Thomas 'Denny' Sanford, a prominent philanthropist and influential figure in South Dakota, peacefully passed away on July 18, 2026, at the age of 90. Born on December 23, 1935, in St. Paul, Minnesota, Denny dedicated his life to philanthropy, impacting millions through his generous contributions.

Denny's early life was marked by personal tragedy; he lost his mother to breast cancer at the age of four, which instilled in him a deep desire to help others. He began working at his father's garment shop at just eight years old. After earning a psychology degree from the University of Minnesota in 1958, he embarked on a successful career in sales and marketing, eventually founding Contech, Inc., a company specializing in sealants and coatings.

In 1986, Denny purchased a bank in Sioux Falls, renaming it First PREMIER Bank. Under his leadership, the bank expanded into the credit card sector with PREMIER Bankcard, establishing it as one of the nation's strongest financial institutions. This success allowed Denny to focus on his philanthropic endeavors later in life.

Throughout his lifetime, Denny made significant contributions to various charitable organizations, particularly those benefiting children, healthcare, education, and the arts. His notable donations include a $2 million gift to the Children’s Home Society of South Dakota in 1999 and a groundbreaking $400 million contribution to the Sioux Valley Health System in 2007, which transformed into Sanford Health.

His philanthropy extended beyond South Dakota, funding projects in communities where he felt a strong connection. Denny's contributions exceeded $4 billion, supporting initiatives such as the Sanford Consortium for Regenerative Medicine in San Diego and the Sanford-Burnham-Prebys Medical Discovery Institute in La Jolla, California.

Recognized as one of the 50 most generous philanthropists by the Chronicle of Philanthropy, Denny received numerous awards, including the Horatio Alger Association Distinguished American Award. He was known for his humility and compassion, living by the motto, 'Aspire to inspire before you expire.'

In addition to his philanthropic work, Denny cherished time with his family and friends, enjoying hobbies like golf and sailing. He is survived by his brother Charles 'Chuck' Sanford, his sons Scott and Bill, and three grandchildren. Arrangements for a family service and community celebration are pending, with requests for memorial contributions to be made to charities of choice.