The knockout stage of the 2021 CONCACAF Gold Cup began on 24 July 2021 with the quarter-finals and ended on 1 August 2021 with the final at the Allegiant Stadium in Paradise.
All match times listed are EDT (), as listed by CONCACAF. The local time is also given.
In the knockout stage, if a match was level at the end of 90 minutes of normal playing time, extra time was played (two periods of 15 minutes each), where each team was allowed to make a sixth substitution. If still tied after extra time, the match was decided by a penalty shoot-out to determine the winners.
The top two placed teams from each of the four groups qualified for the knockout stage.
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