanish full-back Sito, who has a year left on his contract.
Magilton told the club site the reasons behind his decisions: "Fabian is a terrific professional and has done a great job for us and deserves another year here.
"He has shown he can still play at this level and offers competition for places right across the back four.
"With Sammy and Michael, we will be keeping them on and it will be a case of seeing how they do in pre-season and then maybe looking for them to take the next step forward, which is gaining first team experience.
"James, Martin and Scott are great lads, but they are at an age now when they need to be playing regularly at first team level.
"I was in the same situation myself at Liverpool when I was told I could move on, but I was determined to go out and make a name for myself somewhere else and I'm sure these lads will show the same desire. I wish them all the success in the world.
"Sito is another terrific lad and he is still contracted to this club for another year, but I have told him that if clubs come in for him we will talk to them. He's another who needs to be out there on the pitch every week."
Magilton is yet to speak to striker Darryl Knights, who like Brittain is currently on loan at Yeovil, and plans to hold talks with the 19-year-old after the Glovers' play-off campaign.
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