The Manhattan art adviser Lisa Schiff, who admitted to stealing millions of dollars clients gave her to buy art, but which she instead burned through to fund her life of luxury, was sentenced to two and a half years in federal prison on Wednesday.

U.S. District Judge J. Paul Oetken sentenced Ms. Schiff, 55, to 30 months in prison, followed by two years supervised release for perpetrating a scheme in which she stole about $6.5 million from over a dozen clients, many of whom she had cultivated into close personal friends. The fraud, in which Ms. Schiff would either make off with money clients entrusted her with (to buy them art), or siphon off proceeds of the sales of their collections that she helped facilitate, began in 2018 and came to involve some 55 artworks. In 2023, after clients confronted her, Ms. Schiff turned herself in to the authorities. She pleaded guilty to one count of wire fraud in October.

As the scheme played out, Ms. Schiff lived a jet-setting life alongside her clients, who said in court documents that they had no idea it was their money she was spending as she traveled with them on the art fair circuit, lavishing it on the likes of shopping sprees and chartered helicopters. The revelations surrounding Ms. Schiff shook the art world, in which she had risen to prominence as a one time adviser to Leonardo DiCaprio, and where she positioned herself as an ethical authority in the largely unregulated business of art advising, or guiding wealthy collectors on what works to buy.

“For five years, Lisa Schiff breached the trust of her art advisory clients by diverting millions of dollars to pay her own business and personal expenses, and to fund a lavish lifestyle,” the Acting U.S. attorney, Matthew Podolsky, said in a statement on Wednesday. “Because of Schiff’s lies, and her illusory art advisory scam, Schiff will now serve a substantial sentence in prison.”

Reached by text message, Ms. Schiff, who has been living in Stuyvesant Town in Manhattan with her 12-year-old son as she awaited sentencing, declined to comment and responded to this reporter’s inquiry with “no comment” and a heart emoji.

In a previous interview with The New York Times, her first since pleading guilty, Ms. Schiff said she had been suffering from addiction issues at the time. She expressed remorse for her actions, particularly as they related to her child, whom she raises alone. In the interview, she said her son will be cared for by her brother while she serves her sentence. “I feel so guilty to my victims, so guilty,” she said at the time. “But I am shocked that I didn’t think through what I was potentially doing to my son,” Ms. Schiff added.

“This has been an emotional, trying and difficult time for everyone,” her lawyer, Randy Zelin, said in an email. “Everyone with skin in this has been affected.” He added: “We are going to work now to position Lisa to succeed while she is in custody, to get her healed and home as quickly as we can.”

Wendy J. Lindstrom, a lawyer who represents seven of the people suing her, including the real estate heiress and prominent art collector Candace Barasch, who considered Ms. Schiff a close friend, and who has since filed lawsuits claiming her longtime adviser stole millions from her, had not responded to a request for comment as of the time of publication.

Ms. Schiff has declared bankruptcy and her personal art collection is being auctioned off to repay her clients. As part of her sentencing, the court ordered Ms. Schiff to forfeit more than $6.4 million, and restitution of over $9 million to the people she robbed.