Section 232 Tariff Expansion: What It Means for Manufacturers Beyond Steel
In this article, learn about:
How the April 2026 proclamation changed the way Section 232 duties are calculated
Which finished goods the derivative list already covers, and which 14 categories are still pending
How procurement and supply chain teams are treating tariff exposure
For many manufacturers, Section 232 of the Trade Expansion Act of 1962, a statute that allows tariffs on imports the government treats as a national security risk, was never a major concern. It used to apply to raw steel and aluminum arriving by the ton, so a company purchasing finished parts or imported machinery had little reason to track it.
But that changed in 2026. In April, a presidential proclamation rewrote how the duty is calculated. Additionally, in August, the Bureau of Industry and Security (BIS) proposed adding 14 more product categories to a derivative list that already covers hundreds of finished goods. For a procurement or supply chain team, the practical questions are now which products carry exposure and what can be done about it.
What Changed Under Section 232 in 2026?
The April 2, 2026 proclamation, which took effect on April 6, raised rates and applied the duty to the entire customs value of covered articles and their derivatives, no matter how much metal they hold. Goods classified under chapter 72 and most of chapters 73, 74, and 76 now carry 50 percent on full value, while derivative articles that are more than 15 percent covered metal now carry 25 percent on full value. Additionally, derivatives made entirely with U.S.-smelted, cast, or poured metal qualify for a 10 percent rate.
Four months later, BIS published a Federal Register notice requesting comment on additional derivative categories. The proposed list includes:
Aluminum powder
Parts of welding machines
Floor safes
Certain electric conductor cables
Fire extinguishers
Parts of heat exchange units
Parts of hydraulic engines and motors
Self-propelled cranes and straddle carriers
Tanker trailers
Agricultural self-loading trailers
Most would be taxed at 25 percent if added, though a few fall under rates set by earlier proclamations.
The comment window for the August proposal closed on August 27, 2026. As of mid-October, there is no final decision and no effective date, and the decision has yet to be made by the Secretary of Commerce and the U.S. Trade Representative.
Since April, tariff rates have moved in both directions. A June 1 proclamation cut the rate from 25 to 15 percent on select farm and construction equipment from June 8, 2026 through December 31, 2027. It also set a 10 percent rate for imported capital equipment built mostly from U.S. metal.
Stage | What it covered | How the duty was calculated |
Original scope | Raw steel and aluminum articles | Duty on the imported metal itself |
April 2026 proclamation | Metal articles plus a long derivative list | Full customs value of the finished good, at 50, 25, or 10 percent by category |
August 2026 proposal | 14 more derivative categories, pending | Full customs value, most proposed at 25 percent |
Why Does Full Customs Value Change the Math So Much?
Before April, a customs broker split the declared value of a derivative product into metal content versus everything else, and the duty applied only to the metal share. A bracket or a housing, for instance, was only taxed on the steel inside it, so the cost stayed small next to the value of the part.
The duty now applies to the declared value of the whole article.
Consider a piece of imported equipment with a customs value of $80,000, with roughly $6,000 of steel content. Under the older method, a 25 percent duty applied to just the portion of metal came to about $1,500. Under the current method, the same 25 percent applies to the full $80,000 value, which comes to a $20,000 tax. The product, the supplier, and the metal content stay the same, but the duty balloons to more than thirteen times larger.
That increase is why the expansion reaches companies with no Section 232 history. A costly finished good with little metal in it now carries a tariff bill calculated on its full price rather than its metal content, and that is much harder to bury in landed cost.
Section 232 Derivative Products, by the Numbers
The list of derivative products grew sharply before this year’s August proposal.
In August 2025, Commerce added more than 400 Harmonized Tariff Schedule subheadings to the steel and aluminum derivative lists, effective August 18 that year. Published counts differ, at 407 or 428, based on how the inclusions are tallied.
That round added:
Consumer goods
Household products
Industrial products
Transportation products
Some chemical and energy products
Infrastructure products.
Fasteners, wire products, tubular parts, and downstream assemblies are all on the list.
A manufacturer that imports finished furniture parts, vehicle parts, or shop equipment may now have Section 232 exposure across several product lines, without ever having bought a ton of steel. Now, classification drives exposure, not just metal content.
How Are Sourcing Decisions Affected by the Section 232 Tariff Expansion?
A 25 percent duty on full customs value is large enough to change which supplier is cheapest, which production site is viable, and which product line still clears its margin target. The 10 percent rate for goods made with U.S. metal and the temporary 15 percent rate on farm and construction equipment are sourcing levers. Using either one means knowing where a supplier’s metal is smelted and poured, which is supplier data rather than customs data.
In addition, the timing matters. With the 14 proposed categories still pending as of October 2026, a manufacturer whose products sit on that list has a window to qualify other suppliers before any effective date arrives. Companies that wait for the final notice will face time pressure in making a final decision.
How Are Manufacturers Mapping Tariff Exposure?
Teams working through this tend to follow a similar sequence.
Every imported good and part is matched against the current derivative subheadings, including the 14 proposed ones, so exposure is known before a rule lands.
Each affected item is repriced at full customs value, which shows the product lines that can absorb the duty and the ones that no longer clear margin.
Metal origin is double-checked with suppliers, since the 10 percent rate rests on U.S.-smelted, cast, or poured inputs that most supplier records do not capture.
Tariff changes are built into forecasting and planning as a standing input, due to the list changing several times in two years.
Frequently Asked Questions
Are the 14 proposed derivative categories subject to tariffs today?
No. BIS requested public comment on the proposal, the comment period closed on August 27, 2026, and no duties have been imposed on those categories. The notice set no effective date and no decision date.
How are the steel and aluminum tariffs in 2026 different from earlier rounds?
The rates are higher and the duty base is wider. The biggest change is that duties now apply to the full customs value of a covered article, not to its metal content alone.
Does a product with very little metal still face the full duty?
Yes, if its subheading is on the derivative list. Derivative articles that are more than 15 percent covered metal carry 25 percent on the entire customs value of the article.
Is there any lower rate available?
Derivatives made entirely with U.S.-smelted, cast, or poured metal qualify for a 10 percent rate. Select farm and construction equipment carries a temporary 15 percent rate through December 31, 2027.
Want To See How Supplier Data Holds Up When Sourcing Changes?
A sourcing shift creates paperwork downstream. Reclassified goods, new suppliers, and revised landed costs all have to show up correctly in the purchase orders, shipment notices, and invoices sent to retail partners. Most of that exchange runs on electronic data interchange (EDI). SPS Commerce Fulfillment and EDI handles it across the trading partner network, so a change in the supply base does not become a data problem. The sourcing decision stays with the manufacturer, and SPS keeps the record of it accurate.
Not ready for that conversation? The Supply Chain Source has free resources on supplier onboarding, order accuracy, and planning.
This article is general information about trade policy developments and is not legal, customs, or tariff classification advice. Consult qualified trade counsel or a licensed customs broker about your specific products and classifications.