The 2020–21 UEFA Champions League qualifying phase and play-off round began on 8 August and ended on 30 September 2020.
In a change to the format as a result of the COVID-19 pandemic in Europe, each tie prior to the play-off round is played as a single-legged match hosted by one of the teams decided by draw, except for the preliminary round which is played at neutral venue.
For any team whose club coefficients are not final at the time of a draw, their club coefficients at that time, taking into account of all 2019–20 UEFA Champions League and Europa League matches played up to that point, are used (Regulations Article 13.03).
If the identity of the winners of the previous round is not known at the time of the draws, the seeding is carried out under the assumption that the team with the higher coefficient of an undecided tie advances to this round, which means if the team with the lower coefficient is to advance, it simply takes the seeding of its opponent.
Prior to the draws, UEFA may form "groups" in accordance with the principles set by the Club Competitions Committee and based on geographical, logistical and political reasons, and they are purely for convenience of the draw and do not resemble any real groupings in the sense of the competition.
[6] The following special rules are applicable to the qualifying phase and play-offs:[7] Four countries (Poland, Hungary, Greece and Cyprus) have provided neutral venue hubs which allow matches to be played at their stadiums without restrictions.
[9] The tournament would originally have started in June 2020, but had been delayed to August due to the COVID-19 pandemic in Europe.
[5] The original schedule of the competition, as planned before the pandemic, was as follows (all draws held at the UEFA headquarters in Nyon, Switzerland, unless stated otherwise).
[12] The final was due to be played at the same venue on 11 August but the match was cancelled due to Drita players being put into quarantine after two players had tested positive for SARS-2 coronavirus, and Linfield were awarded a technical 3–0 win.
[4] For the winner of the preliminary round, whose identity was not known at the time of draw, the club coefficient of the highest-ranked remaining team was used.
The match between KÍ and Slovan Bratislava was cancelled due to Slovan Bratislava players being put into quarantine after one player had tested positive for SARS-2 coronavirus, and KÍ were awarded a technical 3–0 win.
[4] For the winners of the first qualifying round, whose identity was not known at the time of draw, the club coefficient of the highest-ranked remaining team in each tie was used.
From the ten losers of Champions Path, two teams, Tirana and Ludogorets Razgrad, determined by a draw held on 31 August 2020 after the Europa League second qualifying round draw,[3] entered the 2020–21 UEFA Europa League play-off round (Champions Path), while the other eight teams entered the 2020–21 UEFA Europa League third qualifying round (Champions Path).
[4] For the winners of the third qualifying round, whose identity was not known at the time of draw, the club coefficient of the highest-ranked remaining team in each tie was used.