Martha Stewart used to earn $65 million a year from a brand deal, but she lost $1 billion when she fell into tough times.

The 85-year-old lifestyle guru was previously in partnership with department store chain Kmart – and it made her a fortune in royalties.

Speaking on the trailer for the first episode of Masterclass podcast Other People’s Business, she says of the partnership: “I was clearing $US65 million ($A93 million) a year in royalties.”

Elsewhere, Stewart revealed she once lost $US1 billion ($A1.4 billion) during a difficult stage of her life.

“I fell in a hole, and I lost about $US1 billion ($A1.4 billion),” she said.

Stewart served five months in prison from October 2004 to March 2005 after she was found guilty of conspiracy, obstruction of justice, and making false statements to federal investigators regarding her sale of ImClone Systems stock.

She hasn’t ever spent any money on plastic surgery, insisting she has avoided going under the knife for facial enhancements.

But she does get fillers to help maintain her youthful look.

Speaking in August, Stewart told PEOPLE: “I go to Dr Dan Belkin in New York City. He is a very superb dermatologist. And I use a little bit of fillers. I go maybe once every four months for touch-ups.

“I have not had any plastic surgery at all. I don’t think I need it.”

Stewart has ruled out having body enhancements, saying: “I’m not getting boobs done and hips and butts and stuff like that.”

Martha appeared on the cover of the Sports Illustrated Swimsuit Issue in 2023, aged 81.