Billie Eilish has a new tattoo, but is keeping its location a secret.

The 18-year-old Grammy winner took part in the fourth instalment of her annual video interview with Vanity Fair, and revealed that she had finally crossed one item off her bucket list during 2020.

“I did get a tattoo. But you won’t ever see it," Billie teased.

The Bad Guy hitmaker is notoriously private about her personal life, preferring to keep her body hidden under baggy clothes to avoid being body shamed.

She also touched upon the paparazzi photo of herself that went viral in October, which showed her wearing a tight vest top and shorts while visiting her older brother Finneas O'Connell in Los Angeles.

"There’s this picture of me running from my car to my brother’s front door on like a 110 degree day in a tank top. And people were like, ‘Damn, Billie got fat!' And I’m like, ‘Nope, this is how I look, you’ve just never seen it before!" she explained. "But, whatever."

Billie was later asked if she thought her "messaging on body image has had a positive effect" and she confessed she loves being responsible for her younger fans having more body confidence.

"I love having kids relate to me and tell me that I make them feel comfortable in their bodies," the singer shared. "If I can do anything, I want to do that."