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, and Spain, and Saudi Arabia; and a 55% interest in the Portland aluminium 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 as part of the demerger of the WMC Group.