Costa was originally handed a two-match ban, but will now miss three games.
The first of those was the 2-2 draw with West Ham on 19 March and he is suspended for Saturday’s away game at bottom-placed Aston Villa.
Costa, who has also been warned as to his future conduct, will now be absent for his side’s trip to Swansea on 9 April.
Everton won the FA Cup quarter-final 2-0 at Goodison Park and Costa was sent off in the 84th minute for two bookable offences – the first on-pitch red card of his Chelsea career.
However, he originally received a two-game automatic ban as it was considered to be his second dismissal of the season after he was given a retrospective three-match ban for altercations with Arsenal’s Laurent Koscielny and Gabriel in September.
Costa helped Chelsea win the Premier League title last season and has scored 11 goals in his past 16 games under manager Guus Hiddink.
On Friday, the Dutchman said he would use the final eight games of the Premier League season to “experiment”, with the club 10th in the table.