East Farmingdale is a hamlet and a census-designated place (CDP) in Suffolk County, on Long Island, in New York. The population of the CDP was 6,484 at the 2010 census. Located in the Town of Babylon, the residents are served by the Farmingdale Post Office. In the past, some or all East Farmingdale was proposed to become part of the never-realized Incorporated Village of Half Hollow Hills.