9903.05.88: Civil Aircraft Section 301 Forced Labor Exemption

Key Points

• HTS 9903.05.88 is an exemption heading, not a duty: it removes or reduces the Section 301 forced labor duty that would otherwise apply to qualifying civil aircraft and related goods.
• The heading covers civil aircraft (all aircraft other than military aircraft), their engines, parts and components, other parts, components and subassemblies, and ground flight simulators and their parts and components.
• Eligibility is governed by subdivision (d) of U.S. Note 52 to Subchapter III of Chapter 99; goods must satisfy that note's criteria to claim this heading.
• The rate column for 9903.05.88 reads "The duty provided in the applicable subheading," meaning the importer pays the ordinary Chapter 1-97 duty rate but is relieved of any Section 301 forced labor surcharge.
• As of September 19, 2026, this heading appears in the Section 301 forced labor exemption block that begins at 9903.05.85; confirm current HTSUS text at hts.usitc.gov before filing.

On this page

1. What 9903.05.88 is and why it matters
2. Scope: which products qualify
3. How the exemption works on an entry
4. U.S. Note 52(d): the legal gateway
5. Interaction with other tariff provisions
6. What importers should do
7. Key references

HTS 9903.05.88 is a claim heading under the Section 301 forced labor framework. When an importer correctly invokes it on an entry, the Section 301 forced labor additional duty does not apply to eligible civil aircraft, engines, parts, components, subassemblies, and ground flight simulators. The ordinary Chapter 1-97 rate still applies; this heading provides relief from the forced labor surcharge only. Importers of qualifying civil aviation goods and their brokers need to understand the scope, the legal note that gates eligibility, and how to place the code on a CBP entry correctly.

The links in this article go to the primary documents: the official tariff schedule, CBP guidance pages, and government legal sources themselves. Read the source.

What 9903.05.88 is and why it matters

Chapter 99 of the Harmonized Tariff Schedule of the United States contains a series of special-purpose headings that operate alongside a product's ordinary Chapter 1-97 classification. Most headings in the 9903.05 block impose Section 301 forced labor duties on goods from specific countries. The headings from 9903.05.85 onward, however, work in the opposite direction: they are exemption or exception headings that carve certain products out of those surcharges.

9903.05.88 sits within that exemption block. Its function is to signal to CBP that the merchandise on a given entry line qualifies for relief from the Section 301 forced labor additional duty. Without this heading on the entry, an importer's goods could be assessed the forced labor surcharge that applies to the country of origin under a companion heading. With it, only the regular tariff rate is owed.

For context on how neighboring exemption headings operate, see our article on 9903.05.85 Section 301 Forced Labor Transit Exemption Explained.

Scope: which products qualify

The official HTSUS heading text for 9903.05.88, as of September 19, 2026, covers:

• Civil aircraft: all aircraft other than military aircraft
• Engines of civil aircraft
• Parts and components of civil aircraft and their engines
• Other parts, components, and subassemblies of civil aircraft
• Ground flight simulators and their parts and components

Military aircraft are explicitly excluded from this heading's scope. If your merchandise is a military aircraft or a part exclusively designed for military use, 9903.05.88 does not apply. For all other aircraft and related goods, scope is broad but is subject to the additional eligibility requirements in subdivision (d) of U.S. Note 52 to Subchapter III of Chapter 99 (discussed below). If you are uncertain whether a specific part or subassembly falls within the heading, confirm the classification against the current HTSUS at hts.usitc.gov or with your broker.

How the exemption works on an entry

Dual-line reporting

Chapter 99 exemption headings do not replace the underlying Chapter 1-97 classification. On a CBP entry, the broker reports both lines: the ordinary classification (for example, a heading in Chapter 88 for aircraft or Chapter 84 for engines) and 9903.05.88 as a secondary Chapter 99 line on the same entry. This dual-line structure tells CBP's Automated Commercial Environment (ACE) system that the merchandise is within scope of the forced labor duty program but is claiming exemption under 9903.05.88.

Rate on the 9903.05.88 line

The HTSUS general column rate for 9903.05.88 reads: "The duty provided in the applicable subheading." That means no separate or additional duty is imposed by this heading. The importer owes whatever rate the Chapter 1-97 subheading carries, and the Section 301 forced labor surcharge is not added. This is the practical benefit of claiming the heading.

Burden of proof

Claiming an exemption heading shifts attention to documentation. CBP may request evidence that the merchandise qualifies under U.S. Note 52(d). Importers should be prepared with commercial invoices, airworthiness certifications, bills of lading, and any other records that establish the civil (non-military) nature of the goods and their conformity with the note's requirements. For guidance on overcoming CBP scrutiny in forced labor contexts generally, see UFLPA Rebuttable Presumption: How to Overcome It at CBP.

U.S. Note 52(d): the legal gateway

The heading text explicitly ties eligibility to subdivision (d) of U.S. Note 52 to Subchapter III of Chapter 99. That note is the controlling legal authority for this exemption. It defines which civil aircraft goods qualify, what conditions apply, and potentially what documentation or certifications are required. The facts block for this article does not reproduce the full text of Note 52(d); confirm its exact current language in the official HTSUS at hts.usitc.gov before claiming this heading on a live entry.

This matters because the note, not the heading description alone, determines eligibility. A product may appear to fall within the broad heading text (civil aircraft parts, for instance) but still fail to qualify if Note 52(d)'s specific conditions are not met. Your classification and compliance review should start with the note, not end with the heading.

Interaction with other tariff provisions

Section 301 country-specific duty headings

The Section 301 forced labor program assigns additional duties to goods from specific countries through headings such as 9903.05.79 (Turkiye), 9903.05.80 (UAE), 9903.05.81 (United Kingdom), 9903.05.82 (Uruguay), 9903.05.83 (Venezuela), and 9903.05.84 (Vietnam), among others. When a shipment of civil aircraft goods originates in a country subject to one of those headings, 9903.05.88 is the mechanism that removes the surcharge, provided the Note 52(d) criteria are satisfied. The exemption heading and the duty heading are paired; you cannot claim 9903.05.88 without first determining which, if any, country-specific duty heading would otherwise apply.

Other Chapter 99 provisions

Civil aircraft parts may also be subject to other Chapter 99 provisions, such as Section 232 steel and aluminum tariffs or other Section 301 tariffs tied to different trade actions. 9903.05.88 addresses only the forced labor duty. Importers must independently evaluate whether other Chapter 99 headings apply to their goods and whether separate exemptions are available for those programs. Confirm the full duty stack using the current HTSUS or a duty calculator such as the one at CustomsGenius Duty Calculator.

Most-favored-nation and preferential rates

The Chapter 1-97 rate that remains payable after claiming 9903.05.88 may itself be reduced by a free trade agreement, the Civil Aircraft Agreement, or another preferential program, depending on the country of origin and the specific subheading. 9903.05.88 does not affect or alter those preferential rates; they apply (or do not apply) on the Chapter 1-97 line as they ordinarily would.

What importers should do

• Verify eligibility under U.S. Note 52(d) before filing. Pull the current text of Note 52(d) from hts.usitc.gov and confirm that your specific goods, country of origin, and supply-chain circumstances satisfy every condition the note imposes.
• Report both lines on the entry. Work with your broker to enter the Chapter 1-97 classification and 9903.05.88 as a paired secondary line in ACE; omitting either line creates classification or liquidation risk. For a broader view of 2026 Chapter 99 codes and filing mechanics, see 2026 Tariff Code Overview.
• Assemble and retain supporting documentation. Keep commercial invoices, airworthiness records, and supply-chain records that establish the non-military, civil-aviation nature of the goods and compliance with Note 52(d); CBP can request these at any time.
• Monitor HTSUS amendments. The Section 301 forced labor exemption block is an active area of trade policy. Check hts.usitc.gov and federalregister.gov regularly for revisions to Note 52 or changes to companion headings that could affect your duty exposure.

Key references

• Harmonized Tariff Schedule of the United States (USITC): Official source for 9903.05.88 heading text, U.S. Note 52(d), and all applicable rates.
• U.S. Customs and Border Protection (CBP): Entry filing guidance, CSMS messages, and ACE requirements for Chapter 99 exemption headings.
• Federal Register: Notices and rulemakings related to Section 301 forced labor duty actions and amendments.
• White House Proclamations and Executive Orders: Presidential actions establishing and modifying the Section 301 forced labor framework.
• Office of the United States Trade Representative (USTR): Section 301 program administration and country-specific determinations.
• 9903.05.85 Section 301 Forced Labor Transit Exemption Explained: Companion exemption heading in the same block.
• UFLPA Rebuttable Presumption: How to Overcome It at CBP: CBP documentation standards in forced labor reviews.