Host country Italy was selected among the four qualified teams by the UEFA Executive Committee, with the winners of the final crowned as the Nations League champions.

The team that scored more goals on aggregate over the two legs remained in League C, while the loser was relegated to League D. If the aggregate score was level, extra time was played (the away goals rule was not applied).

[2] The overall UEFA Nations League rankings were established as follows:[2] The Nations League was partially linked with European qualification for the 2022 FIFA World Cup in Qatar, with the format confirmed by the UEFA Executive Committee during their meeting in Nyon, Switzerland on 4 December 2019.

On 31 March 2021, the use of five substitutes was extended to the Nations League Finals in October 2021 and the League C relegation play-outs in March 2022, with these knockout matches permitting a sixth substitution should the match go to extra time.

[15] All matches played in September 2020 were required by UEFA to be held behind closed doors due to the COVID-19 pandemic in Europe.

However, the return of spectators was subject to the decision of local authorities, with regional limits taking precedence over UEFA's maximum allowed capacity.

Social distancing was mandatory for spectators and additional precautionary measures (such as face masks) were implemented per local regulations.

[20][21][15] The scheduling of the league phase was reviewed by the UEFA Executive Committee during their meeting on 17 June 2020.

[23] This allowed for the UEFA Euro 2020 qualifying play-offs, along with the postponed March 2020 international friendlies, to be played on 7–8 October and 11–12 November 2020.

[24] The changes to the International Match Calendar for October and November 2020, which extended each window by one day, were approved by the FIFA Council on 25 June 2020.

[26] However, due to the change of the league phase calendar, a revised schedule for the October and November 2020 fixtures was released by UEFA on 26 June 2020.

[27][28] The relegation play-outs of League C were scheduled on the same dates as the 2022 FIFA World Cup qualifying play-offs.

[10][30] The draw for the league phase took place at the Beurs van Berlage Conference Centre in Amsterdam, Netherlands on 3 March 2020, 18:00 CET.

[35] The semi-final pairings were determined by means of an open draw on 3 December 2020, 17:30 CET, at the UEFA headquarters in Nyon, Switzerland.