How do you work out the Section 232 duty on a derivative line: tier, base and cap?

Which Section 232 heading does a metal or derivative line take?

Since April 6, 2026, every Section 232 metals line on a Form 7501 carries one heading from the range 9903.82.01 to 9903.82.26. U.S. note 16(a) to subchapter III of chapter 99 makes those headings mutually exclusive: an article takes no more than one of them. The heading carries both the tier and, by its description, the reason for the tier. This table is the map as printed in HTSUS 2026 Revision 23, the revision current on November 11, 2026.

Russian aluminum stays apart from this map. Clause (8) of Proclamation 11021 keeps the 200 percent duty of Proclamation 10522 on aluminum articles and derivatives that are products of Russia or contain any primary aluminum smelted in Russia, or that were cast in Russia, reported under 9903.85.67 and 9903.85.68. CSMS # 68253075 adds that those lines may not be reported under 9903.82.03.

What changed on April 6 and June 8, 2026?

Two proclamations set the current method, and the entry date decides which applies.

• April 6, 2026. Proclamation 11021 (signed April 2, 2026, 91 FR 18201) applies the Section 232 duty to the full customs value of the imported product, regardless of metal content, for goods entered or withdrawn from warehouse for consumption on or after 12:01 a.m. EDT on April 6, 2026 (clause (1)). It sets 50 percent for the products in its Annex I-A (clause (2)), 25 percent for the products in Annex I-B (clause (3)), and the 15 percent all-in treatment for Annex III until 11:59 p.m. EST on December 31, 2027 (clause (5)). Its Annex IV wrote the new U.S. note 16 and the headings.
• June 8, 2026. Proclamation 11032 (signed June 1, 2026, 91 FR 34085) added list (c)(xi) and headings up to 9903.82.26 for goods entered on or after 12:01 a.m. EDT on June 8, 2026. It set 25 percent for that list, a 15 percent total for products of Argentina, Ecuador, El Salvador, Guatemala, Japan, Korea, Liechtenstein, Switzerland, Taiwan, the United Kingdom and EU member states, and a USMCA rule that charges 25 percent only on non-US content with a floor of 15 percent. It also lowered the US-metal threshold from 95 to 85 percent of the metal's weight (clause (4)).
• Technical corrections. CSMS # 68554727 (May 6, 2026) announced heading 9903.82.01 for listed articles with no aluminum, steel or copper, retroactive to entries from April 6, 2026, and confirmed that UK steel melted and poured in the Netherlands by Tata Steel UK may use the UK headings until January 1, 2028.

Entries before April 6, 2026 used the earlier headings and, for most derivatives, the value of the metal content on its own line. That is a different calculation, covered in Section 232 on full value since April 6, 2026. This page is the method for entries from April 6.

How do you get from an HTS number and an entry date to the duty?

Work through these steps in order. Each one can end the calculation.

1. Fix the entry date. Entries from April 6, 2026 follow note 16 as written by Proclamation 11021; entries from June 8, 2026 also have list (c)(xi), headings 9903.82.20 to 9903.82.26 and the 85 percent US-metal threshold. Annex III treatment (lists (c)(ix) and (x)) runs until December 31, 2027; from January 1, 2028, clause (7) of Proclamation 11021 moves those articles to the 25 percent rates, and CSMS # 68253075 says headings 9903.82.07, .08, .10, .11 and .12 stop applying then.
2. Find the HTS number on the lists. Note 16(c) lists HTS numbers at 4, 6, 8 or 10 digits. Match at the most specific level printed. A list can name some statistical suffixes under a subheading and not others: list (c)(vii) names 8482.10.5052 and 8482.10.5056 but not 8482.10.5044 or 8482.10.5048, so the 10-digit number matters. A number on no list takes no 9903.82 heading.
3. Check for metal at all. A listed article with no aluminum, steel or copper takes 9903.82.01 and no duty.
4. Apply the weight test outside chapters 72, 73, 74 and 76. Under note 16(c), the duty headings apply only where the weight of the applicable metal is at least 15 percent of the article's weight; the list title names the metal, and an article on two lists uses the aggregate weight. CSMS # 68253075 gives the example of 8302.10.60, which sits on lists (c)(vi) and (vii), so both its aluminum and its steel count, but not its copper. Below 15 percent, the line takes 9903.82.03 and reports the metal weight in kilograms.
5. Check origin and where the metal was made. Russian products and products of general note 3(b) countries take their own headings. UK products take 9903.82.04 or .05 only if at least 95 percent of the steel was melted and poured, or the aluminum smelted or most recently cast, in the United Kingdom (note 16(d)). Derivatives whose metal was at least 85 percent US-melted or US-smelted (95 percent before June 8, 2026) take the US-metal headings under note 16(e). These depend on the melt-and-pour and smelt-and-cast countries reported on the line, which melt-and-pour reporting on past entries covers.
6. Read the tier from the list. 50 percent, 25 percent, or the 15 percent total, as in the table above.
7. Apply it to the full customs value. The base is the entered value of the whole line, not the metal content.
8. Add the other layers on their own terms. The metals duty is charged once even if the article contains two or three metals (clause (9)). It sits on top of any trade-agreement rate (note 16(b)). It switches off the Section 301 forced-labor duties on lines in 9903.82.02 and 9903.82.04 to .26, which report 9903.05.90 (note 52(f)(1)). China Section 301 duties and antidumping and countervailing duties still apply. Why your entry shows the wrong duty stack sets the other layers out by date.

What is the 15 percent cap, exactly?

For lists (c)(ix) and (x), note 16(f) does not add a fixed 15 percent. It makes 15 percent the total of the column 1 rate and the Section 232 duty. An article with a free column 1 rate pays 15 percent; one at 4 percent pays 11 percent more; one at 15 percent or above takes 9903.82.11 and pays nothing more. The US-metal version under note 16(e) works the same way at 10 percent (9903.82.07 below 10 percent, 9903.82.08 at or above). Proclamation 11032 gave list (c)(xi) products of the listed partners the same kind of 15 percent total under 9903.82.22.

So "cap" is a fair word for the buyer of a high-duty article and a misleading one for a free article, which pays the full 15 percent. The common error is to read the heading's 15 percent as an add-on and charge it on top of the column 1 rate. On an article with a 4 percent rate that overpays 4 percent of the value on every line.

Worked lines: three derivatives, one entry date

Three lines, all products of Germany, entered on September 15, 2026, each with an entered value of $40,000. No antidumping or countervailing duty order is assumed. Column 1 rates are from HTSUS 2026 Revision 23; fees are left out. Because each line takes a heading in the 9903.82.02 or 9903.82.04 to .26 range, the Section 301 forced-labor headings do not apply (note 52(f)(1)), and the Section 122 surcharge window had ended before this entry date.

The arithmetic: the bolts pay 8.5% × $40,000 = $3,400 plus 50% × $40,000 = $20,000. The bearings pay 9% × $40,000 = $3,600 plus 25% × $40,000 = $10,000. The plows pay 15% total less a 0% column 1 rate, so 15% × $40,000 = $6,000.

Now change one fact on each line and the duty moves:

• If at least 85 percent of the plows' steel had been melted and poured in the United States, note 16(e) moves them to 9903.82.07 at a 10 percent total: $4,000, a difference of $2,000.
• If the bearings were products of the United Kingdom made from steel at least 95 percent melted and poured in the United Kingdom, heading 9903.82.05 applies at + 15 percent: $6,000 of Section 232 duty instead of $10,000.
• If the bearings had been entered on March 30, 2026, the April 6 full-value rule would not apply, and the old content-value method would govern the line.

Where does this go wrong on real entries?

The errors seen in practice are rarely the rate. They are in the steps before it:

• The 15 percent total charged as an add-on on list (c)(ix) and (x) articles with a positive column 1 rate: an overpayment equal to the column 1 rate.
• A 10-digit number off the list reported under 9903.82.09 because its 8-digit parent is listed: an overpayment of the whole Section 232 duty.
• A light article reported at full tier when the applicable metal is under 15 percent of its weight, with no weight record behind the heading choice, or the reverse, 9903.82.03 claimed without a weight calculation to back it.
• UK or US-metal headings claimed without melt evidence. Each depends on the melt-and-pour or smelt-and-cast countries on the line and on mill certificates in the file. A claim that cannot be supported is an underpayment.
• A Section 301 forced-labor line still reported on a 9903.82.02 or 9903.82.04 to .26 line entered from July 24, 2026, instead of 9903.05.90.
• Content value kept after April 6 or full value used before it. The sibling page on the April 6 change has the before-and-after.

Each error has a direction. An overpaid line is recovered by post-summary correction before liquidation or protest after it; an underpaid one is corrected the same way or through a prior disclosure. How long to fix a past entry has the clocks.

How do you check a year of lines at once?

Pull the line-level entry summary data for the period: HTS number, Chapter 99 numbers, country of origin, melt-and-pour and smelt-and-cast countries, entered value, second quantities and entry date. Then run each line through the steps above against the note 16 lists in force on its own entry date. TariffSense reads Form 7501 lines from broker entry exports and spreadsheets, works out which 9903.82 heading the HTS number, origin, metal countries and entry date point to, and flags each line where the heading, the base or the rate differs from what was filed, in either direction. For a single line, the duty calculator shows the stack for a given HTS number, origin and date.

Two dates are worth watching. The Commerce notice of August 6, 2026 (91 FR 50756) proposed adding 14 more derivative articles, including aluminum powder, fire extinguishers, floor safes, and tanker and other trailers; until a final notice is published they are not on the lists. And the 15 percent totals for Annex III (lists (c)(ix) and (x)) and for list (c)(xi) partner products end at 11:59 p.m. EST on December 31, 2027, when clause (7) of Proclamation 11021 and clause (3) of Proclamation 11032 move those articles to the 25 percent rates, so the same plow entered on January 3, 2028 is priced under a different heading.

This page describes the law; it is not legal advice. For a filing, confirm the heading with a licensed customs broker, and with counsel where a correction or disclosure is involved.