T. Denny Sanford, a South Dakota banking magnate and philanthropist, died on July 18 at age 90 after donating more than $4 billion over his lifetime. By March, his net worth was estimated at $2.4 billion. Sanford’s donations notably transformed a small regional hospital into one of the largest rural health-care networks in the U.S., bearing his name.
Sanford’s philanthropic efforts spanned decades, with $2 billion going to the Sanford Health system. His contributions also funded the Sanford Underground Research Facility, scholarships such as Build Dakota and Premier/Freedom, and supported organizations like the Sioux Falls Development Foundation and the Children’s Home Society of South Dakota. South Dakota Governor Larry Rhoden called him the state’s greatest philanthropist.
Sanford’s approach to giving was guided by his philosophy of seeking the best return for his community, which he described in a 2007 Forbes interview. His largesse helped foster a strong culture of philanthropy in Sioux Falls and contributed to major community improvements. A 2024 FinancialPlanning study ranked South Dakota as the ninth-most philanthropic state, reflecting Sanford’s impact.
Lt. Governor Tony Venhuizen highlighted Sanford’s role in strengthening philanthropy in Sioux Falls. Sanford’s legacy includes a health-care network, educational scholarships, and scientific research facilities that remain key assets to South Dakota’s community and economy.