Section 232 Metals Tariffs Expanded and Recalibrated: What Importers Need to Know

President Trump issued a sweeping proclamation on April 2, 2026, modifying the existing trade remedy tariff regimes on aluminum, steel, and copper products (as well as derivative products) under Section 232 of the Trade Expansion Act of 1962. The proclamation significantly expands tariff coverage, clarifies valuation rules, restructures derivative-product treatment, and institutes new rate tiers tied to country of origin and metal sourcing. Most notably, the proclamation mandates that Section 232 duties now apply to the full customs value of covered products and derivatives, rather than just the value of the actual metal content.

These measures, effective for covered goods entered on or after April 6, 2026, materially alter duty exposure for a broad range of importers across the manufacturing, construction, energy, transportation, and consumer products sectors. They also change the prior Department of Commerce (Commerce)-led derivative inclusion processes established under earlier proclamations. Going forward, Commerce and the United States Trade Representative (USTR) jointly may add new derivative articles on a rolling basis if import trends threaten to undermine the Section 232 objectives.

Background

Since 2018, the U.S. has imposed tariffs on aluminum and steel — and more recently copper — after determining under Section 232 that imports of these metals threatened to impair national security. Those actions established tariff regimes that included additional duties on covered metal articles and certain derivative products, together with processes allowing Commerce to expand coverage over time. Based on continued monitoring by Commerce, President Trump determined via the new Proclamation that further adjustments were necessary to improve the effectiveness of the regimes and prevent circumvention of the prior Section 232 tariffs.

Key Changes to Section 232 Duties

The main changes to these trade remedy tariffs are as follows:

Tariffs Apply to Full Customs Value

Section 232 duties on aluminum, steel, and copper articles — and all covered derivatives — now apply to the entire customs value of the imported product and are not based on the percentage of metal content. This change represents a fundamental clarification and shift from prior practice by CBP’s Base Metals Center of Excellence which, without following any notice of proposed rulemaking or other administrative process, began increasing duties, i.e., “rate-advancing” importers’ entries, starting in late 2025, which had at that time only calculated the Section 232 duties on the metal content of the imported article in accordance with guidance from CBP headquarters.

It should be noted that CBP’s prior practice has been challenged in a lawsuit at the U.S. Court of International Trade (CIT) and that entries before April 6, 2026 need not pay any additional duty bills if the importer files Protests with CBP based on the pending CIT litigation. If CBP prevails in the litigation, those duty bills would need to be paid with interest.

New Tiered Duty Structure (Up to 50%)

Covered products are now subject to tiered ad valorem rates based on product tariff code classification and sourcing (i.e., country of origin) based on four Annexes to the new Proclamation. If any goods are listed in multiple Annexes containing multiple covered metals, they are subject to only one Section 232 duty (i.e., the tariffs will not stack with each other). This reduced duty framework for all items listed in Annex III will expire on December 31, 2027.

• 50% ad valorem: Applies to aluminum and steel articles, most copper articles, and certain derivative products listed in Annex I A.
• 25% ad valorem: Applies to certain copper articles and aluminum and steel derivatives listed in Annex I B. A reduced rate of 15% applies for aluminum or steel products of the UK that are composed entirely of aluminum that was smelted and cast, or of steel melted and poured, in the UK. A 10% rate applies for articles composed entirely of aluminum or copper that was smelted and cast, or of steel melted and poured, in the U.S.
• Reduced 15% sum of HTSUS Column 1 Duty Rate and Section 232 ad valorem rate: For certain steel and aluminum derivative products listed in Annex III, products with a Column 1 Duty Rate of under 15%, i.e., the Normal Trade Relations (NTR) duty rate, have Section 232 ad valorem tariffs added to bring the combined sum to 15%. If the NTR duty rate is already 15% or more, no additional Section 232 tariffs will be applied. However, if the item is a derivative article composed entirely of aluminum that was smelted and cast, or of steel melted and poured, in the U.S., the Section 232 tariff will be 10%. If the item is imported from a trading partner with whom the U.S. does not maintain NTR, the tariff rate will be 25%.

Terminated ad valorem rate 

A long list of articles, including numerous consumer goods, chemicals, machinery, motorcycle parts, and medical products, were removed from Section 232 coverage entirely under Annex III.

15% ‘de minimis’ content threshold

For articles classified in the listed provisions of Annex IV outside of chapters 72, 73, 74, or 76, the Section 232 ad valorem rate will apply only where the weight of the applicable metal (steel, aluminum, or copper) is at least 15% of the weight of the imported article. If an article is classified in a provision present on multiple lists containing multiple types of applicable metal, the aggregate weight of the metals must be used to determine whether the 15% minimum threshold applies.

Manufacturing Drawback Available

Manufacturing drawback claims can be made to reclaim 99% of the tariffs and duties paid on articles that satisfy the following conditions:

1. The article is listed in a classification contained in Annex I-B or Annex III or is later included in the tariffs by the USTR and Commerce; 
2. The article is not a type of merchandise subject to an antidumping or countervailing order, regardless of whether the article is from the country listed in the order;
3. The article is a product of Trade Agreement Partners, composed of Canada, the EU, Japan, Mexico, South Korea, the UK, and any other trading partner with which a final Agreement on Reciprocal Trade is concluded; and
4. The metal content of the article is composed entirely of aluminum or copper smelted and cast, or steel melted and poured, in one of the Trade Agreement Partner countries mentioned above.

Practical Considerations for Importers

The breadth and immediacy of the April 2026 Section 232 changes present significant operational and compliance risks for importers. Duty exposure may increase substantially — particularly for derivative articles with relatively low metal content but high overall customs value now subject to full value tariffs.

Importers will need to reassess HTSUS classification, Chapter 99 reporting, and valuation methodologies to qualify for reduced rates where available, under the new Proclamation. Enhanced documentation to substantiate metal origin, including smelting, casting, melting, and pouring processes will also be required. 

Products previously excluded from Section 232 coverage may now be fully dutiable, while others have been removed from scope entirely—necessitating a detailed, line by line and entry-by-entry product review.

Additional considerations include limitations on duty mitigation strategies. Goods admitted into U.S. foreign trade zones on or after April 6, 2026 must enter under privileged foreign status, reducing flexibility for tariff planning. Manufacturing drawback is also significantly curtailed and available only for a narrow set of products meeting stringent criteria.

Most importantly, importers should promptly identify all impacted products across Annexes I A, I B, II, III, and IV; model increased duty liability under a full value tariff framework; coordinate closely with brokers on updated Chapter 99 reporting; and evaluate sourcing, pricing, and contractual strategies in anticipation of elevated tariff rates through at least 2027 and potentially beyond.

CBP is expected to issue additional notices via its Cargo Systems Messaging Service (CSMS) and further technical guidance addressing enforcement, documentation standards, and ACE updates.