South32 shareholders have approved the sale of its aluminium business to Alcoa for up to $5.6 billion, with 99.18% voting in favour. The deal leaves South32 focused on copper, zinc, silver, lead and manganese.
At a glance
- Alcoa will gain Worsley Alumina in Australia, the Hillside smelter in South Africa and stakes in three Brazilian operations.
- South32 expects the deal to complete in the first half of 2027, subject to regulatory approvals.
- Hillside and Worsley produced more than 95% of South32's operational emissions in its 2026 financial year.
Background
Aluminium is made in two main steps. Bauxite ore is refined into alumina, a white powder, and alumina is then smelted into aluminium metal using large amounts of electricity. South32 owns assets at every stage of that chain, from the MRN bauxite mine to the Hillside smelter, which is why the sale is called a value chain deal.
What happened
South32 shareholders voted to sell the company's aluminium value chain assets to Alcoa at its annual general meeting on October 15, Aluminium International Today reported. Holders of 99.18% of shares approved the deal, Business Day said. The sale is worth up to $5.6 billion.
Alcoa will acquire South32's 86% of Worsley Alumina in Western Australia and all of the Hillside Aluminium smelter at Richards Bay, South Africa. It will also take 33% of the MRN bauxite mine, 36% of the Brazil Alumina refinery and 40% of the Brazil Aluminium smelter. The MRN stake is subject to pre-emptive rights held by the mine's other partners.
Why South32 is selling
South32 wants to concentrate on higher-margin metals. Chief executive Matt Daley said the company will become a simpler business focused on copper, zinc, silver and lead, along with its position as a large manganese producer. He said South32 expects to cut overheads by about $125 million a year.
The sale also changes South32's carbon footprint. Aluminium smelting and alumina refining use a lot of energy, and Hillside and Worsley produced more than 95% of its operational emissions in the 2026 financial year. Chair Stephen Pearce called the deal transformational.
What comes next
Daley said he expects the deal to complete in the first half of 2027, subject to regulatory approvals. South32's growth will then rest on copper and zinc, including its Hermosa project and the Sierra Gorda copper mine. For Alcoa, the purchase adds major alumina and smelting capacity in Australia, South Africa and Brazil.
Our read
Outlook: neutral. The sale changes who owns these plants, not how much aluminium or alumina they produce. It has no direct effect on prices.
What to watch
- Regulatory approvals needed before the deal can complete in the first half of 2027.
- Whether MRN's other partners use their pre-emptive rights over South32's 33% stake.
For information only, not investment advice.
Aluminium price in India
metalscost.com India reference price as of 2026-10-16.
Detailed analysis
Timeline
- 2026-10-15: South32 shareholders approve the sale of its aluminium assets to Alcoa.
Supply Drivers
Ownership of the Hillside smelter and Brazilian assets moves to Alcoa, but output stays the same.
Refinery Output
Alcoa gains control of Worsley Alumina, a major alumina refinery, adding to its own refining base.
What could lift prices
- A larger Alcoa may have more control over alumina and aluminium supply.
- Power problems have already shut smelters, such as Mozal in Mozambique, which went on care and maintenance in March.
What could weigh on prices
- The deal does not add or remove any aluminium supply.
- Integration risks are borne by Alcoa, not by the aluminium market.
Country impact
| Country | Impact | Reason |
|---|---|---|
| Australia | Medium | Worsley Alumina, one of the deal's largest assets, is in Western Australia. |
| South Africa | Medium | The Hillside smelter at Richards Bay passes fully to Alcoa. |
| Brazil | Low | Alcoa takes South32's minority stakes in three Brazilian operations. |
Industry impact
| Industry | Effect | Reason |
|---|---|---|
| Aluminium Smelting & Refining | Neutral | Assets change hands, but production capacity stays the same. |
Who gains, who loses
- South32: It becomes a simpler base metals company and expects about $125 million a year in lower overheads.
- Alcoa: It gains major alumina and smelting assets across three countries.
- South32 aluminium exposure: Investors who held South32 for aluminium will lose that exposure after completion.
Other ways this could play out
- If regulators approve the deal quickly, it could close in early 2027.
- If MRN's partners use their pre-emptive rights, that stake could go to them instead of Alcoa.
Price risks
- A regulatory delay would push back completion beyond the first half of 2027.
- Power supply problems at smelters could affect output regardless of ownership.
Technical view
Price is trading below both its 20-period and 50-period moving averages, a bearish alignment.
Computed from metalscost.com's own stored price history.
Australia
South Africa
Brazil