
St. Anthony Hall is an American fraternity and literary society. Its 11 active chapters go by different names on different campuses, including Saint Anthony Hall, The Order of St. Anthony, the Fraternity of Delta Psi (ΔΨ), St. A's, the Hall and the Number Six Club. Its first chapter (Alpha) was founded at Columbia University on January 17, 1847, the feast day of St. Anthony.
As of 2016, nearly all chapters of St. Anthony Hall have gone co-ed; only three (University of Pennsylvania, University of Virginia, and Ole Miss) remain all-male. At both the University of North Carolina (1967) and Ole Miss, St. Anthony Hall was the first campus fraternity to admit African-American members, in 1967 at the University of North Carolina. The chapter at Yale University was, in 1961, the first chapter of the fraternity to admit a person of color (from Trinidad and Tobago), and would later also be the first to admit women, in 1971.
In 1879, Baird's Manual characterized the fraternity as having "the reputation of being the most secret of all the college societies." References to St. Anthony Hall have appeared in the work of F. Scott Fitzgerald, John O'Hara, and Tom Wolfe.