9903.85.21—Section 232 Aluminum
Overlay rate
The duty provided in the applicable subheading + 10%
Stacks on top of the base HTSUS rate of the product
Tandom · Duty calculator
See this overlay in a real duty stack
Pick a covered 10-digit code below, plug in country and invoice value, and Tandom will compute the full landed cost with this overlay stacked on the base rate.
Plain-English explanation
HTS 9903.85.21 is a Chapter 99 aluminum derivative tariff modification under Section 232 Aluminum. When a base 10-digit code falls within this provision's scope, it imposes the duty provided in the applicable subheading + 10% on top of the underlying base duty. It applies only to imports from CA. It has been in effect since 2020-09-01 with no expiration on file. It currently covers 65 base HTS codes in Tandom's catalog.
Rate stack at entry
Description
Authoritative scope text from the U.S. Harmonized Tariff Schedule
Aluminum products of Canada enumerated in U.S. note 19(a)(iv) to this subchapter
How to use this provision
When and how this overlay shows up at entry
Chapter 99 provision 9903.85.21 is a tariff modification — it doesn't classify a product on its own. When a base 10-digit HTS code falls within this provision's scope and a shipment matches the country and date conditions, the broker declares the base code at entry, then references 9903.85.21 on a separate line so its rate stacks on top.
Worked example
How this overlay applies to a real covered code
Imagine an importer files a $10,000.00 shipment of 7601.10.30.00 (of uniform cross section throughout its length, the least cross-sectional dimension of which is not greater than 9.5 mm, in coils) from a country in scope. The overlay rate of The duty provided in the applicable subheading + 10% stacks on top of the base HTSUS rate of 2.6%.
Base duty
$260.00
2.6% × $10,000.00
This overlay
$1,000.00
10% × $10,000.00
Total duty
$1,260.00
Plus AD/CVD if applicable
Opens the Tandom calculator with HTS 7601.10.30.00 and $10,000.00 pre-filled — add a country to compute the full landed cost.
Target countries
Applies only to imports from these countries
Affected base HTS codes(65)
Showing the first 50 of 65 covered codes (alphabetical).
7601.10.30.00Of uniform cross section throughout its length, the least cross-sectional dimension of which is not greater than 9.5 mm, in coils2.6%7601.10.60.40Of 99.9 percent aluminum or greaterFree7601.10.60.45Of greater than 99.8 percent but less than 99.9 percentFree7601.10.60.90OtherFree7601.20.30.00Of uniform cross section throughout its length, the least cross-sectional dimension of which is not greater than 9.5 mm, in coils2.6%7601.20.60.00Containing 25 percent or more by weight of siliconRelated Chapter 99 codes(24)
Other Section 232 Aluminum provisions in Tandom's catalog
9903.40.05Radial tires of a kind used on motor cars (other than racing cars), station wagons, sport utility vehicles, vans and on-the-highway light trucks (provided for in subheading 4011.10.10 or 4011.20.10)9903.40.10Other tires of a kind used on motor cars (other than racing cars), station wagons, sport utility vehicles, vans and on-the-highway light trucks (provided for in subheading 4011.10.50 or 4011.20.50)9903.74.01Medium- and heavy-duty vehicles as provided for in subdivision (b) of U.S. note 38 to this subchapter.9903.74.02Buses and other vehicles classified in HTSUS heading 8702 as provided for in subdivision (c) of U.S. note 38 to this subchapter.9903.74.03Medium- and heavy-duty vehicles, as provided for in subdivision (d) of U.S. note 38 to this subchapter.Frequently asked questions
What is HTS 9903.85.21?
HTS 9903.85.21 is a Chapter 99 tariff modification under Section 232 Aluminum. It is not a product classification — it's an overlay code that stacks on top of a base 10-digit HTS code at entry. Scope text: Aluminum products of Canada enumerated in U.S. note 19(a)(iv) to this subchapter
What rate does HTS 9903.85.21 apply?
The provision states: "The duty provided in the applicable subheading + 10%" That rate stacks on top of whatever the base HTSUS rate is for the underlying 10-digit code. Use the Tandom calculator to compute the full landed cost for any covered product.
Which countries does HTS 9903.85.21 apply to?
9903.85.21 applies only to imports from: CA.
Is HTS 9903.85.21 currently active?
Yes — 9903.85.21 is currently active (effective 2020-09-01) with no expiration on file.
Learn more
Tandom guides relevant to this code
How Chapter 99 tariff layers stack on a single entry
How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
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How to calculate US import duties
A working guide to the inputs, the layers, and the math behind a US entry summary in 2026. Written for brokers, forwarders, and importer compliance teams.
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