The Portuguese boss was dismissed in December after two-and-a-half years in charge at Old Trafford following a wretched run of form.
In the club’s half-yearly results published on Thursday, United list £19.6 million under ‘exceptional items’ for "compensation to the former manager and certain members of the coaching staff for loss of office".
Mourinho was sacked along with six members of his coaching team and replaced with caretaker boss Ole Gunnar Solskjaer, who led the team to 10 wins in his first 11 games before suffering defeat against Paris Saint-Germain in the Champions League last 16 on Tuesday.
Executive vice-chair Ed Woodward declared his delighted with the impact of his new coaching team.
“The appointment of Ole and Mike (Phelan) as caretaker manager and assistant manager, working with Kieran [McKenna], Michael [Carrick] and Emilio [Alvarez], has had a positive impact throughout the club,” he said.
“We're delighted with the improvement in the team’s performances since December and we look forward to a strong finish to the 18/19 season.”
Despite the expense of Mourinho’s sacking, United posted record revenues in the final three months of 2018, with total incomings of £208.6 million.
