New Tariffs and Minimum Import Prices on Polysilicon, Derivatives and Solar Products

The U.S. is implementing minimum import prices (MIPs) and a new 15% tariff on imported polysilicon, derivatives, and solar products, as well as a new onshoring incentive program starting December 4, 2026. These new trade measures — imposed under Section 232 of the Trade Expansion Act of 1962 — are established under Proclamation 11052 released by President Trump on August 6, 2026.

The December 4 effective date leaves importers a short window to confirm product coverage, test pricing against the new minimum import prices, update entry documentation, and reassess supply contracts. Companies importing polysilicon, ingots, wafers, solar cells, and solar modules should begin preparing now for significant changes in sourcing, contracting, and entry documentation.

National Security Basis for Action

The Proclamation follows a Section 232 investigation in which the Secretary of Commerce concluded that polysilicon and its derivative products enter the U.S. in quantities and under circumstances that threaten to impair U.S. national security and have significantly eroded domestic production capacity. 

Polysilicon is the base material for both semiconductors and solar products. The Secretary found that the U.S. share of global polysilicon production capacity fell from 50% in 2005 to less than 2% in 2024, while the U.S. share of global semiconductor wafer fabrication capacity fell from 37% in 1990 to 10% in 2024. Further, the Secretary found that global polysilicon production has grown by more than 270% since 2020, with inventories reaching a record high by the end of 2024, contributing to a global oversupply that the Trump administration views as having eroded U.S. industry. The Proclamation also notes that the U.S. is virtually entirely dependent on imports of solar ingots, wafers, and cells.

To address these concerns, the Proclamation adopts two primary measures: 

1. Minimum import prices for polysilicon and polysilicon derivatives; and 
2. A 15% ad valorem tariff on downstream polysilicon derivatives. 

Both measures apply to goods entered for consumption, or withdrawn from warehouse for consumption, on or after December 4, 2026. The MIP program and the 15% ad valorem tariff are separate remedies and may apply to the same entry. The 15% ad valorem tariff will apply only to downstream derivatives, including ingots and wafers, cells, and modules; raw polysilicon will only be subject to the MIP mechanism and ordinary duties but not the additional 15% tariff.

The Proclamation also directs the Secretary of Commerce to establish a program to encourage new or expanded U.S. production facilities of raw polysilicon, ingots, wafers and cells.

The new tariffs replace the narrower Section 201 safeguard on solar cells and modules imposed during President Trump's first term and that expired in February 2026.

Minimum Import Price Program

The MIP is measured against the first arm’s-length U.S. sale price of a covered product, or of downstream products made from it, rather than solely against the product’s entered value at importation. The Proclamation establishes the following minimum price floors for covered imports entering the U.S. market:

• $21/kg for raw polysilicon 
• $100/kg for polysilicon ingots and wafers;
• $0.22/watt for solar cells; and
• $0.38/watt for solar modules.

Annex I to the Proclamation identifies the tariff classifications covered by each price point. The Secretary of Commerce is authorized to adjust the minimum prices and relevant Harmonized Tariff Schedule of the United States (HTSUS) provisions. Annex II sets out the grounds for avoiding the MIP-based duties.

To implement the MIP program, Customs and Border Protection (CBP) will require importers to submit entry documentation certifying one of the following:

• The first arm’s-length U.S. sale of the imported merchandise (or downstream products made from it) at or above the applicable MIP; or 
• The sale is made under fixed terms in a time-limited contract entered into before August 6, 2026.

Penalties will apply for noncompliance, with the amount depending on the infraction. Notably, if CBP determines that an importer's documentation was materially inaccurate or that it materially failed to comply with its certification, the importer and its affiliates may be prohibited from importing covered products into the U.S., along with the imposition of monetary penalties.

Importers should expect CBP to scrutinize supporting documentation. 

Additional 15% Ad Valorem Tariff

In addition to the MIP program, the Proclamation establishes a 15% ad valorem duty on imports of specified polysilicon ingots and wafers, solar cells, and solar modules identified in the annexes, implemented through new HTSUS heading. Special rules will apply for covered products from the following jurisdictions that have trade agreements with the U.S.:

• Japan, Korea, Liechtenstein, Switzerland, Taiwan, and EU member states: the Section 232 tariff and the “Column 1 rate of duty” will equal 15%; and
• U.K.: the Section 232 tariff will be 10 percent.

These new duties apply in addition to any other duties, taxes, fees, and charges otherwise applicable to the merchandise (including antidumping/countervailing duty orders, which continue to be imposed without regard to the origin listed in the order), except as otherwise specified. However, as noted above, raw polysilicon will be subject to the MIP rates but not the additional 15% tariff.

Manufacturing drawback will remain available in the following circumstances:

• The article is not subject to an antidumping or countervailing duty order;
• It is a product of a trade agreement partner; and 
• The polysilicon content comes entirely from such a partner.

Onshoring Incentive Program

The Proclamation authorizes the Secretary of Commerce to establish a program to incentivize investment in the domestic production of raw polysilicon, ingots, wafers, and cells, with a waiver of the relevant Section 232 tariffs. 

Companies may submit onshoring plans committing to build, refurbish, or expand a qualifying U.S. facility, with construction to begin by January 20, 2029. If approved, the Secretary may allow the company to import necessary production equipment and Covered Products — in volumes commensurate with the committed investment — without paying the Section 232 duties during the facility’s construction period, contingent on continued progress under the plan. These benefits may be rescinded in cases of fraud or deliberate misrepresentation, and CBP may then collect the resulting duties and applicable penalties.

Similar to other recent actions involving the aluminum and pharmaceutical sectors, the onshoring incentive program ties tariff relief to manufacturing onshoring commitments. 

BDO Perspective

The Proclamation introduces a new compliance framework for importers of covered products that likely will affect landed costs, sourcing decisions, contract pricing, and entry documentation requirements. Importers will need to determine whether their products are covered, assess whether transaction values meet the applicable minimum import prices, account for potential tariff stacking with other duties, and prepare documentation to support compliance. 

Companies that import covered products should begin reviewing supply chains, customer and supplier contracts, related-party transactions, and CBP documentation controls ahead of the December 4 effective date.