The 2021 Chicago Fire FC season was the club's 23rd year of existence, as well as their 24th in Major League Soccer. This was the Fire's first season with fans in Soldier Field since 2005 (the Fire had officially moved in 2020, however fans were not allowed in Soldier Field due to the pandemic). The Fire would fail to qualify for the playoffs for the fourth season in a row. Head coach Raphael Wicky was ultimately relieved of his position on September 30, with Assistant Coach Frank Klopas taking over on an interim basis.
<small>As of November 1, 2021</small>
<small>Note: Italics indicate the player left the squad or was loaned out and hasn't returned from loan</small>