Mount Vernon House (originally Windmill Hill House) is a house in Hampstead in the London Borough of Camden. It has been listed Grade II on the National Heritage List for England (NHLE) since May 1974. The garden wall is separately listed at Grade II. The house was built around 1726 and was altered in the early 19th century. It is rendered in stucco with a mansard roof. The house occupies the site of a windmill. It was constructed between 1725 and 1728 by a local Hampstead timbersmith, William Knight.