The Shake It Off singer and Sam Smith both scored four nominations in the first five categories, which were announced by rapper Ludacris and rocker Pete Wentz on U.S. morning show Good Morning America - and then Swift went on a streak, landing another 10 nods.

Swift and Smith both earned nods for Top Artist, Top Billboard 200 Album Artist and Top Hot 100 Song, while Swift will also compete for the Top Female Artist title, Top Digital Songs Artist, Top Radio Songs Artist and Top Social Artist, among other categories.

Smith fell one short of his pal's nominations haul with 13, while Iggy Azalea picked up 12 nods and Meghan Trainor scored nine.

The 2015 Billboard Music Awards will take place on 17 May (15) at the MGM Grand Garden Arena in Las Vegas.

Ludacris and Chrissy Teigen will co-host.