Except for a short stretch in Summertown, the entire route of SR 240 is known simply as Turnpike.

SR 240 begins as Turnpike just west of Deerfield at an intersection with US 64/SR 15.

It goes northeast along the southern edge of Laurel Hill Wildlife Management Area to pass through farmland and have a short concurrency with SR 241 before passing through Henryville, where it has an intersection with SR 242.

The highway then crosses the Buffalo River passes through a mix of farmland and wooded areas before entering Summertown, where it turns east to have a concurrency with SR 20 before turning south along Monument road and coming to an end at an intersection with US 43/SR 6.

The entire route of SR 240 is a two-lane highway.