Insh is an uninhabited island west of the island of Seil in the Firth of Lorn, Scotland. One of the Slate Islands, Insh Island lies a mile northeast of Ellenabeich in Seil. It is separated from it by the Sound of Insh. The island rises to 69m (226 feet) and is 36 ha in area. The private owner, David Brearley lived in a cave at the north end between 1973 and 2003. The Northern sea fan (Swiftia pallida) is found in the waters off Insh Island.