On August 6, 2026, President Trump issued a proclamation under Section 232 of the Trade Expansion Act of 1962, establishing new import restrictions on polysilicon and a range of downstream products. This is the result of a process that started in July 2025. The Administration concluded that increased reliance on foreign sources for these materials raises concerns over the resiliency of supply chains that support semiconductor manufacturing, solar technologies, defense applications, and other strategically important industries.
The action follows a Commerce Department investigation examining the condition of the domestic polysilicon industry and related manufacturing sectors. According to the investigation, US production capacity in these sectors has declined while global output has expanded rapidly, contributing to greater dependence on imported products throughout portions of the semiconductor and solar manufacturing value chains.
A central feature of the new measures is the creation of a minimum import price (MIP) mechanism applicable to polysilicon and certain derivative products. Starting 120 days from the signing of the proclamation (i.e., December 4, 2026), minimum import prices will be set at US$21 per kilogram for polysilicon, US$100 per kilogram for polysilicon ingots and wafers, US$0.22 per watt for solar cells, and US$0.38 per watt for solar modules. Importers will be required to provide documentation demonstrating compliance with the program or may face additional duties designed to account for any shortfall below the applicable threshold.
The proclamation also imposes an additional 15% ad valorem tariff on covered polysilicon derivatives, including products such as silicon wafers, photovoltaic cells, and solar modules, also effective December 4, 2026. The Administration has indicated that the combined tariff and pricing measures are intended to encourage greater investment in US-based manufacturing and expand domestic production capabilities across the polysilicon supply chain.
The new framework also includes certain country-specific adjustments. For products originating in Japan, Korea, Taiwan, Switzerland, Liechtenstein, and European Union member states, the combined effect of the Section 232 tariff and ordinary customs duties generally will not exceed 15%. Products originating in the United Kingdom generally will be subject to a 10% tariff rate under the proclamation. The Administration also reserved authority to modify the treatment of imports from trading partners that adopt comparable import-control measures.
In addition, the proclamation authorizes the Commerce Department to establish a program supporting investment in domestic production facilities for polysilicon, ingots, wafers, and cells. Companies that submit and obtain approval of qualifying domestic investment plans may become eligible for tariff exemptions on specified production equipment and inputs during project development, subject to compliance with applicable conditions and reporting requirements. This is the latest development across numerous actions affecting this space, including significant trade and intellectual property disputes between domestic producers and foreign sources on downstream products, such as solar cells and modules. In a dispute before the US International Trade Commission under Section 337 of the Tariff Act of 1930, certain producers of solar panels are seeking an import ban on products purportedly produced in violation of US patents. Meanwhile, the Biden Administration’s June 2022 proclamation under Section 318 to temporarily suspend the application of antidumping and countervailing duties to specific imports of solar cells and modules due to a declared energy emergency. That action was challenged before the US Court of International Trade and is currently on appeal before the US Court of Appeals for the Federal Circuit. This is on top of significant disruptions caused by alleged forced labor concerns in the polysilicon supply.
Businesses involved in or relying on semiconductor, solar, and advanced manufacturing supply chains should evaluate whether relevant products fall within the scope of the new measures and assess the potential impact on sourcing, pricing, and customs compliance. Importers also may wish to review existing contractual arrangements, analyze future duty exposure, and consider whether the new domestic manufacturing incentives present strategic opportunities.
