Manager Alan Archibald will set about trying to extend players' contracts after Partick Thistle's Scottish Premiership status was secured.
A 3-0 win over St Mirren ensured Thistle will finish above the bottom two places.
O'Donnell, Kallum Higginbotham, Abdul Osman, Scott Fox and Steven Lawless are just some of the Firhill players whose deals expire in the summer.
However, the Jags' boss is "resigned" to losing right-back Stephen O'Donnell.
"We can start speaking to them right away," he told BBC Scotland.
"The lads know what league they're going to be in if they still want to be here and we'll push on with that as quick as we can."
O'Donnell turned down a move to Blackpool earlier in January.
"I think Stephen wants to go and ply his trade in England if he can and I don't think he'll be short of offers," said Archibald, whose team claimed a third consecutive win.
"He's more than welcome to stay at the club, he knows that. He's come on in leaps and bounds but there's every chance we'll lose him."
Ryan Stevenson, Kris Doolan and Lawless were all on target for Thistle, who were frustrated by a mix of poor finishing and decent Buddies defending in the first half.
"It looked like it was going to be one of those days," added Archibald.
"They had a penalty claim and I've seen them given, but the lads stuck at it and got their just rewards. Very pleased with the clean sheet as well.
"One of the most pleasing things over recent weeks is how solid we've been at the back. Today was the same again and it let the forward players go and express themselves.
"It's a team effort from the top of the club to the bottom. The board as well; they stuck by me when we had a bad run.
"The bottom four or five clubs have all lost their managers so credit to the club for having consistency off the pitch in recent times."
St Mirren manager Gary Teale believed the visitors deserved a spot-kick when a perfect Thomas Reilly pass released Jason Naismith before the right-back appeared to be floored by Callum Booth.
The defeat leaves bottom side St Mirren eight points adrift of Motherwell with nine to play for.
"For me we had a stone-wall penalty," Teale told BBC Scotland.
"There are very small margins in this league and these are big decisions. When you're fighting for your life and get calls like that, it's hard to take.
"I think we were a wee bit nervous at the start of the game but we weathered the storm when Thistle were strong.
"I felt we had grown into the game so to come out with a 3-0 defeat is extremely disappointing.
"We'll never give up."