Brant was raised in Jamaica Estates, Queens, the son of Lily and Murray Brant. Brant's father – who emigrated from a small town near the border of Romania and Bulgaria – co-founded the paper converter (primarily converting paper into newsprint) Brant-Allen Industries with his cousin H. Joseph Allen. He has one sister, Irene Brant Zelinsky and was a childhood friend of Donald Trump. Brant attended the University of Colorado but did not graduate instead leaving to work for his father's company.
Brant went to work at Brant-Allen Industries, a paper conversion company co-founded by his father, Murray Brant. In the early 1970s, Brant and a cousin, Joseph Allen — the son of Murray Brant’s business partner — led the company into the manufacturing side of the business and expanded the company into paper mill (converting pulp into paper) ownership purchasing a mill in Rivière-du-Loup, Quebec and partnering with the Washington Post and Dow Jones to purchase a mill in Ashland, Virginia. In the early 2000s, as paper demand continued to decline, Brant embarked on a buying spree purchasing a second Quebec mill in 2004 for $205 million (from Enron) and a third Quebec mill in 2006 for $135 million. In 2008, he bought out his partner and changed the name of the company to White Birch Paper Company. Also in 2008, he purchased SP Newsprint Co for $305 million, a newsprint manufacturer with operations in Oregon and Georgia. The purchase gave Brant control of 22% of the North American newsprint market, second to AbitibiBowater with 43%. Brant expanded SP Newsprint into paper recycling operating 23 recycling facilities through its SP Recycling unit.
In 2007, Brant deflected any talk of an imminent bankruptcy and seemed unbowed and upbeat for a man who said he personally has lost $1 billion in the span of two years. In a court filing around that time, he said the ailing newsprint market and the recession had slashed his net worth to less than $500 million from $1.4 billion that year.
In February 2010, White Birch Paper restructured under Chapter 11 proceedings, due to excessive debt and declining demand for newsprint. The company emerged from bankruptcy in January 2012 and closed its main pulp and paper mill in Quebec City, sending home more than 600 workers. White Birch owns two other mills in Quebec, Canada and one in Ashland, Virginia. In 2012, Brant pledged a portion of his art collection as security to purchase White Birch Paper out of bankruptcy in partnership with Black Diamond Capital Management LLC for $94.5 million in cash and $78 million in debt. Brant remains as CEO of White Birch Paper.
In November 2011, SP Newsprint Co filed for Chapter 11 bankruptcy due to excessive debt and declining demand for newsprint. SP Newsprint operates two mills in Dublin, Georgia and Newberg, Oregon and 23 recycling facilities. In September 2012, SP Newsprint was purchased out of bankruptcy by SP Fiber Technologies LLC for an undisclosed amount.
In May 2016, the one-time billionaire merged the magazines Art in America with its principal competitor ARTnews. Artnet News reported his company announced the ARTnews would go to a quarterly publication schedule, down from monthly. The latter had run an article asking whether the Brant Foundation was a tax scam or an art investment vehicle.
In May 2017, White Birch Paper announced that it would idle paper making operations at its Bear Island newsprint mill in Ashland, Virginia. The Bear Island mill produced 240,000 metric tons of newsprint annually.
Brant is the owner and chairman of Brant Publications, Inc., located in New York City, founded in 1984. BPI publishes four magazines:Interview was founded by artist Andy Warhol and John Wilcock in late 1969. These interviews were usually unedited or edited in the eccentric fashion of Warhol's books and The Philosophy of Andy Warhol: From A to B and Back Again. Brant Publications began publishing Interview shortly after Warhol’s death in 1987. The magazine celebrated its 40th anniversary in 2010.
The magazine Antiques is a monthly arts publication that focuses on architecture, interior design, and fine and decorative arts. Regular monthly columns include news on current exhibitions and art-world events, notes on collecting, and book reviews. The magazine was founded in 1922 and underwent a complete redesign in 2009.
Art in America is an illustrated monthly, international magazine concentrating on the contemporary art world. It has been published since 1913.
Modern, was launched in 2009 and is a magazine devoted to design, decorative arts and architecture.
Brant’s interest in art also led him into film production. He was a producer of L’Amour in 1973 and Andy Warhol's Bad in 1977. Brant was an executive producer of the award-winning films Basquiat (1996) and Pollock (2000). Brant was also co-producer of the Peabody- and Emmy-award winning PBS documentary, Andy Warhol: A Documentary (2006). Brant is a producer of The Homesman, an 1850s period Western and official selection for the 2014 Cannes Film Festival, directed by and starring Tommy Lee Jones, Hilary Swank and Meryl Streep.
Brant bought his first pieces of art after turning an $8,000 investment into several hundred thousand dollars as a young man. His first purchases according to The New York Times, included "a couple of Warhols and, later, a major Franz Kline.” In 1976, Brant commissioned Andy Warhol to paint his cocker spaniel, Ginger. Warhol made two paintings of Ginger, as well as drawings.
On May 9, 2009, The Brant Foundation Art Study Center opened in Greenwich, CT. On the site of a converted 110-year-old stone barn, architect Richard Gluckman redesigned the 9,800-square-foot (910 m2) space as a gallery and learning center, which will showcase long-term exhibitions and promote the appreciation of contemporary art and design. The non-profit center is open to the public by appointment.The Brant Foundation Art Study Center featured an exhibition by artist Urs Fischer in 2010 and painter Josh Smith in 2011. Brant's tax returns for 2010 showed that he contributed $3 million to the foundation, and it spent $1.8 million on acquisitions, exhibitions and building-related costs. In 2016, the museum was scrutinized as a tax evasion strategy that allowed Brant to benefit from a tax write off while providing limited public benefit.
After the artist Walter De Maria died in 2013, Brant bought his Manhattan studio, a former Con Edison substation at 421 East Sixth Street, as an exhibition space for $27 million.
Brant is a member of the Advisory Council of the Andy Warhol Museum in Pittsburgh. The Museum of Contemporary Art (MOCA) in Los Angeles named Brant to its Board of Trustees in December 2009.
Brant was a member of the partnership who owned Classic winner Swale, who won both the 1984 Kentucky Derby and Belmont Stakes and was champion three-year-old that year. In addition, Brant was responsible for bringing legendary stallion Mr. Prospector to Claiborne Farm in Paris, KY. Mr. Prospector, who began his stud career in Florida in 1975 went on to be one of the most influential sires in the American Stud-Book since his first runners hit the races in 1978. Brant was the breeder of 1995 Kentucky Derby winner Thunder Gulch. Thunder Gulch is the son of Gulch out of the mare Line of Thunder, who were both owned and bred by Brant. In addition, Brant is an accomplished polo player and at one time, was the highest-rated amateur player in the U.S. Brant is the co-founder of the Greenwich Polo Club, the Saratoga Polo Association, and the Bridgehampton Polo Club.
Brant has five children from his first marriage to Sandra Simms (born 1955); she later married writer Ingrid Sischy Four of his children with Simms have worked for Brant companies: Christopher as president of White Birch; Ryan as director of Brant Publications, Kelly as online director Brant Publications; and Allison as director of the Brant Foundation. They divorced in 1995. On July 14, 1995, Brant married supermodel Stephanie Seymour (born 1968) and they have two sons and one daughter together: Peter Brant, Jr. (born December 1993), Harry (born 1996), and Lily (born October 27, 2004). In 2009, the couple filed for divorce but subsequently reconciled. He has a stepson, Dylan, from Seymour's first marriage to guitarist Tom Andrews and ten grandchildren.
In 1990 Brant was investigated for tax evasion resulting from reportedly having his company pay for $1 million in personal expenditures. Brant pled guilty to charges of failing to keep records and was sentenced to three months in a federal prison and $200,000 in fines.