Mostyn House School was a school that was originally opened in Tarvin, and moved to Parkgate, Cheshire in 1855. From 1862 until it closed in 2010, it was run by the Grenfell family, originally as a boys' boarding school, and latterly as a co-educational day school.
The chapel was designed by Frederick Fraser and Warburton, with input by the headmaster of the school, A. G. Grenfell. It is built in red Ruabon brick with terracotta dressings, and has a red tiled roof with a finial at the east end. The chapel consists of a nave and chancel in a single range, an apsidal east end, and a west bellcote. The furnishings are in collegiate style, designed by Frederick Fraser. In the windows is painted glass made by Morton and Company of Liverpool.
Sir Wilfred Grenfell (1865–1940), medical missionary to Newfoundland and Labrador, was born in Parkgate and was a pupil at the school. The 6th Duke of Westminster's children attended Mostyn House, including Hugh Grosvenor, 7th Duke of Westminster.
Other notable alumni include: