Following a format change from the first season, League A was expanded from 12 to 16 teams. The league consists of the top ranked UEFA members from 1–16 in the 2018–19 UEFA Nations League overall ranking, split into four groups of four. Each team will play six matches within their group, using the home-and-away round-robin format on double matchdays in September, October and November 2020. The winners of each group will advance to the 2021 UEFA Nations League Finals, and the fourth-placed team of each group will be relegated to the 2022–23 UEFA Nations League B. The Nations League Finals will be played in a knockout format, consisting of the semi-finals, third place play-off, and final. The semi-final pairings will be determined by means of an open draw. The host country will be selected among the four qualified teams by the UEFA Executive Committee, with the winners of the final crowned as the champions of the UEFA Nations League. Though originally planned for 2–6 June 2021, the Nations League Finals will be moved to September or October 2021 following the rescheduling of UEFA Euro 2020 to June and July 2021 due to the COVID-19 pandemic. The four group winners will be drawn into groups of five teams for 2022 FIFA World Cup qualification.
Teams
Team changes
The following are the team changes of League A from the 2018–19 season:
The following team changes were initially set to occur in League A, but did not after no teams were relegated due to the format change by UEFA:
Initially relegated to Nations League B
Seeding
In the 2020–21 access list, UEFA ranked teams based on the 2018–19 Nations League overall ranking, with a slight modification: teams that were originally relegated in the previous season were ranked immediately below teams promoted prior to the format change. The seeding pots for the league phase were confirmed 4 December 2019, and were based on the access list ranking.
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. Each group contains one team from each pot.
Groups
The original fixture list was confirmed by UEFA on 3 March 2020 following the draw. On 17 June 2020, the UEFA Executive Committee adjusted the league phase schedule for October and November 2020 to allow for the completion of the UEFA Euro 2020 qualifying play-offs. Following the change, a revised schedule for the October and November 2020 fixtures was released by UEFA on 26 June 2020. Times are CET/CEST, as listed by UEFA.
Group 1
---- ---- ---- ---- ----
Group 2
---- ---- ---- ---- ----
Group 3
---- ---- ---- ---- ----
Group 4
---- ---- ---- ---- ----
Nations League Finals
The host of the Nations League Finals will be selected from the four qualified teams. The semi-finals pairings will be determined by means of an open draw. For scheduling purposes, the host team is allocated to semi-final 1 as the administrative home team.
Bracket
Semi-finals
----
Third place play-off
Final
Overall ranking
The 16 League A teams will be ranked 1st to 16th overall in the 2020–21 UEFA Nations League according to the following rules:
The teams finishing first in the groups will be ranked 1st to 4th according to the results of the Nations League Finals.
The teams finishing second in the groups will be ranked 5th to 8th according to the results of the league phase.
The teams finishing third in the groups will be ranked 9th to 12th according to the results of the league phase.
The teams finishing fourth in the groups will be ranked 13th to 16th according to the results of the league phase.
