2021 Atlanta United FC season

The 2021 Atlanta United FC season was the fifth season of Atlanta United FC's existence, and the thirteenth year that a professional soccer club from Atlanta, Georgia competing in the top division of American soccer. Atlanta United played their home games at Mercedes-Benz Stadium. Due to the cancelation of the 2020 U.S. Open Cup, Atlanta competed in the 2021 CONCACAF Champions League as the final berth was given to the defending champions of the U.S. Open Cup.

International roster slots
Atlanta currently has ten International Roster Slots for use in the 2021 season. Matheus Rossetto obtained a green card in April 2021 to qualify as a domestic player for MLS roster purposes.

Appearances and goals
! colspan=16 style=background:#dcdcdc; text-align:center|Goalkeepers

! colspan=16 style=background:#dcdcdc; text-align:center|Defenders

! colspan=16 style=background:#dcdcdc; text-align:center|Midfielders

! colspan=16 style=background:#dcdcdc; text-align:center|Forwards

! colspan=16 style=background:#dcdcdc; text-align:center|Players who have played for Atlanta United this season but have left the club:


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SuperDraft picks
Draft picks are not automatically signed to the team roster. Only trades involving draft picks and executed after the start of 2021 MLS SuperDraft are listed in the notes. Atlanta have three selections in the draft.