Pitcairn is a town in St. Lawrence County, New York, United States.

The Town of Pitcairn is in the southwestern part of the county and is south of Canton.

Settlers began to arrive in the area circa 1825 near Portaferry Lake.

Part of the southern town line is the border of Lewis County.

17.6% of all households were made up of individuals, and 6.4% had someone living alone who was 65 years of age or older.