That figure includes the likes of Sean Raggett, Louis Thompson and Marcus Harness – as well as current loanees such as Gavin Bazunu and George Hirst.
But the Blues aren’t the only ones currently mulling over their next move when it comes to their soon-to-be out-of-contract players.
Every club in the division has the same predicament, meaning there’ll be a few bargains to be had if agreements with current clubs can’t be thrashed out.
Here, we look at the best players who could potentially be available on frees when the summer transfer window kicks off in June.
1. Elliot Moore - Oxford United
Age: 24; Position: Centre-back; Appearances: 120; Goals: 7; Previous clubs: Leicester Photo: Steve Ellis
2. Chey Dunkley - Sheffield Wednesday
Age: 30; Position: Centre-back; Appearances: 31; Goals: 2; Previous clubs: Wigan, Oxford United. Photo: George Wood
3. Lyndon Gooch - Sunderland
Age: 26; Position: Left-midfield; Appearances: 200; Goals: 24; Previous clubs: Doncaster Photo: Alex Burstow
4. Michael Smith - Rotherham
Age: 30; Position: Striker; Appearances: 198; Goals: 58; Previous clubs: Bury, Northampton, Pompey, Barnsley, Swindon, AFC Wimbledon, Colchester, Newport, Accrington, Charlton Photo: George Wood