The community of Mason City and countless colleagues across the state of Iowa join in deep mourning following the passing of John W. Colloton, who died peacefully at home on November 14, 2025, at the age of 94. A distinguished alumnus of St. Joseph’s High School and a magna cum laude graduate of Loras College, John devoted his life to service, leadership, and the advancement of healthcare in Iowa and beyond.
After serving two years in the U.S. Army in Germany, John earned his Master’s Degree in Hospital and Health Administration from the University of Iowa—an achievement that marked the beginning of one of the most influential careers in American academic medicine. Joining the University of Iowa Hospitals in 1956, John went on to serve the institution for 45 years, including 23 as Director and Chief Executive Officer of UI Hospitals & Clinics. His visionary leadership transformed UIHC from an indigent care facility into one of the nation’s premier academic medical centers. Under his guidance, UIHC underwent a historic $500 million expansion—completed without state tax support—quadrupling the size of the medical complex, significantly expanding clinical services, and building a world-class reputation recognized nationwide.
John’s many honors speak to the magnitude of his impact. He was elected to the National Academy of Medicine, served as Chairman of the Association of American Medical Colleges, and received the American Hospital Association’s Distinguished Service Award, among numerous other accolades. His legacy lives on through the John W. Colloton Pavilion at UIHC, endowed academic chairs in his name, and the many colleagues, physicians, and leaders he mentored throughout his extraordinary career.
Beyond professional accomplishments, John was a man deeply devoted to family. He married Mary Ann Hagglund in 1960, and together they raised three children—Steven, Laura, and Ann—who, along with their spouses and grandchildren, survive him. He cherished moments spent fishing in Canada with lifelong friends, traveling with Mary Ann, cheering on the Hawkeyes, and gathering with loved ones for holidays and celebrations.
As we extend our heartfelt condolences to the Colloton family, we honor a man whose integrity, leadership, and generosity shaped institutions, strengthened communities, and enriched countless lives. John W. Colloton leaves behind a legacy of service that will continue to inspire for generations. May his memory bring comfort, pride, and peace to all who were fortunate to know him.
