9903.88.15 Explained: Section 301 China List 4, 7.5% Duty Rate

Key Points

• HTS 9903.88.15 adds a 7.5% Section 301 duty on top of the normal column 1 rate for covered articles from China, as reflected in the HTSUS as of October 11, 2026.
• Coverage is defined by two U.S. notes: U.S. Note 20(r) identifies the program conditions, and U.S. Note 20(s) lists the specific Chapter 1-97 subheadings that fall under this code.
• Goods that qualify for one of the exception headings, specifically 9903.88.39, 9903.88.42, 9903.88.44, 9903.88.47, 9903.88.49, 9903.88.51, 9903.88.53, 9903.88.55, 9903.88.57, 9903.88.65, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, are carved out and do not use 9903.88.15.
• The Chapter 99 code rides alongside the regular Chapter 1-97 classification line on every entry; both must appear for a valid filing.
• Confirm current applicability, any active exclusions, and whether your specific subheading is still enumerated in U.S. Note 20(s) in the current HTSUS or with your broker before filing.

On this page

1. What 9903.88.15 is and why it matters
2. Goods and countries in scope
3. The 7.5% rate and how it stacks
4. Exception headings that override 9903.88.15
5. How this code appears on a customs entry
6. What importers should do
7. Key references

HTS 9903.88.15 is a Section 301 Chapter 99 overlay code that imposes an additional 7.5% duty on articles that are the product of China and are classified in the Chapter 1-97 subheadings enumerated in U.S. Note 20(s) to Subchapter III of Chapter 99, subject to the conditions in U.S. Note 20(r). It applies on top of whatever column 1 general rate already applies to the underlying subheading. Any importer sourcing from China whose goods appear in the Note 20(s) subheading list must declare this code on every entry, unless a specific exception heading applies instead.

The links in this article go to the primary documents: the official tariff schedule, U.S. Customs and Border Protection guidance pages, and the Federal Register. Read the source.

What 9903.88.15 is and why it matters

Section 301 of the Trade Act of 1974 authorizes the United States Trade Representative to impose additional duties on goods from countries found to engage in unfair trade practices. The duties collected under the 9903.88 series represent the result of USTR action against China across multiple product lists. HTS 9903.88.15 is one of several codes in that series; each code targets a defined subset of Chinese goods at a specific additional rate.

This particular code covers what is commonly described as part of the List 4 tranche of Section 301 China tariffs, carrying a 7.5% additional rate. It is distinct from the 25% codes found elsewhere in the 9903.88 series. For context on how other List 4 codes work, see the related articles on 9903.88.04 and 9903.88.03. For the broader landscape of Section 301 List 3 codes, see the article on 9903.88.09.

All facts below are as of October 11, 2026. Check the official HTSUS at hts.usitc.gov and CBP.gov for any changes after that date.

Goods and countries in scope

Country of origin

Only articles that are the product of China are subject to 9903.88.15. Country of origin is determined under CBP's standard substantial-transformation rules, not the country of shipment or the country of the seller. Goods transshipped through a third country remain Chinese-origin if China is where the last substantial transformation occurred.

Product scope: U.S. Notes 20(r) and 20(s)

The official heading text states that 9903.88.15 covers articles "as provided for in U.S. note 20(r) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(s)." In practice this means two things must be true simultaneously:

• U.S. Note 20(r) sets the program-level conditions, such as the origin and legal framework under which these additional duties operate.
• U.S. Note 20(s) contains the specific list of Chapter 1-97 subheadings whose products are covered. If your product's eight- or ten-digit HTS subheading does not appear in Note 20(s), 9903.88.15 does not apply to it under this code.

Review both notes in the current HTSUS before filing. The subheading list in Note 20(s) can be amended, and the published schedule at hts.usitc.gov is authoritative. A summary of 2026 tariff code changes is also available at our 2026 tariff code overview.

The 7.5% rate and how it stacks

The HTSUS general column rate for 9903.88.15 is stated as: "The duty provided in the applicable subheading + 7.5%." That means the total duty an importer pays is the sum of two components:

• The column 1 general rate of the underlying Chapter 1-97 subheading (which could be ad valorem, specific, or compound).
• An additional 7.5% ad valorem imposed by 9903.88.15.

The 7.5% is calculated on the customs value of the merchandise, consistent with how ad valorem duties generally work under CBP valuation rules. It does not reduce or offset the normal column 1 rate; it is purely additive.

Interaction with other Section 301 codes

The 9903.88 series contains numerous codes, each covering a different product universe or rate tier. A single shipment cannot be subject to two 9903.88 overlay codes simultaneously. The exception headings listed directly in the 9903.88.15 heading text (see next section) are the mechanism by which overlapping or superseding treatment is assigned. If your product falls under one of those exception codes, that code governs instead of 9903.88.15.

Interaction with Section 232 and other Chapter 99 duties

Section 232 duties (for steel, aluminum, and derivative products) operate under a separate Chapter 99 subchapter and a separate legal authority. Where both a Section 232 code and 9903.88.15 apply to the same article, both additional duties stack on top of the column 1 rate. Confirm stacking treatment with your broker and review any relevant CBP CSMS messages for entry instructions. For reference on how Section 232 derivative codes work, see the article on 9903.85.07.

Exception headings that override 9903.88.15

The heading text opens with the phrase "Except as provided in headings..." followed by a list of thirteen specific codes. If an article qualifies for any of those headings, it does not use 9903.88.15. The carve-out headings named in the official text are:

• 9903.88.39
• 9903.88.42
• 9903.88.44
• 9903.88.47
• 9903.88.49
• 9903.88.51
• 9903.88.53
• 9903.88.55
• 9903.88.57
• 9903.88.65
• 9903.88.66
• 9903.88.67
• 9903.88.68
• 9903.88.69

These exception codes typically reflect exclusions granted by USTR or later-enacted modifications that redirect certain products to a different rate or treatment. Check the HTSUS to determine what each exception heading covers and whether your goods qualify. If your product is covered by one of these exception codes, you must use that code on the entry, not 9903.88.15.

How this code appears on a customs entry

Chapter 99 codes are not standalone entries. Every import entry that triggers 9903.88.15 must show two HTS lines:

1. The regular Chapter 1-97 classification line (the substantive classification that describes what the product is).
2. The Chapter 99 overlay line, 9903.88.15, which carries the additional 7.5% duty.

Both lines must appear in ACE (the Automated Commercial Environment). The duty calculation engine applies the column 1 rate to the first line and the additional 7.5% to the second. Omitting the Chapter 99 line is a classification error that can trigger a CBP CF-28 request for information or a CF-29 notice of action. For practical guidance on entry filing timelines, see the article on customs entry filing deadlines.

If you believe you overpaid because 9903.88.15 was applied in error, the standard remedy is a protest filed with CBP within the statutory period. If a protest is denied, the path to further review runs through the Court of International Trade. See the related article on protest denials and the CIT process for procedural context.

What importers should do

• Verify your subheading in U.S. Note 20(s). Pull the current HTSUS from hts.usitc.gov and confirm your Chapter 1-97 subheading appears in the Note 20(s) enumeration before assuming 9903.88.15 applies.
• Check each shipment against the thirteen exception headings. If any of the listed exception codes cover your product, use that code instead of 9903.88.15 and document your analysis in your entry records.
• Ensure both the Chapter 1-97 line and 9903.88.15 appear on every affected entry. Work with your broker to confirm ACE transmits both lines with the correct duty basis and that your 7.5% additional duty is calculated on the correct customs value.
• Monitor USTR and Federal Register notices for list modifications. The Section 301 China tariff lists are subject to ongoing four-year statutory reviews and USTR actions that can change rates, add subheadings, or expand exclusions. Set up targeted tariff change alerts for the subheadings you import.

Key references

• Harmonized Tariff Schedule of the United States (hts.usitc.gov) -- The authoritative source for HTS 9903.88.15, U.S. Notes 20(r) and 20(s), and the current subheading enumeration.
• U.S. Customs and Border Protection (cbp.gov) -- CBP guidance, CSMS messages, and entry processing instructions for Section 301 duties.
• Federal Register (federalregister.gov) -- USTR notices establishing and modifying the Section 301 China tariff lists, including List 4 actions.
• White House (whitehouse.gov) -- Presidential proclamations and executive orders related to Section 301 trade actions.
• 19 U.S.C. Section 2411 -- Trade Act of 1974, Section 301 (law.cornell.edu) -- The statutory authority underlying Section 301 China tariffs.
• 9903.88.04 Explained: Section 301 China List 4, 25% Duty Rate -- Related List 4 code at a higher rate tier.
• 9903.88.03 Explained: Section 301 China List 4, 25% Duty Rate -- Related List 4 code at a higher rate tier.
• Protest Denied CIT: The 180-Day Road to Court of International Trade -- What to do if a Section 301 duty protest is denied by CBP.