9903.88.01 Explained: Section 301 China 25% Tariff Rate and Scope

Key Points

• HTS 9903.88.01 imposes an additional 25% duty on top of the normal column 1 rate for Chinese-origin goods covered by U.S. Note 20(a) and enumerated in U.S. Note 20(b) to Subchapter III of Chapter 99.
• The 25% rate is stated in the HTSUS general column as "the duty provided in the applicable subheading plus 25%," meaning the base rate still applies and 9903.88.01 is purely additive.
• Seventeen exception headings (9903.88.05 through 9903.88.69, as listed in the official heading text) can displace 9903.88.01 for specific product categories, countries of origin situations, or exclusions; importers must check whether any exception heading applies before defaulting to 9903.88.01.
• The code applies only to articles that are products of China and that appear in the subheadings enumerated in U.S. Note 20(b); goods not listed there are not covered regardless of their country of origin.
• As of October 9, 2026, this code and its 25% rate remain active; confirm current status in the live HTSUS or with your broker before filing.

On this page

1. What 9903.88.01 is and who needs to care
2. Product and country scope: U.S. Notes 20(a) and 20(b)
3. The 25% additional rate and how it stacks
4. Exception headings that can displace 9903.88.01
5. How 9903.88.01 appears on a customs entry
6. What importers should do
7. Key references

HTS 9903.88.01 is the Chapter 99 classification line that imposes an additional 25% Section 301 duty on Chinese-origin merchandise whose normal chapter 1-97 subheading appears in U.S. Note 20(b) to Subchapter III of Chapter 99. Every importer bringing goods from China needs to check whether their product's base HTS number is enumerated in that note, because if it is, and no exception heading applies, the 25% additional duty is mandatory. The links throughout this article go directly to the primary documents: the official Harmonized Tariff Schedule, CBP guidance pages, and federal government publications themselves. Read the source.

What 9903.88.01 is and who needs to care

Chapter 99 of the Harmonized Tariff Schedule is reserved for temporary legislation, including special tariff programs layered on top of the permanent tariff structure in chapters 1 through 97. The 9903.88.xx series covers additional duties imposed on Chinese-origin goods under the Section 301 trade action program. Code 9903.88.01 is the primary, general-rate line within that series.

The official HTSUS heading text for 9903.88.01 reads: "Except as provided in headings 9903.88.05, 9903.88.06, 9903.88.07, 9903.88.08, 9903.88.10, 9903.88.11, 9903.88.14, 9903.88.19, 9903.88.50, 9903.88.52, 9903.88.58, 9903.88.60, 9903.88.62, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(a) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(b)."

Any importer, customs broker, or trade compliance team handling merchandise made in China should treat this code as a first check on every entry line. Getting it wrong can mean underpaying duties, triggering CBP interest, or filing an incorrect entry that requires a post-summary correction or protest. See our article on correcting HTS classification after entry if you need to address a past filing.

Product and country scope: U.S. Notes 20(a) and 20(b)

Country of origin requirement

9903.88.01 applies exclusively to articles that are products of China. Country of origin is determined under CBP's substantial transformation rules (or, for textile and apparel, specific tariff shift rules). Origin determines whether this Chapter 99 code even comes into play; goods manufactured outside China from Chinese components may or may not qualify as Chinese-origin products depending on the transformation analysis. Confirm the origin determination with your broker if there is any doubt.

U.S. Note 20(a): program authority

U.S. Note 20(a) to Subchapter III of Chapter 99 establishes the legal framework for the Section 301 additional duties on Chinese-origin goods. The note defines the program's scope and the authority under which the duties were imposed. You can review the current note text directly in the official online HTSUS at hts.usitc.gov.

U.S. Note 20(b): the enumerated subheading list

U.S. Note 20(b) contains the actual list of chapter 1-97 subheadings whose products are subject to the 9903.88.01 duty when imported from China. If a product's base classification subheading does not appear in Note 20(b), 9903.88.01 does not apply, even if the goods are of Chinese origin. The note is extensive and has been amended multiple times; always check the current, in-force version at hts.usitc.gov rather than relying on a cached or printed schedule. For a broader orientation to the 2026 tariff schedule, see our 2026 tariff code overview.

The 25% additional rate and how it stacks

The stated rate

As of October 9, 2026, the HTSUS general column rate for 9903.88.01 is: the duty provided in the applicable subheading plus 25%. The base duty is whatever rate applies in the chapter 1-97 subheading for that product, including any column 1 general rate. The 25% is calculated on the customs value of the goods and added on top.

How stacking works in practice

When you file an entry for a Chinese-origin product covered by 9903.88.01, your entry will carry two HTS lines for that product:

• The chapter 1-97 classification line (for example, a line in chapters 84, 85, or 73), which generates the normal MFN duty.
• The 9903.88.01 line in Chapter 99, which generates the additional 25% Section 301 duty on the same customs value.

Both are reported on the same entry summary. CBP collects both amounts. There is no netting or offset between them. If other special duties also apply to the same goods (for example, antidumping or countervailing duties), those layer on further still. Online tariff calculators sometimes miss stacked Chapter 99 duties, which is a common source of miscalculated landed costs.

Exception headings that can displace 9903.88.01

The heading text for 9903.88.01 opens with a critical phrase: "Except as provided in headings 9903.88.05, 9903.88.06, 9903.88.07, 9903.88.08, 9903.88.10, 9903.88.11, 9903.88.14, 9903.88.19, 9903.88.50, 9903.88.52, 9903.88.58, 9903.88.60, 9903.88.62, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69."

These seventeen exception headings cover situations such as product-specific exclusions, different rate tiers, or other special treatment within the Section 301 program. When one of these exception headings applies, it takes precedence over 9903.88.01 for the goods it covers. The practical consequence is that importers cannot simply stop at 9903.88.01. The full 9903.88.xx series must be reviewed to determine whether an exception heading is more specific to the product being imported.

The scope and conditions of each exception heading are defined in the HTSUS and the associated U.S. notes. Check the current schedule at hts.usitc.gov for the precise coverage of each exception heading listed above. If the facts governing any exception heading are material to a pending entry, confirm the current text with your licensed customs broker before filing.

How 9903.88.01 appears on a customs entry

On CBP Form 7501 (the entry summary) and in ACE, 9903.88.01 is entered as a secondary classification line beneath the primary chapter 1-97 line for the same article. The sequence matters: the base classification must be reported first, followed by the Chapter 99 duty line. The 25% additional duty is computed on the same entered value used for the base duty calculation.

Brokers filing in ACE should be aware that the Chapter 99 line does not replace the chapter 1-97 line; both must appear. An entry that reports only 9903.88.01 without the underlying chapter 1-97 subheading is incomplete. Similarly, an entry that reports the chapter 1-97 line but omits 9903.88.01 when it applies will result in a duty underpayment. For entries processed through a Foreign Trade Zone, the timing and value basis for Section 301 duties has its own rules; see our article on FTZ weekly entry procedures for context.

If an entry was filed incorrectly and the window for a post-summary correction is still open, that is generally the fastest path to resolution. After liquidation, a protest is the primary avenue. Review the options in our article on correcting HTS classification after entry.

What importers should do

• Verify your base subheading against U.S. Note 20(b). Pull up the current HTSUS at hts.usitc.gov and confirm whether your chapter 1-97 subheading appears in Note 20(b) before every entry involving Chinese-origin goods.
• Check all seventeen exception headings. Review 9903.88.05 through 9903.88.69 to determine whether any exception heading covers your specific product. Skipping this step can result in both overclaiming and underclaiming duties.
• Build 25% into your landed-cost model. The additional duty is calculated on customs value and stacks on top of MFN duties, antidumping duties, and countervailing duties, if any. Confirm your duty bill reflects all applicable layers.
• Correct past entries promptly. If prior entries omitted 9903.88.01 when it applied, or claimed it when an exception heading should have applied instead, assess whether a post-summary correction, protest, or prior disclosure is appropriate given the liquidation status of those entries.

Key references

• Harmonized Tariff Schedule of the United States (hts.usitc.gov) - Official, continuously updated tariff schedule; source for 9903.88.01 rate text and U.S. Notes 20(a) and 20(b).
• U.S. Customs and Border Protection (cbp.gov) - CBP guidance, CSMS messages, and entry filing requirements for Section 301 duties.
• Federal Register (federalregister.gov) - Federal Register notices establishing and amending Section 301 China duties and product lists.
• White House (whitehouse.gov) - Presidential proclamations and executive orders related to Section 301 trade actions.
• 19 U.S.C. 2411 - Section 301 statutory authority (law.cornell.edu) - The underlying statute authorizing Section 301 trade actions.