Hilltop is a census-designated place (CDP) in Fayette County, West Virginia, United States. Hilltop is located on state routes 16 and 61, south of Oak Hill. Hilltop has a post office with ZIP code 25855. As of the 2020 census, its population was 528 (down from 624 at the 2010 census). Hilltop was formerly an incorporated municipality.