Halliday among 3 leaving Rangers
Andy Halliday, Wes Foderingham and Jon Flanagan are among the players leaving Rangers at the end of their contracts.
Defender Halliday and goalkeeper Foderingham spent five years at Ibrox, helping the club return to the top-flight and reach the Scottish Cup final in 2016.
Former Liverpool defender Flanagan made 39 appearances for Rangers during a two-year spell in Scotland.
Jason Holt, Jordan Rossiter and Jak Alnwick, all on loan during the season, will also depart the club.
Rangers boss Steven Gerrard told the club's official website: "I want to recognise the contribution of the players who are leaving our squad at the end of this season.
"There is a lot more that people contribute to, away from the fixtures each weekend and I commend each of the departing players for what they have given to us day in and day out.
"Work continues on a daily basis in planning and preparation for next season.''
At Kilmarnock, Scotland right-back Stephen O'Donnell has rejected a contract offer and will leave the Rugby Park club at the end of the month.
The 28-year-old turned down the chance to move to Oxford in January and has been linked with the likes of Dundee United in recent weeks.
Eleven-time capped O'Donnell is one of 12 players confirmed to be leaving Killie following the conclusion of the season.
Goalkeeper Laurentiu Branescu and defender Dario Del Fabro, who were signed by previous manager Angelo Alessio, are also departing along with two other shot-stoppers, Jan Koprivec and Devlin Mackay, plus Harry Bunn, Adam Frizzell, Stephen Hendrie, Connor Johnson and Iain Wilson.
Loan players Harvey St Clair and Niko Hamalainen are also departing.
Killie are in talks with Chris Burke, Greg Kiltie, Jamie MacDonald, Rory McKenzie and Ross Millen over new contracts.
Manager Alex Dyer said on Killie's official website: It is never easy to see players depart the club, especially in these circumstances where the guys have not had the chance to say goodbye to the crowd and the fans have not had the opportunity to thank the players for their contribution.
"In Stephen O'Donnell's case, we tried our very best to keep him and spoke on numerous occasions both in person and on the phone but he wants to explore his options as he's entitled to do as a free agent.
"Stephen has been a fantastic player for this football club and a good person to have around the place and as is the case with all the players, we thank them for their efforts and wish them all the very best for the future.''