Sevilla defeated Inter Milan in the final, played at the RheinEnergieStadion in Cologne, Germany, 3–2 for a record-extending sixth title in the competition.

The quarter-finals onwards were played as a single match knockout ties at neutral venues in Germany (RheinEnergieStadion, MSV-Arena, Merkur Spiel-Arena, Arena AufSchalke) behind closed doors from 10 to 21 August.

[3] The video assistant referee (VAR) system was used in the competition from the knockout stage onwards.

They were unable to defend their title as they advanced to the Champions League knockout stage, and were eliminated by the ultimate winners Bayern Munich in the round of 16.

[7] Apart from the allocation based on the country coefficients, associations could have additional teams participating in the Champions League, as noted below: The following is the access list for this season.

In any case where a spot in the Europa League was vacated, cup winners of the highest-ranked associations in earlier rounds were promoted accordingly.

When a place was vacated, it was redistributed within the national association by the following rules: The labels in the parentheses show how each team qualified for the place of its starting round:[8] One team not playing a national top division took part in the competition; Vaduz (representing Liechtenstein) played in 2019–20 Swiss Challenge League, which is Switzerland's 2nd tier.

The schedule of the competition was as follows (all draws were held at the UEFA headquarters in Nyon, Switzerland, unless stated otherwise).

[23] On 17 June 2020, UEFA announced the revised schedule for the quarter-finals, semi-finals and final of the competition, to be played in single-leg matches.

Due to the varying rates of transmission of COVID-19 across European countries during the time of the Round of 16 first leg ties, different matches were affected in different ways.

On 15 March, UEFA announced that none of the Round of 16 second leg ties would go ahead in the following week, postponing them indefinitely,[26] with a taskforce convened to reschedule the rest of the season.

The draw for the group stage was held on 30 August 2019, 13:00 CEST, at the Grimaldi Forum in Monaco.

The mechanism of the draws for each round was as follows: On 17 June 2020, UEFA announced that due to the COVID-19 pandemic in Europe, the final stages of the competition would feature a format change.

The quarter-finals, semi-finals, and final would be played in a single-leg format from 10 to 21 August 2020 in the German cities of Cologne, Düsseldorf, Duisburg and Gelsenkirchen.

The matches were tentatively played behind closed doors, though spectators could be allowed subject to a review of the situation and the decisions of the national and local government.

[48] The award winner was announced during the 2020–21 UEFA Europa League group stage draw in Switzerland on 2 October 2020.