Located in the Firth of Clyde to the south of the island of Great Cumbrae, within North Ayrshire, Little Cumbrae is a small island measuring 313 ha (773 acres) and reaches a high point of 123m (403 feet) at the centrally situated Lighthouse Hill. This was the site of the open fire beacon that acted as lighthouse before the creation of the automatic one on the western shore. Privately owned, the island has no permanent human population but substantial rabbit one, and is now regarded as a nature reserve. Its population is recorded as 8 (1961), 14 (1971), 6 (1981), 6 (1991) and 0 (2001). The principal building of the island is Little Cumbrae House, located on the eastern shore of the island, and overlooking the nearby Castle Island. It is on this island that a ruined castle keep, dating from the 1527, can be found.
After a failed attempt to turn the island into a luxury resort, the island was put up for sale in 2005 and, after limited interest, was eventually sold for £2.5 million in 2008.
In 1998, the island gave its name to a glacier in Greenland thanks to a Scottish Mountaineering Club expedition.