Group B of the 2021 CONCACAF Gold Cup took place from 11 to 18 July 2021 in Frisco's Toyota Stadium and Kansas City's Children's Mercy Park. The group consisted of Canada, Haiti, Martinique, and host nation the United States.
In the quarter-finals:
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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.