Hornellsville is a town in Steuben County, New York, United States.

[3] The Town of Hornellsville is at the western border of the county, and surrounds the city of Hornell.

The name Hornellsville is used only in real estate or legal contexts, but rarely in conversation.

The town was first settled circa 1790 in the vicinity of the modern city of Hornell.

Territory from Hornellsville was used to form the Towns of Hartsville (1844) and part of Fremont (1854).

The Southern Tier Expressway (Interstate 86 and New York State Route 17) passes through the north part of the town.