9903.94.43 Explained: Japan Auto Parts 232 Additional 15% Duty

Key Points

• HTS 9903.94.43 imposes a 15 percent additional duty on parts of passenger vehicles and light trucks that are products of Japan, covering parts whose column 1 (MFN) rate is less than 15 percent ad valorem.
• Coverage under this code began on September 16, 2025 and has no announced end date as of October 6, 2026.
• The 15 percent rate under 9903.94.43 is additional to the underlying MFN rate, not a replacement for it, so the total duty owed is the MFN rate plus 15 percent.
• Eligibility is defined by two U.S. Note 33 subdivisions: subdivision (l) identifies the qualifying parts, and subdivision (m) sets the less-than-15-percent MFN threshold that triggers this code rather than a different Chapter 99 heading.
• 134 product-country rules are currently in force under this code, spanning rubber, glass, spring, lock, engine, pump, compressor, and other auto parts subheadings, all limited to Japanese-origin goods.

On this page

1. What 9903.94.43 covers and how the program works
2. Affected products and HTS subheadings in scope
3. The 15 percent rate and how it stacks with other duties
4. Effective date and applicability window
5. How 9903.94.43 appears on a customs entry
6. Interaction with other Section 232 auto provisions
7. What importers should do
8. Key references

HTS 9903.94.43 is a Section 232 Chapter 99 overlay code that adds 15 percent to the duty on qualifying parts of passenger vehicles and light trucks originating in Japan. It applies specifically where the underlying column 1 MFN rate on the part is less than 15 percent ad valorem. The code took effect on September 16, 2025, and remains in force with no announced end date as of October 6, 2026. Importers and brokers must claim this code alongside the regular chapters 1-97 classification on every covered entry.

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

What 9903.94.43 covers and how the program works

The Section 232 automobile and parts tariff program was established under the authority of Section 232 of the Trade Expansion Act. It subjects imports of passenger vehicles, light trucks, and their parts to additional duties when national-security findings support that action. For deal countries, including Japan, the program works through negotiated arrangements that set specific rates and product lists, documented in U.S. Note 33 to Subchapter III of Chapter 99 of the Harmonized Tariff Schedule of the United States (HTSUS).

The official heading text for 9903.94.43 reads: Parts of passenger vehicles and light trucks that are products of Japan as provided for in subdivision (l) of U.S. note 33 to this subchapter, with an ad valorem (or ad valorem equivalent) rate of duty under column 1 less than 15 percent as provided for in subdivision (m) of U.S. note 33 to this subchapter.

Two subdivisions of U.S. Note 33 govern this code:

• Subdivision (l) enumerates which parts subheadings qualify. Only parts explicitly listed there are in scope.
• Subdivision (m) sets a threshold: if the column 1 MFN rate on the underlying subheading is less than 15 percent, the importer uses 9903.94.43. If the MFN rate is 15 percent or higher, a different Chapter 99 heading applies. Confirm the correct heading for any borderline subheading in the current HTSUS or with your broker.

For context on a closely related heading that applies to Japanese auto parts with a higher MFN base rate, see our article on 9903.94.41: Japan Autos 232 Combined 15% Rate. For the exemption heading under the same program, see 9903.94.06: Section 232 Autos Exemption Heading.

Affected products and HTS subheadings in scope

As of October 6, 2026, 134 product-country rules are in force under 9903.94.43, all limited to goods of Japan. One rule has ended and is not covered today. The in-force rules all share a start date of September 16, 2025 and have no announced end date.

The covered subheadings span a wide range of vehicle parts categories, including:

• Rubber hoses and tubes: 4009120020, 4009220020, 4009320020, 4009420020
• Tires (new and retreaded): 40111010, 40111050, 40112010, 40121940, 40121980, 40122060
• Inner tubes and rubber parts: 4013100010, 4013100020, 4016996010
• Automotive glass: 70072151, 70091000
• Springs: 732010, 73202010
• Locks and hinges: 83012000, 83021030, 830230
• Spark-ignition engines (under 1,000 cc, and larger displacement brackets): 84073100, 840732, 840733, 840734
• Compression-ignition (diesel) engines: 84082020
• Engine parts: 8409911040, 8409991040
• Fuel pumps and pump parts: 84133010, 84133090, 84139110, 8413919010
• Air compressors and fans: 8414308030, 84145930, 8414596540, 84148005
• Air conditioning units: 84152000
• Oil filters and air filters: 84212300, 84213200
• Jacks and hoists: 84254900, 84269100

The facts block shows the first 40 of 135 total rules (134 in force). Verify full coverage in subdivision (l) of U.S. Note 33 in the current HTSUS.

The 15 percent rate and how it stacks with other duties

The duty imposed by 9903.94.43 is 15 percent additional. It is added on top of the underlying MFN (column 1) rate. It is not a replacement for MFN, and it is not a combined rate that swallows MFN.

For example, if a covered Japanese auto part carries a 2.5 percent MFN rate, the total duty rate on that entry line is 2.5 percent plus 15 percent, for a combined effective rate of 17.5 percent. The 15 percent figure is the additional amount only.

This stacking structure is exactly as the facts for this code describe it. It differs from some other deal-country auto arrangements where the Chapter 99 rate is a combined inclusive rate. Under 9903.94.43, the MFN rate is not extinguished; it continues to apply alongside the 15 percent add-on. Confirm how any other Section 232 or additional tariff provisions interact with your specific goods by checking the current HTSUS notes or with your customs broker.

To estimate total landed duty costs across your Japan-origin parts portfolio, the CustomsGenius duty calculator accounts for stacked Chapter 99 overlays.

Effective date and applicability window

All 134 in-force product-country rules under 9903.94.43 became effective on September 16, 2025. There is no announced end date as of October 6, 2026. The program continues until a proclamation or executive order modifies or terminates it.

Because the entry date determines which rate applies, goods entered or withdrawn from warehouse for consumption on or after September 16, 2025 are subject to the 15 percent additional duty. For goods entered before that date, the code did not yet exist. See our article on why the entry date changes the duty on a U.S. import for how CBP determines the controlling date.

How 9903.94.43 appears on a customs entry

Chapter 99 codes do not replace a good's chapters 1-97 classification. On a CBP entry, an importer must report both the regular subheading (for example, 8409.91.1040) and 9903.94.43 on a separate line. The 15 percent additional duty is then assessed against the dutiable value on that line.

Key filing considerations:

• The country of origin must be Japan. Third-country origin goods, even if they incorporate Japanese parts, are not covered by this code.
• The underlying column 1 MFN rate on the chapters 1-97 subheading must be less than 15 percent. If the MFN rate is 15 percent or higher, a different Chapter 99 code applies, not 9903.94.43.
• The parts subheading must appear in subdivision (l) of U.S. Note 33. Filing 9903.94.43 against a subheading not listed there is a classification error.
• Customs value and the dutiable basis for the additional duty follow normal CBP valuation rules. For no-charge or warranty replacement shipments, see Customs Value for No-Charge Shipments: Samples and Warranty Goods.

Interaction with other Section 232 auto provisions

The Section 232 autos and parts program includes multiple Chapter 99 headings. The heading that applies to any given shipment depends on the country of origin, the parts subheading, and the MFN rate level. For Japan-origin auto parts:

• 9903.94.43 covers parts listed in subdivision (l) of U.S. Note 33 with an MFN rate less than 15 percent.
• A separate heading (such as 9903.94.41) applies to Japan-origin parts with different rate characteristics. Verify which heading applies to your specific subheading in the current HTSUS.
• The exemption and certification pathway under 9903.94.06 may be relevant for certain parties. See 9903.94.06: Section 232 Autos Exemption Heading for details.

If your goods are also subject to other Section 301 or additional tariff programs, check whether those programs separately apply. The facts block for 9903.94.43 addresses only the 15 percent Section 232 additional duty. Confirm any interaction with other overlay duties in the current HTSUS or with your broker.

What importers should do

• Verify classification: Confirm that your parts subheading appears in subdivision (l) of U.S. Note 33 in the current HTSUS, that your goods are of Japanese origin, and that the column 1 MFN rate is less than 15 percent before applying 9903.94.43.
• Calculate total duty correctly: Add the 15 percent additional duty to (not in place of) the MFN rate. Use the CustomsGenius duty calculator to model stacked rates across your parts list.
• Audit open entries: Review entries filed on or after September 16, 2025 to confirm that 9903.94.43 was claimed where required and that the 15 percent additional duty was assessed on each covered line.
• Monitor for changes: The program has no announced end date, but proclamations can alter scope, rates, or country coverage. Subscribe to Federal Register notices and CBP guidance to stay current.

Key references

• Harmonized Tariff Schedule of the United States (HTSUS), hts.usitc.gov -- Official schedule including Chapter 99, U.S. Note 33, and subdivision (l) and (m) product lists.
• U.S. Customs and Border Protection (CBP), cbp.gov -- Entry filing guidance, CSMS messages, and liquidation information for Section 232 auto parts duties.
• Federal Register, federalregister.gov -- Notices and proclamations establishing and modifying the Section 232 autos and parts program.
• White House proclamations, whitehouse.gov -- Executive actions establishing Section 232 auto tariff authority and deal-country arrangements.
• 19 U.S.C. 1862 (Section 232, Trade Expansion Act), law.cornell.edu -- Statutory authority for national-security tariff actions.
• 9903.94.41 Explained: Japan Autos 232 Combined 15% Rate -- Related Chapter 99 heading for Japan-origin auto parts under the same program.
• 9903.94.06 Explained: Section 232 Autos Exemption Heading -- Exemption and certification pathway under the Section 232 autos program.