Which UEFA European Championship was the first to feature 24 teams?

UEFA Euro 2016 was the first UEFA European Championship final tournament to feature 24 teams.

The expansion marked a major change from the 16-team format used at Euro 2012 and earlier tournaments since Euro 1996. UEFA had previously staged four-team finals in 1960, eight-team finals from 1980, and 16-team finals beginning in 1996. France hosted the expanded 2016 tournament from 10 June to 10 July.

The 24 finalists were drawn into six groups of four. The top two teams in each group advanced, joined by the four best third-place teams, creating the tournament's first round of 16. That format produced 51 matches rather than the 31 played in a 16-team event.

A common mix-up is confusing the 24-team final tournament with qualifying. Many more than 24 nations entered qualifying; 53 UEFA member associations competed for the final places. Portugal won the tournament, defeating hosts France 1–0 after extra time in the final.