Section 232 metals modifications take effect

At 12:01 a.m. eastern daylight time on 8 June 2026 the § 232 tariff modifications established by Proclamation 11032 of 1 June 2026, “Further Adjusting the Tariff Regimes for Imports of Aluminum, Steel, and Copper into the United States,” entered force; U.S. Customs and Border Protection began collecting under modified HTSUS Chapter 99 subchapter III subheadings drawn from the proclamation’s Annex I-A (primary metals), Annex I-B (derivative articles) and Annex I-C (industrial-equipment categories) — the unified 9903.82.01 through 9903.82.26 series — pursuant to CBP Cargo Systems Messaging Service Bulletin CSMS # 68855869 of 5 June 2026.¹²³ The 50 percent standard ad valorem duty on covered primary aluminum, steel and copper imports takes effect; the 25 percent rate applies to covered derivative articles; the 15 percent rate (or rate-equivalent) is available for specified industrial-equipment categories under a four-tier country-of- origin structure in Annex I-C; the qualifying U.S.-melted-or- poured (steel) and U.S.-smelted-and-cast (aluminum) content threshold for preferential treatment is lowered to 85 percent from the prior 95 percent.¹³ The framework runs through 31 December 2027, after which covered products revert to the rates set by Proclamation 11021 of 2 April 2026.³

1. CBP applies the new schedule to entries released on or after 12:01 a.m. EDT on 8 June 2026; the proclamation contains no exception for goods already in transit at the effective moment, consistent with prior § 232 actions.³⁴ The “melted and poured” (steel) and “smelted and cast” (aluminum) origin certifications are made at entry under the proclamation Annex and the controlling CBP CSMS guidance; CBP audits eligibility on a per-entry basis, with importers liable for unpaid duties and § 1592 penalties where the certification is incorrect.⁵⁶

2. The Annex I-C industrial-equipment tier operates a four- tier country-of-origin rate structure: a 25 percent general rate; a calibrated 15 percent effective rate for products from Argentina, Ecuador, El Salvador, Guatemala, Japan, the Republic of Korea, Liechtenstein, Switzerland, Taiwan, the United Kingdom and European Union member states; a 10 percent rate for products incorporating U.S.-origin metals; and, for USMCA-qualifying Canadian and Mexican products, a 25 percent rate on the non-U.S. metal content with a 15 percent rate floor.³ The Secretary of Commerce will issue guidance to U.S. Customs and Border Protection on assessing U.S. content for USMCA products.³ The proclamation operates as the § 232 vehicle modifying the framework most recently overhauled by Proclamation 11021 of 2 April 2026, following the U.S. Supreme Court’s 20 February 2026 ruling in Learning Resources, Inc. v. Trump that IEEPA does not authorise tariffs and the U.S. Court of International Trade’s 7 May 2026 ruling holding the § 122 surcharge unlawful with an injunction limited to three plaintiffs.⁷⁸

3. The anti-stacking precedence regime under Executive Order 14289 of 29 April 2025 (closed set covering five enumerated actions including § 232 steel and § 232 aluminum) continues to operate; the relationship between the EO 14289 closed set and the proclamation’s revised rate structure for derivatives, industrial-equipment categories and copper coverage is to be verified against the proclamation’s coverage and stacking paragraphs.⁹ Industry and foreign-government on-record responses to the take-effect date are reported separately (see Section 232 metals week one: downstream effects).