Castleton University was a public university in Castleton, Vermont, United States. In July 2023, Castleton University was dissolved and the campus was merged with Northern Vermont University and Vermont Technical College to form Vermont State University, of which it now serves as a branch campus. At the time of its closure, Castleton had an enrollment of 2000 students and offered more than 30 undergraduate programs, as well as master's degrees. It was accredited by the New England Commission of Higher Education.