US President Donald Trump has signed an order imposing new tariffs and minimum import prices on products made using polysilicon, a key material used in solar panels and semiconductors.
Under the order, the products will face a 15% tariff from Dec 4. Minimum import prices for polysilicon and products such as wafers and solar cells will also take effect on the same date.
The White House said the measures aim to create a level playing field for US producers of these strategic goods and encourage the domestic production of the industries involved.
It added that polysilicon is an important component in the semiconductor industry and has defence-related uses.
US seeks to rebuild domestic supply chain
The move follows a year-long Commerce Department investigation into imports of polysilicon.
Commerce Secretary Howard Lutnick described polysilicon as a ‘foundational product’ used in the production of chips.
‘We’re making the products here, but we need the supply chain here. So this will bring the supply chain here,’ Lutnick told reporters at the White House on Thursday.
He said the new minimum prices were intended to prevent Chinese products from being dumped in the US market, while the tariffs were aimed at encouraging production in the country.
The White House said the US share of global polysilicon production capacity had fallen from 50% in 2005 to less than 2% in 2024.
Move follows Section 232 investigation
The Commerce Department launched its investigation into polysilicon imports in July 2025 under Section 232 of the Trade Expansion Act of 1962.
Trump had previously used the same authority to impose steep tariffs on imports of steel, aluminium, automobiles and other products.
Although the investigation did not initially identify specific countries, China is a major player in the global solar supply chain.
The latest measures mark another step in Trump’s tariff policy since his return to the White House last year.
While the Supreme Court struck down a wide range of the administration’s tariffs in February, sector-specific tariffs imposed under Section 232 investigations remain in place.
Last month, Trump also used different legal justifications to impose new duties on 60 trading partners, rebuilding his tariff measures following the Supreme Court setback.
