The tournament consisted of two semi-finals, a third place play-off, and final to determine the inaugural champions of the UEFA Nations League.

Portugal won the final 1–0 against the Netherlands to become the inaugural champions of the UEFA Nations League.

The semi-final pairings, along with the administrative home teams for the third place play-off and final, were determined by means of an open draw on 3 December 2018.

[9] On 3 December, UEFA confirmed that the video assistant referee (VAR) system would be used for the Nations League Finals.

[11] Portugal was confirmed as the host country by the UEFA Executive Committee during their meeting on 3 December 2018 in Dublin, Ireland.

[14][15] On 9 March 2018, UEFA announced that Italy, Poland, and Portugal expressed interest in bidding prior to the deadline.

[2] The draw took place on 3 December 2018, 14:30 CET (13:30 local time), at the Shelbourne Hotel in Dublin, Ireland.

[5] Each national team had to submit a squad of 23 players, three of whom had to be goalkeepers, at least ten days before the opening match of the tournament.

[35] UEFA also announced a team of the tournament based on the FedEx Performance Zone player rankings.

In addition, the participants received payment based on performance: This meant that the maximum amount of solidarity and bonus fees for the UEFA Nations League winners was €10.5 million.