Merrick is a hamlet and census-designated place (CDP) in the Town of Hempstead in Nassau County, on the South Shore of Long Island, in New York, United States.

The average monthly temperatures in the town centre range from 31.7 °F in January to 74.8 °F in July.

As of the census of 2000[update], there were 22,764 people, 7,524 households, and 6,478 families residing in the CDP.

There were 7,602 housing units at an average density of 1,811.1 per square mile (699.3/km2).

11.6% of all households were made up of individuals, and 6.6% had someone living alone who was 65 years of age or older.