Bayport is a hamlet and census-designated place (CDP) in the Town of Islip, Suffolk County, New York, United States, on Long Island. The population was 8,896 at the 2010 census.
Bayport is in the southeast part of the Town of Islip.
The community borders the Great South Bay, Sayville and the hamlet of Blue Point.
Bayport is located at 40°44′52″N 73°3′15″W (40.747858, -73.054216).
According to the United States Census Bureau, the CDP has a total area of 3.8 square miles (9.8 km2), of which 3.7 square miles (9.6 km2) is land and 0.1 square miles (0.3 km2) (2.37%) is water.
As of the census of 2000, there were 8,662 people, 3,222 households, and 2,303 families residing in the CDP. The population density was 2,332.8 per square mile (901.5/km2). There were 3,325 housing units at an average density of 895.5/sq mi (346.0/km2). The racial makeup of the CDP was 96.06% White, 0.89% African American, 0.07% Native American, 1.18% Asian, 0.82% from other races, and 0.98% from two or more races. Hispanic or Latino of any race were 3.93% of the population.
There were 3,222 households, out of which 33.8% had children under the age of 18 living with them, 60.0% were married couples living together, 8.8% had a female householder with no husband present, and 28.5% were non-families. 23.0% of all households were made up of individuals, and 11.4% had someone living alone who was 65 years of age or older.