Hill House in Helensburgh, Scotland is one of Charles and Margaret Macdonald Mackintosh's most famous works, probably second only to the Glasgow School of Art. It was designed and built for the publisher Walter Blackie in 1902 – 1904.
In addition to the house, Mackintosh designed most of the interior, furniture and fittings. Mackintosh's attention to detail extended to prescribing the colour of cut flowers that the Blackies might place on a table in the living room.
In 1982 the house was donated to the National Trust for Scotland which maintains it and opens it to visitors.
The top floor was leased to the Landmark Trust in 1978 for use as holiday accommodation but since 2011 has been operated as a holiday rental by the National Trust for Scotland. It accommodates six people.