The singer also won pop artist of the year and favorite tour style.
Both tracks are included on Timberlake's 'Everything I Thought It Was.'
SZA accepted multiple awards onstage Monday night, including song of the year.
The star-studded event is set to take over Los Angeles' Dolby Theatre on April 1.
Additionally, it was revealed that Ludacris will be hosting and performing at the event.
The pair met up backstage at the awards show, which the 'Mama Said' singer hosted.
Here are photos of the stars who attended the 2023 iHeartRadio Music Awards, from the red carpet to backstage and beyond.
"Taylor has always told the truth," Phoebe Bridgers said while introducing her collaborator & soon-to-be tourmate.
The ceremony will feature 9 performances, including one from host Lenny Kravitz.
P!nk will receive the 2023 iHeartRadio Icon Award. She'll also perform on the show.
