Sacking manager Jose Mourinho and his staff in 2015 cost Chelsea £8.3m in compensation, figures released by the Premier League club show.
Mourinho, now in charge of Manchester United, was sacked in December 2015 after a poor start to the Blues’ Premier League title defence.
The club eventually finished 10th, and the financial report for the 2015-16 campaign shows a £70.6m loss.
That includes £67m paid to Adidas to terminate a sponsorship deal early.
The club did that to enter into a more lucrative 15-year deal with Nike, worth an extra £30m a year, BBC Sport reports.
The Adidas contract, which Chelsea ended six years into a 10-year agreement, was worth £30m annually.
Mourinho, 52, had been in his second spell at the club, taking charge in June 2013.
Chelsea finished eight points clear last season and won the League Cup, but lost nine of their 16 league games so far and were 16th in the table, one point above the relegation places.
Mourinho’s final match was a 2-1 defeat at leaders Leicester City.
Chelsea then released a statement: “Chelsea Football Club and Jose Mourinho have today parted company by mutual consent.
“All at Chelsea thank Jose for his immense contribution since he returned as manager in the summer of 2013.
“His three league titles, FA Cup, Community Shield and three League Cup wins over two spells make him the most successful manager in our 110-year history.
“But both Jose and the board agreed results have not been good enough this season and believe it is in the best interests of both parties to go our separate ways.
“The club wishes to make clear Jose leaves us on good terms and will always remain a much-loved, respected and significant figure at Chelsea.
“His legacy at Stamford Bridge and in England has long been guaranteed and he will always be warmly welcomed back to Stamford Bridge.
“The club’s focus is now on ensuring our talented squad reaches its potential.
“There will be no further comment until a new appointment is made.”