Swift was the big winner, being awarded Artist of the Year. She also took home Favorite Country album for Red, and Favorite Female Artist in both the Pop/Rock and Country categories.
Timberlake won Favorite Male Artist in the Pop/Rock and Soul/R&B categories, as well as Favorite Soul/R&B album for The 20/20 Experience.
Rihanna won Favorite Female Soul/R&B Artist, but was also presented with the first-ever Icon Award by her mother.
Ariana Grande, who earned a standing ovation from the crowd after her performance, won New Artist of the Year.
Check out a complete list of winners here.