Tillson is a hamlet (and census-designated place) in Ulster County, New York, United States.

As of the census[4] of 2000, there were 1,709 people, 629 households, and 452 families residing in the CDP.

There were 676 housing units at an average density of 292.1 per square mile (112.8/km2).

There were 629 households, out of which 37.4% had children under the age of 18 living with them, 58.7% were married couples living together, 9.5% had a female householder with no husband present, and 28.0% were non-families.

20.0% of all households were made up of individuals, and 8.7% had someone living alone who was 65 years of age or older.