Renowned philanthropist and businessman T. Denny Sanford passed away July 18, 2026 in his hometown of Sioux Falls, South Dakota. He was 90 years old.
Renowned philanthropist and businessman T. Denny Sanford passed away July 18, 2026 in his hometown of Sioux Falls, South Dakota. He was 90 years old.
A self-made billionaire, Sanford had spent recent decades diligently spreading that wealth through philanthropy, primarily focusing on education, health services and biomedical research. His motto: “Aspire to inspire before you expire.”
“Denny was larger than life. He loved people, philanthropy, business and golf. He was my supporter and advisor, but more importantly, my confidant and friend. Denny was fascinated by science and education, especially in advancing ideas and efforts that would make lives better, both in terms of health and in well-being,” said David Brenner, CEO and president of Sanford Burnham Prebys Medical Discovery Institute.
“His generosity was manifest, from supporting research and treatment of rare children’s diseases to stem cells to recruiting new generations of bright, young scientists to carry on the work. He loved to hear about how his philanthropic investments have benefited young people.”
Sanford Burnham Prebys was a frequent beneficiary. In 2007, for example, Sanford gave the institute $20 million through Sanford Health, the largest rural health system in the U.S. and a longtime beneficiary of Sanford. The gift helped the then-called Burnham Institute to create the Sanford Children’s Health Research Center. A year later, Sanford donated $30 million to create the Sanford Consortium for Regenerative Medicine, with the Institute as a founding member.
Two years later, Sanford donated $50 million and The Burnham Institute became the Sanford-Burnham Medical Research Institute. In 2023, he gave $70 million to Sanford Burnham Prebys to launch an ambitious plan to recruit up to 20 new scientists.
Sanford has been an honorary trustee at Sanford Burnham Prebys since 2010.
“Long before Denny’s and my names became inextricably linked through the Sanford Burnham Prebys Medical Discovery Institute, we shared a common goal to make an impact in our communities and to serve others,” said Malin Burnham, who has served on its board of directors since 1982. “Denny embodied that purpose throughout his life, generously investing himself and his resources to benefit others, often with truly transformational results.”
“Denny’s commitment to health and medicine was extraordinarily broad and deep,” noted Donald Kearns, MD, chair of the Board of Directors at Sanford Burnham Prebys and president emeritus of Rady Children’s Hospital-San Diego. Indeed he partnered with and supported specialized pediatric care for local families through the hospital, Sanford Children’s Clinic in Oceanside and the Children’s Primary Care Medical Group.
Sanford fundamentally believed that basic research and the benefits derived were driven and sustained by the people who do it. That was most evident in his philanthropy supporting education and in supporting new generations of scientists, said Brenner.
“Denny was a visionary committed to making a better world. His $70 million gift to recruit new faculty—the young investigators who will be future leaders—was a transformational investment in the continued strength of biomedical research at Sanford Burnham Prebys and across the Torrey Pines Mesa.,” said Brenner.
Sanford was born in Saint Paul, Minn. in 1935 during the Great Depression. His mother died of breast cancer when he was four years old. “She had been in the hospital for about a year before she died, so I have no memory of her at all,” Sanford recalled, but her death would inspire significant, subsequent support of cancer research by her son.
His father passed when he was 20.
“We have a lot of heart disease in my family,” he told the Horatio Alger Association, which honored him in 2016. “My father had several heart attacks throughout my childhood. My older brother had a fatal heart attack at the age of 40. I also had a heart attack at the age of 44, but I have had good health since then. But the loss of my father when I was still so young was a major blow to me.
“He was the most caring person I ever met. He never graduated high school because he had to help support his family. He was very giving, and I think my ideas about philanthropy, which is such an important part of my life today, came from him.”
Sanford did graduate from high school—and the University of Minnesota in 1959. In the following years, Sanford would be a sales representative for industrial cork and building materials. He started a distribution company that he transformed into a manufacturing and research firm.
In 1986, he purchased a small bank in Sioux Falls, South Dakota with $80 million in assets, then created a credit card business: United National Corp., with its two subsidiaries, First Premier Bank and Premier Bankcard, soon had a $1 billion portfolio of credit card loans.
The scope of Sanford’s philanthropy is staggering.
He has donated more than $1 billion to Sanford Health, a system of 48 medical centers, 211 clinics and 160 senior living centers in the upper Midwest, California and Florida, including funding to establish the Edith Sanford Breast Center in honor of his mother.
“What we always said is that at the end of every single decision we make is a patient,” said Bill Gassen, president and CEO of Sanford Health. “And for Denny, at the end of every gift is a patient.”
In addition, Sanford has made multi-million dollar gifts to the Sanford Underground Research Facility, the Sioux Falls Development Foundation, the Sioux Falls Zoo and Aquarium and the Children’s Home Society of South Dakota.
A part-time resident of San Diego, Sanford has made similar and substantial gifts to a host of local institutions: UC San Diego, National University, the Salk Institute, San Diego Public Library and the Zoological Society of San Diego.
To date, it’s estimated Sanford’s total philanthropy is approximately $2 billion.
“We are on earth to provide for other people, not just ourselves and our families,” Sanford said before his induction into South Dakota’s Hall of Fame in 2007. “We all have the opportunity to work a little bit harder and help someone else, not just ourselves.”