For hardware structural components exported to the US, the 2026 tariff structure consists of three superimposed layers: the MFN (Most-Favored-Nation) base rate, the Section 232 additional tariff, and the Section 301 additional tariff. There is no single answer to “what the US tariff is”—calculations must be performed item-by-item based on specific HTS codes and material compositions.
This article explains the calculation method based on the latest policies.
I.
2026 Section 232 Tariff Policy Update (Steel, Aluminum, and Copper)
Effective April 6, 2026, the US imposed a uniform Section 232 additional tariff on global steel, aluminum, copper, and their derivative products. Following a presidential proclamation on June 1 and implementation on June 8, the policy shifted to a tiered system: bulk steel, aluminum, and copper products remain subject to a 50% tariff; derivative products fall into four tiers—25%, 15%, 10%, and 0%. Specifically, agricultural machinery and stationary industrial machinery/power equipment are subject to a temporary 15% rate (for trade agreement partners, valid until December 31, 2027), while derivative products made entirely from metal smelted or melted within the US qualify for 10% or even 0% rates (to encourage domestic sourcing).
Most hardware structural components (such as stamped parts, fasteners, and pipe fittings) fall under the “derivative products” category; the actual tariff rate depends on which tier applies to the specific tariff code.
II. Practical Rules: How MFN and Section 232 Duties Combine
According to CBP guidelines: For goods with a base MFN rate below 10%, the Section 232 additional duty brings the total tariff to 10% (e.g., MFN 3.4% → Total 10%); for goods with an MFN rate between 10% and 15%, the total tariff is set at 15% (applying the preferential tier for agricultural/industrial equipment); for goods with an MFN rate of 15% or higher, the Section 232 additional duty is 0%, and only the MFN rate applies. Example: Steel fasteners (HTS 7318) have an MFN rate of approximately 3.4%;
under the “derivative products + low MFN” rule, the total tariff becomes 10% after adding the Section 232 duty (excluding Section 301 duties).
III.
Don’t Forget Section 301 Tariffs (China-Origin)
Hardware products originating in China are also subject to US Section 301 tariffs: effective July 24, 2026, Section 301 tariffs are adjusted to two tiers—10% and 12.5% (replacing the previous uniform 10% rate).
Taking Chinese-exported 7318 fasteners as an example, the total tax burden is: MFN 3.4% + Section 232 adjustment to 10% + Section 301 duty of approximately 10%–12.5%, resulting in a combined rate exceeding 20%—meaning price quotes must account for these cumulative layers.
Steel and aluminum products originating in the EU are subject to a 15% tariff cap under the US-EU agreement (effective July 1, 2026).
IV. How to Check Tax Rates for Your Products
First, use the USITC HTS online search tool (hts.usitc.gov) to look up MFN General rates and “Free” status based on the 10-digit code (e.g., 4.8% for pipe fittings under 7307; check subheadings for iron/steel articles under 7326.90). Second, consult CBP CSMS notices and the Federal Register: the Section 232 regulations (91 FR 18201) and the June 8, 2026 adjustment guidelines contain comprehensive lists of affected tariff codes; coverage is extensive for Chapter 73 (iron/steel articles) and Chapters 82, 83, and 84 (derivatives), so verify your specific codes item by item. Third, request a tariff estimate from your customs broker: provide the HS code, material composition, and country of origin to obtain the combined tariff rate (MFN + Section 232 + Section 301) and the landed cost. Note that once the *de minimis* exemption (for shipments under $800) is eliminated in August 2025, small packages will also be subject to standard tariff declaration requirements.
V.
Strategies for Response
First, base price quotes on the combined tariff rate and build in a buffer for potential tariff fluctuations.
Second, monitor exemptions and preferential rates—such as the 10%/0% tiers for derivatives made from US-smelted metal, the 15% cap for the EU, and the 15% tier for industrial equipment from trade agreement partners—and evaluate whether to adjust your supply chain layout accordingly. Third, consider the risk of reciprocal countermeasures: US-China tariff dynamics are constantly shifting, so include a clause in export contracts stating that “prices are subject to renegotiation/review in the event of tariff adjustments.” Fourth, ensure compliance for small orders: following the removal of the $800 exemption, process samples and small orders through formal customs declaration procedures.
Industry experts advise treating US tariffs as a “moving target”—verify current rates using HTS and CSMS data before every shipment rather than relying on figures quoted three months prior.
