Her full-length Pure Heroine sold 129,000 copies to debut at number three in the Billboard Top 200 album chart, behind Justin Timberlake's The 20/20 Experience, 2 of 2 and Drake's Nothing Was The Same.
The 16-year-old singer had just delivered a smokey-voiced version of Royals on the US chat show Ellen when her chart placings were announced.
Her performance earned praise from host Ellen Degeneres, who took to the stage to declare her love for the artist.
"Our next guest is only 16 years old and has the number one song in the country. When I was 16 my best friend was a blanket named Tammy," she said.
Degeneres later posted a photo of Lorde's performance to Instagram, with a caption saying she was "incredible".
Watch: Lorde performing Royals on Ellen.
Meanwhile, Lorde has scored a prominent spot on a global Samsung commercial.
Royals
is the soundtrack for Samsung Galaxy ad
The Developer
, which features soccer superstar Lionel Messi.
The commercial's creators were originally going to use a show tune before opting for the hit song, it said.
- nzherald.co.nz