Group A of the 2021 CONCACAF Gold Cup took place from 10 to 18 July 2021 in Arlington's AT&T Stadium, Dallas' Cotton Bowl and Frisco's Toyota Stadium. The group consisted of El Salvador, Guatemala, defending champions Mexico, and Trinidad and Tobago.
Originally, Curaçao would have played in this group. On 9 July 2021, Curaçao was removed as a participant due to close contacts with those tested positive to COVID-19 and replaced by Guatemala.
In the quarter-finals:
<section begin=A2 /><section end=A2 />
<section begin=A1 /><section end=A1 />
<section begin=A3 /><section end=A3 />
<section begin=A4 /><section end=A4 />
<section begin=A5 /><section end=A5 />
<section begin=A6 /><section end=A6 />
Fair play points would have been used as a tiebreaker should the overall and head-to-head records of teams were tied. These were calculated based on yellow and red cards received in all group matches as follows:
Only one of the above deductions was applied to a player in a single match.