Alumina Limited, through its 40% interest in Alcoa World Alumina and Chemicals, engages in bauxite mining, alumina refining, and aluminum smelting businesses. The company has a network of bauxite mines and alumina refineries in Australia, Guinea, Brazil, Spain, and Saudi Arabia; and holds a 55% interest in the Portland aluminum smelter in Victoria, Australia. It is also involved in shipping operations.

The company was formerly known as WMC Limited and changed its name to Alumina Limited in December 2002.