Despacito was a huge hit in 2017 and Vevo has revealed the music video to go with it was just as big.
The music video platform says Despacito was watched 4.3 billion times globally and 64.7 million times in the UK.
The reggaeton-pop tune by Luis Fonsi, featuring Daddy Yankee, was number one in 47 countries.
Vevo says it was the most watched video of 2017 in the UK, followed by French Montana's Unforgettable which had 56.7 million views.
The top five videos watched around the world are all Reggaeton or reggaeton/pop tracks.
Although Despacito was the most watched video in the UK, over in the US it was beaten by Post Malone's Congratulations.
Taylor Swift was the most watched artist in the US.
Ed Sheeran takes Shazam
Meanwhile, Ed Sheeran's former 12-week number one hit on the Billboard Hot 100, Shape of You, is the most Shazamed song of 2017.
The track logged over 15 million Shazams on the song-tagging app this year.
Sheeran, who also earns the title as "Most Shazamed Artist of the Year," succeeds Sia's Cheap Thrills, which logged the most tags in 2016.