Cohn and his wife are founding board members of the New York University Child Study Center. The couple funded the Pevaroff Cohn Professorship in Child and Adolescent Psychiatry at the New York University School of Medicine in 1999. He financed the Gary D. Cohn Endowed Goldman Sachs Chair in Finance and the Gary D. Cohn Scholarship both at American University, his alma mater. In 2015 Cohn financed the Gary D. Cohn and Brother Robert LaVelle Endowed Scholarship in honor of Brother Robert LaVelle, who was retiring after 35 years as head of Gilmour Academy, where Cohn attended high school.