Luke Daniels, Scott Wiseman, Scott Laird, David Mirfin, Luke Williams, Dominic Vose, Paddy Madden, Kevin van Veen, Neal Bishop, Joe Anyon, Stephen Dawson, Hakeeb Adelakun, Conor Townsend, Jack King, Charlie Goode, Tom Hopper, Murray Wallace, Jamie Ness, Kyle Wootton, Levi Sutton and Jordan Clarke are all under contract with the club beyond this summer.
Meanwhile, Jack Dyche and Noel Burdett have graduated from the youth setup to join the first team squad this summer.
Iron manager Graham Alexander said: “All of these players have shown their qualities for Scunthorpe United and added to the club’s success. These are just the scenarios that happen at every club at the end of every season.
“We are fortunate to have a lot of players under contract and they’ve shown what a good team they can be. We genuinely wish the four players leaving us all the best. They were great to talk to and they understood the reasons.
“I’m sure we will come up against one or two of them in the future.”
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