Mourinho, who has until 6pm on Friday to respond, was also charged with misconduct last Thursday over comments he made about referee Anthony Taylor in the lead up to the 0-0 draw at Liverpool last month.
Mourinho had until the close of play on Monday to respond to the charge over his Taylor comments.
Press Association Sport understands the disciplinary commission is to rule on the matter before the week is out, but it is the punishment for Saturday's behaviour that may land the hardest blow.
A fine appears the most likely outcome for the Taylor comments, but Mourinho could be hit by a touchline ban following his Old Trafford dismissal.
The United manager is understood to have been sent to the stands as the teams made their way out for the second half. Mourinho was incandescent late in the first half after Matteo Darmian had penalty appeals ignored.
Stoke boss Mark Hughes was only given a fine after being sent to the stands against Tottenham in September, but using abusive and/or insulting language sits in a higher band, with the standard penalty a fine and one-match touchline ban if it is accepted by the manager.
Should Mourinho fail in appealing that charge, though, then it is understood it would increase to a two-match touchline ban.