Mattituck is a hamlet and census-designated place in Suffolk County, New York, United States. Located in the Town of Southold, Mattituck CDP roughly corresponds to the hamlet by the same name. The community has a total area of 9.3 square miles (24.2 km2), of which 9.0 square miles (23.3 km2) is land and 3.88% is water.
Mattituck is sandwiched by the adjacent hamlets of Laurel and Cutchogue. It is bordered by the Long Island Sound to the north and Great Peconic Bay to the south. The Mattituck Inlets flow in from the Long Island Sound, bisecting the north half of the hamlet. North Road and Main Road pass through in the middle of the hamlet serving as the commercial thoroughfare, with Main Road intersecting with New Suffolk Avenue going southeast towards the hamlet of New Suffolk.
Landmarks: Richard Cox House, Mill Road Preserve, Breakwater Beach, Bailie Beach Park, Bailie Beach Scout Lodge, Landcraft Garden Foundation, Wolf Pit Pond, Strawberry Fields, Bay Avenue Park, and Veterans Beach. Mattituck-Cutchogue Jr.Sr High School is located in the middle of North Road and Main Road and the only school serving the area.
Houses of worship are Our Lady of Good Counsel Church, Mattituck Presbyterian Church, Advent Lutheran Church, Unity Baptist Church, The Church of The Redeemer, Unity Baptist Church, Chabad of North Fork, Transfiguration of Christ Greek Orthodox Church
Mattituck Coordinates: 40°59′41″N 72°32′14″W