SIOUX FALLS, S.D. (KELO) — South Dakotans are reacting to the death of prominent philanthropist T. Denny Sanford, who died Saturday at the age of 90.

Known also as T. Denny, Sanford was a self-made billionaire who earned his wealth in the banking and subprime credit card industry, with Sioux Falls based First PREMIER Bank and PREMIER Bankcard.  He’s been South Dakota’s wealthiest person for years and also took the “Giving Pledge” with other famous billionaires, such as Bill Gates and Warren Buffet, that he would “die broke.”

“For many years, Mr. Sanford was a champion of our zoo, along with the San Diego Zoo & Safari Park – leading to a one-of-a-kind reciprocity program between our institutions. Mr. Sanford’s generous $25 million donation made it possible for SFZA’s big idea – our merger and pursuit of a one campus land, sea, sky attraction – to begin taking shape. SFZA will be forever grateful for his tremendous support, but we wish he was able to see it all come to fruition.” a post from the Great Plains Zoo said.

“It is with great sadness that Sandy and I mourn the loss of T. Denny – a man who has so generously and intentionally invested in the great state of South Dakota,” Republican Gov. Larry Rhoden said in a news release. “His contributions will not be forgotten, and South Dakota will forever be impacted by his legacy. Put simply, he was the greatest philanthropist in South Dakota history.”

“Denny Sanford was a significant donor to practically every charitable campaign in Sioux Falls, and many others throughout the state. Beyond his high-profile gifts, Denny was a key reason that Sioux Falls has such a strong culture of philanthropy, and many important community improvements benefited from his support,” Lt. Governor Tony Venhuizen wrote on Facebook.

“His generosity and commitment to improving health care have left a lasting impact on South Dakota. His contributions helped expand access to care, advance medical research, and strengthen health services for communities across our state,” the South Dakota Department of Health said on Facebook.

A statement from Sioux Falls Mayor Christine Erickson said “Our community would not be what it is today without T. Denny Sanford’s incredible generosity. Denny’s impact can be seen and felt across the city – from elevated healthcare, to investments in kids and families, to most recently supporting the historic relocation of Smithfield Foods from downtown. His philanthropic spirit encouraged so many others to give, sparking momentum that turned ambitious ideas into real, lasting improvements. He will be deeply missed, and the culture of generosity he helped build will continue to shape generations to come.”

A news release Saturday morning announced Sanford’s passing. Prominent South Dakotans are sharing their reactions and words about the businessman.

“Denny changed the landscape of giving. He could have done many things with his money, yet he reinvested it in South Dakota. Our universities are stronger today because of Denny. Our health care is stronger today because of Denny. He believed in working harder to help someone other than yourself,” Miles Beacom, the CEO of PREMIER Bankcard, said in a news release.

“Denny’s passion for helping people and inspiring others to do the same is unmatched. From the first day I met him, I understood how important that was to him. He often said many people live a life of success, but you should try to live a life of significance where you can make an impact on people,” said Dana Dykhouse the CEO of First PREMIER Bank.

“We are forever blessed that Denny chose us and our communities to make the transformational gifts that will change lives for generations. He was a driving force in modern medicine, empowering researchers and clinicians to think big and pursue bold, innovative endeavors at a pace not otherwise possible. We are able to provide care for more patients in their time of need because of his generosity,” Bill Gassen, President and CEO, Sanford Health said in a news release.

A joint statement from First PREMIER Bank and PREMIER Bankcard & Sanford Health said “We are saddened to announce the passing of T. Denny Sanford. He was 90 years old. Denny always said he wanted to live a life of significance and gave generously. His philanthropy impacted millions of lives and transformed the landscape of South Dakota and beyond.”

“During my years as mayor, I had the privilege of witnessing firsthand the extraordinary impact of T. Denny Sanford’s generosity. His love for South Dakota was evident in the countless lives he changed and the bold visions he helped bring to life. His legacy will endure for generations,” Former Sioux Falls mayor Paul TenHaken said in a post on X.

“Denny Sanford’s generosity will leave a lasting legacy on Sioux Falls,” said Andy Patterson, CEO of the Community Foundation on social media. “He modeled philanthropy in a way that brought others along with him – a kind of giving that begets more giving, which has shaped our community in ways that will matter for generations. We offer our deepest gratitude for his thoughtfulness and our condolences to his family and friends.”

“”I’m sorry to hear about the passing of Denny Sanford. His philanthropy touched countless lives through investments in healthcare, education, and children’s well-being, leaving a lasting impact on communities across our state and beyond. My thoughts are with his family, friends, and all those whose lives were shaped by his generosity. May they find comfort in the many lives he helped improve and the legacy he leaves behind,” Dan Ahlers, Democrat candidate for governor said in a statement.

“Saddened to hear of the passing of Denny Sanford. Denny was a giant in South Dakota who was constantly working to make our state a better place through philanthropy. Specifically, he gave his money to causes that will help the next generation of South Dakotans prosper, including health care, science and education.” U.S. Senator Mike Rounds said in a post on X.

The University of Sioux Falls issued a statement, saying: “At our university, the impact of Mr. Sanford’s gifts stretch from the Sanford School of Medicine to the Knudson School of Law and from the National Music Museum to the future Gassen Family Fieldhouse. He opened doors for students through scholarship support and maintained a firm belief in the transformational power of education.”

You can read the full obituary below.

This is a developing story.