Sag Harbor is an incorporated village located in Suffolk County, New York, within the United States. Situated on eastern Long Island, it occupies a unique administrative position spanning two towns: approximately three-fifths of its area lies within Southampton, while the remaining two-fifths fall under East Hampton, with Division Street serving as the dividing boundary. The village developed historically as a working port on Gardiners Bay, leveraging its coastal geography to become a significant maritime hub in the region.