Halesite is a hamlet and census-designated place (CDP) in the Town of Huntington in Suffolk County, on the North Shore of Long Island, in New York, United States.

[2] Halesite is named after Nathan Hale, a captain and spy in the Continental Army during the American Revolutionary War who arrived at Long Island at Huntington Harbor (at the site now named Halesite) just prior to his capture and execution.

[3] There is a rock with a tribute to him off the traffic circle at Mill Dam Road and New York Avenue.

Well-known persons who spent time or lived in Halesite include comedian/singer Fanny Brice, public servant and businessman George B. Cortelyou, and scientist Albert Einstein.

[4] Halesite is also served by a United States Post Office branch, although its zip code is the same as that of the hamlet of Huntington (11743).