Barnard Castle School (colloquially Barney School) is a co-educational independent day and boarding school in the market town of Barnard Castle, County Durham, in the North East of England. It is a member of The Headmasters' and Headmistresses' Conference (HMC). It was founded in 1883 with funding from a 13th-century endowment of John I de Balliol and the bequest of the local industrialist Benjamin Flounders.