Steel & Aluminum Tariffs: Section 232 Complete Guide

Steel and aluminum are subject to the highest Section 232 tariff rates in effect: 50% since June 4, 2025. These rates apply globally to imports from all countries, with one exception: the United Kingdom has a partial exemption at 25% for steel and aluminum. Section 232 tariffs on steel and aluminum have a longer history than most other tariff actions. They were first imposed at 25% (steel) and 10% (aluminum) in March 2018 under the Trump administration. Various country-specific exemptions were granted and revoked over the following years. In February 2025, the remaining exemptions were eliminated. In June 2025, rates doubled to 50%. These rates apply to raw steel mill products (HTS Chapters 72 and 73) and aluminum articles (HTS Chapter 76). Finished goods that contain steel or aluminum — automobiles, machinery, appliances — are generally not classified as "steel articles" under Section 232 unless they are downstream steel products specifically identified in the Section 232 proclamations. The distinction between raw steel (S232-covered) and steel-containing manufactured goods (covered by other authorities) is critical for accurate tariff calculation. For businesses that use steel or aluminum as primary inputs, Section 232 has fundamentally altered cost structures. A steel service center importing hot-rolled coil from Germany at $800/ton pays $400/ton in Section 232 duties — making the effective delivered cost $1,200/ton before freight, MPF, and handling.

Steel articles covered by Section 232 include: hot-rolled coil (HTS 7208), cold-rolled coil (7209), coated steel (7210, 7212), plate (7208-7211), structural shapes (7216), pipe and tube (7304-7306), wire rod (7213), and various semi-finished and finished steel mill products. The coverage is defined by specific HTS subheadings in the Section 232 proclamation annexes. Aluminum articles covered: unwrought aluminum (7601), aluminum waste and scrap (7602), aluminum powders (7603), aluminum bars, rods, profiles (7604), aluminum wire (7605), aluminum plates, sheets, strip, and foil (7606-7607), aluminum tubes and pipes (7608), and aluminum castings and forgings (7616). Primary focus is semi-fabricated aluminum used as industrial inputs. Not covered by S232 (but may face other tariffs): aluminum beverage cans (typically finished product, not "aluminum article"), aluminum-containing finished goods that are not primarily classified as aluminum articles, most downstream manufactured goods containing steel or aluminum as components. Copper was added to Section 232 coverage in March 2025 at 25%, then raised to 50% in June 2025. Covered products include copper cathodes, wire rod, tube, sheet, and other semi-fabricated copper forms. This significantly increased costs for electrical wire manufacturers, plumbing products producers, and heat exchanger manufacturers that use copper as a primary input.

Section 232 products — steel, aluminum, copper, lumber, autos, auto parts, and semiconductors — are explicitly excluded from Section 122 duties. This is commercially significant because it prevents the two major surcharges from stacking. Without this exclusion, a steel importer would pay: MFN ~0.5% + Section 122 15% + Section 232 50% = 65.5%. With the exclusion, they pay: MFN ~0.5% + Section 232 50% = 50.5%. The exclusion saves approximately 15 percentage points — the same amount as Section 122 itself. The exclusion reflects a deliberate policy decision: Section 232 products already bear a significant national security tariff burden designed to achieve specific domestic production outcomes (rebuilding US steel and aluminum capacity). Imposing Section 122 on top would be punitive rather than policy-driven. For importers, this interaction means you cannot simply add S122 to S232 products in your calculations. Section 232-covered products use a different formula: Total Rate = MFN + S232 (not + S122). For Chinese S232 goods, the formula is: Total Rate = MFN + S232 + applicable S301 (for downstream Chinese steel articles, not raw steel). This exclusion does not extend to the July 24 Section 122 expiration — S232 products are unaffected by the expiration because they were never subject to S122 in the first place. Section 232 steel remains at 50% before and after July 24.

Section 232 steel and aluminum tariffs affect not just importers of raw steel and aluminum, but the entire supply chain of industries that use these materials as inputs. Construction: steel structural shapes, rebar, and decking at 50% S232 have increased construction costs by 8–15% for commercial and industrial projects heavily reliant on imported steel. US domestic steel production has not fully met demand, leading to higher domestic steel prices as well as import duties. Automotive: aluminum body panels, frames, and castings for US vehicle production — especially for light-weighting programs — face 50% S232 on imports from Europe and Japan. OEMs have largely absorbed this through US and Canadian aluminum supply, but specialty alloys not produced domestically continue to face the tariff. Appliances: steel for refrigerator cabinets, washing machine drums, and dishwasher interiors has contributed to appliance price increases of 12–20% since 2025. GE Appliances, Whirlpool, and LG Electronics NA have all cited steel costs in earnings guidance. Electrical manufacturing: copper at 50% S232 has increased costs for wire and cable manufacturers, transformer producers, and electrical contractors. US copper production from domestic mines has increased but not eliminated import dependence for specialty grades.

With 50% S232 applying globally (except UK at 25%), sourcing strategies for steel and aluminum must focus on domestic supply, USMCA-qualifying North American production, or accepting the tariff burden. Domestic US production: US steel mills (Nucor, Steel Dynamics, U.S. Steel, AK Steel/Cleveland-Cliffs) have increased capacity in response to S232. Lead times and premiums for domestic steel have increased, but the tariff-free price point may still beat imported steel plus duty for many grades. Canada and Mexico (USMCA): USMCA does not exempt steel and aluminum from S232. This is a critical distinction — USMCA exempts finished goods from tariff surcharges, but steel articles from Canada and Mexico face S232 regardless of USMCA treatment, because steel and aluminum are specifically addressed in the S232 proclamations as not covered by the USMCA carve-out. UK at 25%: the UK's partial S232 exemption (25% vs 50% for other countries) makes UK-origin steel and aluminum relatively more competitive for specialty grades not produced domestically. UK steel producers have increased US-focused marketing for niche products. The exclusion process: companies can apply for product-specific exclusions from S232 if domestic US production of the specific product does not exist at sufficient volume, quality, or competitive price. The exclusion application process through the Commerce Department is detailed and competitive — domestic steel mills can and do object to exclusion requests. Approved exclusions provide significant cost relief but are not guaranteed.