9903.91.08 Explained: Section 301 China Four-Year Review, 100% Duty

Key Points

• HTS 9903.91.08 applies a 100% additional duty on top of the normal column 1 rate for Chinese-origin articles covered by U.S. note 31(i) to Chapter 99, effective for entries on or after January 1, 2026.
• The code was created as part of the Section 301 four-year review escalation series under subchapter III of Chapter 99, alongside codes such as 9903.91.03 through 9903.91.07.
• Only one HTSUS subheading (4015.12.10) was ever listed under this code, and that product-scope rule ran from January 1, 2026 through February 1, 2026 only. It is no longer in force as of the facts date of October 14, 2026.
• Because zero product-scope rules are currently active under 9903.91.08, no goods are covered by this code today. Importers should confirm the current status in the HTSUS or with a licensed customs broker.
• Any entries of subheading 4015.12.10 made between January 1, 2026 and February 1, 2026 that claimed this code should be reviewed for duty accuracy, potential refund eligibility, or correction posture.

On this page

1. What HTS 9903.91.08 is and where it comes from
2. Rate structure: how the 100% additional duty works
3. Product scope: the one subheading and its closed window
4. Current status: what is covered today
5. How this code appears on a customs entry
6. Interaction with other Section 301 duties
7. What importers should do
8. Key references

HTS 9903.91.08 is a Chapter 99 overlay code that imposes an additional 100% duty on Chinese-origin goods listed in U.S. note 31(i) to subchapter III of Chapter 99, effective for entries on or after January 1, 2026. As of October 14, 2026, the only product-scope rule that was ever assigned to this code covered HTSUS subheading 4015.12.10 for a narrow window of January 1, 2026 through February 1, 2026. That window has closed, meaning no goods are currently covered under 9903.91.08.

The links in this article go to the primary documents: the Federal Register notices, White House proclamations, and the official Harmonized Tariff Schedule pages themselves. Read the source.

What HTS 9903.91.08 is and where it comes from

The 9903.91.xx series of tariff codes was created as part of the Section 301 four-year statutory review of tariffs on goods imported from China. This review process allowed the United States Trade Representative to increase, maintain, or reduce Section 301 rates following an extensive investigation and public comment period. The 9903.91.xx codes reflect rate escalations resulting from that review, separate from the original List 1 through List 4 rates carried under the 9903.88.xx series.

9903.91.08 sits within that escalation framework and carries the highest rate in the series: 100% added on top of the otherwise applicable column 1 general rate. For context on adjacent codes in the same series, see our articles on 9903.91.03 (100% duty), 9903.91.07 (50% duty), and 9903.91.06 (25% duty).

The official heading text in the HTSUS reads: "Effective with respect to entries on or after January 1, 2026, articles the product of China, as provided for in subdivision (i) of U.S. note 31 to this subchapter." Confirm the current heading text and any amendments at the official tariff schedule, hts.usitc.gov.

Rate structure: how the 100% additional duty works

The HTSUS general column rate for 9903.91.08 is: the duty provided in the applicable subheading + 100%.

This means the 100% is layered on top of, not in replacement of, the ordinary column 1 rate that applies to the underlying chapter 1 through 97 subheading. Here is how the math works in practice:

• Take the normal column 1 general rate for the chapter 1-97 subheading (for example, the base MFN rate for 4015.12.10).
• Add 100% of the customs value on top of that.
• The result is the total duty owed per unit of value.

At 100%, this is one of the steepest overlay rates in the entire Section 301 structure. Even if a base MFN rate is low or zero, the 100% surcharge alone is substantial.

Product scope: the one subheading and its closed window

U.S. note 31(i) to subchapter III of Chapter 99, as reflected in the HTSUS, defines which chapter 1-97 subheadings fall within the scope of 9903.91.08. As of October 14, 2026, the facts show that exactly one product-scope rule was ever assigned to this code:

• Subheading 4015.12.10, covered from January 1, 2026 through February 1, 2026.

Subheading 4015.12.10 covers a specific category of rubber gloves. That window lasted approximately one month before closing on February 1, 2026.

Check the current text of U.S. note 31 at hts.usitc.gov to confirm whether any additional subheadings have been added since the facts date of October 14, 2026.

Current status: what is covered today

As of October 14, 2026, zero product-scope rules are in force under 9903.91.08. The single rule that existed, for subheading 4015.12.10, expired on February 1, 2026. No goods are currently being assessed the 100% additional duty under this specific code.

If you import goods that were previously classified under 4015.12.10 and are now looking for the applicable Section 301 rate, confirm with a licensed customs broker or check the HTSUS directly at hts.usitc.gov to determine which code, if any, now governs those goods. See our 2026 tariff code overview for additional context on the current landscape.

How this code appears on a customs entry

Like all Chapter 99 overlay codes, 9903.91.08 does not replace the underlying chapter 1-97 classification. It rides alongside it on the entry summary. During the active window, a broker would have entered:

• Line 1: The chapter 1-97 subheading, for example 4015.12.10, with its normal column 1 rate.
• Line 2: 9903.91.08, with the additional 100% rate applied to the same customs value.

Both lines appear in ACE on the same entry. The system calculates the surcharge separately. CBP guidance on Section 301 entry reporting is available at cbp.gov. For a broader look at how to verify a broker's duty calculation on an entry, see How Do I Check Whether My Broker Calculated the Duty Correctly?

Interaction with other Section 301 duties

The 9903.91.xx series escalation codes are separate from the original 9903.88.xx List 1 through List 4 codes. Goods that were subject to a 9903.88.xx rate before January 1, 2026 may have had their Section 301 rate changed, replaced, or supplemented by a 9903.91.xx code as a result of the four-year review. It is important not to double-count: the applicable 9903.91.xx code for a given subheading governs the Section 301 rate for that product during its effective window; the original 9903.88.xx code does not stack on top.

Other codes in the 9903.91.xx series also carry 100%, 50%, or 25% additional duties on different product sets, with different effective windows. See, for example:

• 9903.91.03: 100% duty, different product scope
• 9903.91.02: 50% duty
• 9903.91.04: 25% duty
• 9903.91.05: 50% duty

If you have entries spanning multiple periods or multiple product lines, confirm which code was operative for each entry date and each subheading. Do not assume a single code applies across an entire calendar year.

What importers should do

• Audit entries dated January 1, 2026 through February 1, 2026 for subheading 4015.12.10 to confirm 9903.91.08 was applied correctly. If the 100% surcharge was missed or over-collected, determine the appropriate correction or refund posture with your broker.
• Confirm current coverage by checking U.S. note 31(i) in the live HTSUS at hts.usitc.gov before filing any new entries, since no rules are currently in force under this code as of October 14, 2026.
• Verify the correct Section 301 code for any ongoing imports of rubber gloves or related goods from China, as a different 9903.xx.xx code may now apply. Confirm with a licensed customs broker or CBP at cbp.gov.

Key references

• Harmonized Tariff Schedule of the United States (USITC): Official text of 9903.91.08 and U.S. note 31(i) to subchapter III of Chapter 99.
• U.S. Customs and Border Protection (CBP): Entry filing guidance, CSMS messages, and Section 301 implementation instructions.
• Federal Register: Notices and rules implementing Section 301 four-year review rate changes.
• White House: Presidential proclamations and executive orders related to Section 301 tariff actions on China.
• 19 U.S.C. Section 2411 (Cornell LII): Statutory authority for Section 301 trade actions.