It serves the boroughs of Sligo and Rimersburg, as well as the townships of Madison, Toby, and Piney.

Union School District encompasses approximately 80 square miles.

The district operates two schools: Sligo Elementary (K–5) and Union Junior/Sr High (6-12).

The Riverside Intermediate Unit provides support services and therapy to special education students.

Occupational training and adult education in various vocational and technical fields are provided by the Clarion County Career Center.