Section 232 tariff calculator for aluminum parts

Estimate what an aluminum part made in Mexico pays when it enters the United States. Since April 6, 2026, Section 232 charges 50% or 25% of the full customs value depending on the annex of the tariff line (Proclamation 11021), 10% if the aluminum was smelted and cast in the United States (Proclamation 11032) and 200% if the country of smelt or cast is reported as unknown (CBP, CSMS 65340246). Enter the value, the annex and the origin of the metal to get the estimated duty, the value with duty and the documents CBP expects. Rates as of October 26, 2026.

Customs value of the part or shipment USD

The value declared at entry, usually the purchase price. Since April 6, 2026, Section 232 is charged on this full value, not only on the aluminum (Proclamation 11021, clause 1).

Annex of the HTSUS line

Aluminum articles are sheet, plate, bar, extrusions, wire, tubes, castings and forgings (Proclamation 9704). Your licensed customs broker confirms the annex from the 10-digit HTSUS line; CBP lists the Chapter 99 headings in CSMS 68253075 and 68855869.

Country of smelt and cast of the aluminum

You report the primary and secondary country of smelt and the country of cast on each line (CBP, CSMS 55424218). US metal counts when at least 85% of the aluminum by weight was smelted and cast in the United States (Proclamation 11032).

Is the HTSUS line in chapter 72, 73, 74 or 76?

Outside those chapters, a part whose covered metal is under 15% of its weight does not pay this Section 232 (CBP, CSMS 68253075, Apr 3, 2026). Enter both weights in the same unit.

How the duty is calculated

Duty = full customs value × annex rate: 50% for aluminum articles and Annex I-A derivatives, 25% for Annex I-B derivatives (Proclamation 11021 of April 2, 2026, clauses 1 to 3, since April 6, 2026).
Annex I-C goods that qualify under USMCA: duty = 25% × (value − US content), with a floor of 15% of value (Proclamation 11032, clause 2(d), June 8, 2026 to December 31, 2027).
Annex III: rate = 15% − regular duty of the line, or zero if regular duty is already 15% or more (Proclamation 11021, clause 5; Proclamation 11032; until December 31, 2027).
Aluminum smelted and cast in the United States, at least 85% by weight: 10% (Proclamation 11032, clause 4, since June 8, 2026).
Country of smelt or cast reported as unknown: 200%, the rate for Russian aluminum (CBP, CSMS 65340246, since June 28, 2025). Aluminum smelted or cast in Russia: 200% (Proclamation 10522; Proclamation 11021, clause 8).
Outside chapters 72, 73, 74 and 76, if the covered metal is under 15% of the weight: 0% (CBP, CSMS 68253075, April 3, 2026).
Value plus duty = customs value + Section 232 duty. Effective rate = duty ÷ value.

Example with round numbers: an Annex I-B part with a customs value of $10,000 pays $2,500 of Section 232 duty, whether it is 30% or 90% aluminum; in Annex I-A it would pay $5,000. With the country of smelt reported as unknown, it would pay $20,000.

Why doesn't the calculator ask for the value of the aluminum in the part?

Because since April 6, 2026, Section 232 is charged on the full customs value of the product, regardless of its metal content (Proclamation 11021, clause 1). Until then, derivatives generally paid on the value of their aluminum content (Proclamation 10947 of June 3, 2025). The weight of the metal now matters only for the 15% weight exception and the 85% threshold for US aluminum.

What documents CBP expects

On each entry line, the importer reports the primary country of smelt, the secondary country of smelt if any, and the country of cast of the aluminum (CBP, CSMS 55424218 of March 9, 2023; CSMS 68253075 of April 3, 2026). Those countries come from your Mexican supplier's aluminum documents, lot by lot:

Document	What it is for
Mill test report for the lot	Alloy, temper, chemical composition and mechanical properties; ties the part to a lot of material
Mill statement	Where the metal was cast and rolled, which is the country of cast
Country of smelt support	Certificates from the primary ingot producer
Lot traceability	The path from the cast to the coil, sheet or circle used for the part

Almexa casts and rolls its metal at its plant in Cuautitlán Izcalli, Mexico, so the country of cast of its coil, sheet, circles and blanks is Mexico. The primary country of smelt is backed by the certificates of the primary ingot producer, which Almexa buys already imported into Mexico from traders.

Section 232 aluminum tariffs, October 2026 rates in force, derivatives, smelt and cast reporting and key dates, with official sources
How to document the country of smelt and cast the documents behind each declaration
Almexa aluminum origin what Almexa documents per lot
USMCA aluminum coil and sheet from Mexico what Almexa ships to US buyers
Request a quote ask for the material with the lot origin documents

Official sources

Proclamation 10522 of February 24, 2023, 88 FR 13267 200% on aluminum of Russia or with Russian smelt or cast.
Proclamation 10947 of June 3, 2025, 90 FR 24199 50% from June 4, 2025.
Proclamation 11021 of April 2, 2026, 91 FR 18201 full customs value and annexes, from April 6, 2026.
Proclamation 11032 of June 1, 2026, 91 FR 34085 Annex I-C, USMCA non-US content and the 85% threshold, from June 8, 2026.
Bureau of Industry and Security, guidance on "U.S. content", 91 FR 65162, October 14, 2026 USMCA goods in Annex I-C, from October 14, 2026.
CBP, CSMS 55424218, March 9, 2023 definitions of country of smelt and country of cast.
CBP, CSMS 65340246, June 13, 2025 unknown smelt or cast on derivatives charged at 200%, from June 28, 2025.
CBP, CSMS 68253075, April 3, 2026 filing guidance for Proclamation 11021; smelt and cast reporting continues.
CBP, CSMS 68855869, June 5, 2026 filing guidance for Proclamation 11032, including the USMCA two-line entry.
19 CFR part 361, Aluminum Import Monitoring and Analysis System (eCFR) aluminum import license; consulted October 22, 2026.

Frequently asked questions

How do I calculate the Section 232 duty on an aluminum part?

Multiply the full customs value of the part by the rate of its annex: 50% for Annex I-A and aluminum articles and 25% for Annex I-B, since April 6, 2026 (Proclamation 11021). This Section 232 tariff calculator for aluminum parts also applies the rules for Annex I-C, Annex III, US-smelted aluminum and unknown country of smelt.

How much Section 232 duty does a $10,000 aluminum part from Mexico pay?

$2,500 if it is in Annex I-B and $5,000 if it is in Annex I-A, whether it is 30% or 90% aluminum, because since April 6, 2026 the duty is charged on the full value (Proclamation 11021). If the country of smelt or cast is reported as unknown, $20,000 (CBP, CSMS 65340246).

What if my Mexican supplier can't document the country of smelt and cast?

If you report it as unknown, a derivative pays 200%, the rate for Russian aluminum, since June 28, 2025 (CBP, CSMS 65340246). For a part that would pay 25%, the duty is eight times higher; for one at 50%, four times higher. The Commerce aluminum import license does not accept unknown either (19 CFR 361.103).

Does USMCA lower Section 232 on parts made in Mexico?

Only for mobile industrial equipment and machinery in Annex I-C that qualifies under USMCA: from June 8, 2026 to December 31, 2027 it pays 25% on its non-US content, with a 15% floor (Proclamation 11032). Other parts pay the rate of their annex even when they qualify under USMCA.

What documents should I ask my Mexican aluminum supplier for?

The mill test report of the lot, a mill statement of where the metal was cast, the primary ingot producer's certificates that back the country of smelt, and lot traceability. With them you report the three countries without leaving any as unknown.

Need lot documents for a Section 232 entry? Ask for them with your quote.

Request a quote