More than 500 workers at Geelong’s Point Henry aluminium smelter will find out in March whether they will keep their jobs, as Alcoa decides on the plant’s future.

The US global aluminium giant confirmed on Tuesday that a decision on the smelter’s future would be made by the end of March.

Alcoa agreed in 2012, when the Federal Labor government under Julia Gillard and Victorian government provided the company with $44 million in support, to keep the loss-making smelter open until June this year.

However, conditions for the global aluminium industry have not improved since then, with prices staying low amid a supply glut and slowing demand.

The price of aluminium was above $US2,000 a tonne two years ago but now is down to about $US1,770 ($A1,980.42).

Chinese smelters are over-producing and can do so at a far cheaper rate than can Australia, where there is greater regulation of the energy intensive industry, higher costs and a high dollar.

An Alcoa spokeswoman told AAP the company had committed to letting the 500 workers know by the end of the 2014 first quarter what the plant’s future would be.

The newer and larger Portland smelter, where Alcoa employs about 1,500 people and more than 400 contractors, is safe.

Aluminium industry analysts such as Credit Suisse believe the Point Henry smelter will be closed this year.

The new Coalition government led by Tony Abbott is more hostile to propping up uncompetitive industries with taxpayer money, which unions are calling for.

That was demonstrated when the government would not provide more subsidies to Holden ahead of its decision in December to stop car manufacturing in Australia.

But federal Industry Minister Ian Macfarlane has not ruled in or out more taxpayer support for Alcoa, amid fears of damaging political fallout tied to a likely rise in unemployment as Holden and Ford stop making cars in Australia in 2016 and 2017.

Australian Workers Union national secretary Paul Howes has said he’s hopeful but concerned for the smelter, pointing to cost savings.