9903.79.01 Semiconductors 232 Tariff: Rate, Scope, and Stacking

Key Points

• HTS 9903.79.01 imposes an additional 25% Section 232 duty on covered semiconductor articles, stacked on top of the normal column 1 rate, effective January 15, 2026, with no announced end date.
• Three 6-digit subheadings are in scope: 8471.50, 8471.80, and 8473.30, as defined in U.S. note 39(a) and (b) to subchapter III of Chapter 99.
• The legal authority is Proclamation 11002, published at 91 FR 2443; CBP implementation guidance is in CSMS message 67400472.
• Exclusion and exception headings 9903.79.02 through 9903.79.09 exist under U.S. note 39 and are non-duty-bearing; confirm eligibility before claiming one.
• 9903.79.01 is entered as a Chapter 99 overlay line alongside the underlying Chapter 1-97 classification on every covered entry.

On this page

1. What 9903.79.01 is and which program created it
2. Covered products and HTS subheadings
3. The 25% rate and how it stacks
4. Exclusions under 9903.79.02 through 9903.79.09
5. How 9903.79.01 appears on a customs entry
6. What importers should do
7. Key references

9903.79.01 is the Chapter 99 duty heading for the Section 232 semiconductors program. It adds 25% to the normal column 1 rate on semiconductor articles classified under HTS subheadings 8471.50, 8471.80, and 8473.30. The tariff took effect January 15, 2026, and carries no announced expiration date, as of August 12, 2026. Every importer moving goods under those three subheadings must assess whether 9903.79.01 applies and budget accordingly.

The links in this article go to the primary documents: the proclamation, Federal Register notice, and official tariff schedule pages themselves. Read the source.

What 9903.79.01 is and which program created it

9903.79.01 was established under the Section 232 national-security tariff authority to address imports of semiconductor articles. The legal foundation is Proclamation 11002, published in the Federal Register at 91 FR 2443. The code sits in Chapter 99, Subchapter III of the Harmonized Tariff Schedule of the United States, the standard location for trade-remedy and national-security overlay duties.

The official heading text reads: Semiconductor articles as provided for in subdivisions (a) and (b) of U.S. note 39 to this subchapter. That cross-reference to U.S. note 39 is the controlling product-scope document. The note defines both the covered classifications (subdivision (a)) and any qualifying conditions (subdivision (b)).

Covered products and HTS subheadings

As of the January 15, 2026 effective date, three 6-digit subheadings are covered by U.S. note 39(a)/(b):

• 8471.50 - processing units and certain data-processing equipment
• 8471.80 - other data-processing units and equipment
• 8473.30 - parts and accessories for the machines of heading 8471

Coverage is defined at the 6-digit subheading level. The scope rules attach at 6-digit grain, meaning every 8-digit or 10-digit HTS number that rolls up to 8471.50, 8471.80, or 8473.30 falls within the program unless a valid exclusion applies. Confirm the exact 10-digit classification of your goods against the Harmonized Tariff Schedule at hts.usitc.gov and verify current scope with your broker, because the HTS is updated on a rolling basis.

No country-specific exemptions appear in the facts for this code. The program, as structured, applies to all countries of origin unless a specific exclusion heading is claimed. Confirm the current country scope in the HTSUS or with your broker.

The 25% rate and how it stacks

The HTSUS general column rate for 9903.79.01 is: the duty provided in the applicable subheading + 25%. In practice, that means you add the normal column 1 general rate for the underlying 8471.50, 8471.80, or 8473.30 subheading and then add 25 percentage points on top of the dutiable value.

Stacking with other trade-remedy duties

Goods subject to 9903.79.01 may also be subject to other Section 301 or other Chapter 99 overlay duties depending on country of origin and product classification. The Section 232 semiconductor duty stacks additively with those other measures unless a specific provision in the HTSUS or an applicable U.S. note states otherwise. Check the current schedule and CBP guidance to identify every overlay that applies to your entry. For a related example of how Section 232 overlays interact with entry-filing requirements, see our article on the Section 232 Polysilicon Tariff and ACE CATAIR Entry Type 13 Updates.

Use a duty calculator to model total landed cost before placing orders. Our duty calculator can help you run that math quickly.

Exclusions under 9903.79.02 through 9903.79.09

Headings 9903.79.02 through 9903.79.09 are the exclusion and exception headings established under U.S. note 39. These headings are non-duty-bearing: they do not impose additional duty. Instead, claiming one of these headings removes the 25% overlay for qualifying goods. They are exclusions from the Section 232 semiconductor duty, not additional tariffs.

To claim an exclusion, the imported article must qualify under the terms of the relevant subdivision of U.S. note 39. Confirm the eligibility criteria directly in the HTSUS text at hts.usitc.gov and review any CBP guidance issued via cbp.gov or CSMS. Misclassifying an exclusion heading on an entry that does not qualify exposes the importer to potential underpayment liability.

How 9903.79.01 appears on a customs entry

Chapter 99 overlay codes work as a second line on the entry summary. Every covered shipment requires two HTS lines reported to CBP's Automated Commercial Environment (ACE):

1. The underlying Chapter 1-97 classification (for example, a specific 10-digit number under 8471.50, 8471.80, or 8473.30) with its normal column 1 rate.
2. 9903.79.01 as the overlay line, triggering the additional 25%.

If an exclusion applies, the exclusion heading (9903.79.02 through 9903.79.09) replaces 9903.79.01 on the overlay line. The underlying Chapter 1-97 line is still required. CBP's CSMS message 67400472 provides the operational implementation guidance for this program. Confirm current ACE reporting requirements with your broker before filing.

Importers who need a broader orientation to Chapter 99 overlay codes and how they interact with standard classifications can consult our 2026 tariff code overview.

What importers should do

• Audit your classifications now. Pull every active SKU classified under 8471.50, 8471.80, or 8473.30 and confirm the 10-digit number against the current HTSUS at hts.usitc.gov. The scope rules attach at the 6-digit level, so every 10-digit number under those three subheadings is presumptively subject to 9903.79.01.
• Evaluate exclusion eligibility. Review U.S. note 39 in full to determine whether any of headings 9903.79.02 through 9903.79.09 apply to your specific goods. Do not claim an exclusion without confirming the qualifying conditions in the HTSUS text.
• Model your total landed cost. Stack the column 1 rate, the 25% Section 232 overlay, and any other applicable Chapter 99 duties for your country of origin. Use the duty calculator to quantify the impact on each product line.
• Brief your broker and review entry procedures. Ensure your customs broker is reporting 9903.79.01 on every covered entry and has reviewed CSMS 67400472. Importer oversight of broker filings is your responsibility. For guidance on that obligation, see our article on Customs Broker Oversight as an Importer Duty.

Key references

• Proclamation 11002 - White House proclamation establishing the Section 232 semiconductor tariff program
• 91 FR 2443 - Federal Register publication of Proclamation 11002
• Harmonized Tariff Schedule of the United States (hts.usitc.gov) - Current HTSUS text including Chapter 99, U.S. note 39, and subheadings 8471.50, 8471.80, and 8473.30
• CBP CSMS 67400472 - CBP operational guidance on the Section 232 semiconductor program implementation
• Section 232 Polysilicon Tariff and ACE CATAIR Entry Type 13 Updates - Related article on Section 232 entry-filing mechanics