Commack Union Free School District is a public school district located in Suffolk County, New York, United States. The school district straddles the towns of Huntington and Smithtown, with Townline Road as the dividing line. It serves the residents of Commack as well as parts of Dix Hills, Smithtown and East Northport. It served approximately 6,000 students during the 2018–2019 school year. There are four primary schools (grades K–2), two intermediate schools (grades 3–5), one middle school (grades 6–8) and one high school (grades 9–12).