8409.91—Suitable for use solely or principally with spark-ignition internal combustion piston engines (including rotary engines)
General duty rate
Free – 2.5%
Across 11 10-digit lines; pick a line below for the exact rate
Coverage on this page
Up one level: 8409 — Parts suitable for use solely or principally with the engines of heading 8407 or 8408: (heading)
Plain-English explanation
HTS 8409.91 is a 6-digit subheading of the U.S. Harmonized Tariff Schedule covering Suitable for use solely or principally with spark-ignition internal combustion piston engines (including rotary engines). It sits in Chapter 84: Nuclear reactors, boilers, machinery and mechanical appliances; parts thereof, Section XVI: Machinery and Mechanical Appliances; Electrical Equipment; Parts Thereof; Sound Recorders and Reproducers, Television Image and Sound Recorders and Reproducers, and Parts and Accessories of Such Articles and rolls up 11 10-digit statistical lines, with general duty rates ranging from Free to 2.5%. 27 Chapter 99 tariff modifications currently touch one or more lines under this subheading, and 3 AD/CVD orders flag at least one child line.
10-digit lines under 8409.91(11)
Pick a line to view full rate detail and compute landed duty
8409.91.10.40For vehicles of subheading 8701.21, 8701.22, 8701.23, 8701.24 or 8701.29, or heading 8702, 8703 or 8704Free8409.91.10.60For marine propulsion enginesFree8409.91.10.80OtherFree8409.91.30.00Aluminum cylinder heads2.5%8409.91.50.10Connecting rods2.5%8409.91.50.81Steel forgings2.5%8409.91.50.85Other2.5%8409.91.92.10Connecting rods2.5%8409.91.92.90Other2.5%8409.91.99.10Connecting rods2.5%8409.91.99.90Other2.5%Tariff modifications(27)
Chapter 99 overlays touching one or more lines under 8409.91
| Code | Authority | Rate |
|---|---|---|
| 9903.94.05 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.94.07 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.94.06 | section_232 | The duty provided in the applicable subheading |
| 9903.94.42 | section_232 | The duty provided in the applicable subheading |
| 9903.94.43 | section_232 | 15% |
| 9903.94.52 | section_232 | The duty provided in the applicable subheading |
| 9903.94.53 | section_232 | 15% |
| 9903.94.44 | section_232 | The duty provided in the applicable subheading |
| 9903.94.45 | section_232 | 15% |
| 9903.94.54 | section_232 | The duty provided in the applicable subheading |
| 9903.94.55 | section_232 | 15% |
| 9903.94.62 | section_232 | The duty provided in the applicable subheading |
| 9903.94.63 | section_232 | 15% |
| 9903.94.64 | section_232 | The duty provided in the applicable subheading |
| 9903.94.65 | section_232 | 15% |
| 9903.94.32 | section_232 | 10% |
| 9903.94.33 | section_232 | 10% |
| 9903.74.08 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.74.10 | section_232 | The duty provided in the applicable subheading |
| 9903.74.11 | section_232 | The duty provided in the applicable subheading |
| 9903.74.09 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.91 | section_232 | The duty provided in the applicable subheading + a duty of 50% upon the value of the steel content. |
| 9903.81.92 | section_232 | The duty provided in the applicable subheading. |
| 9903.81.98 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.80.03 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.86 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.84 | section_232 | The duty provided in the applicable subheading + 25% |
AD/CVD orders(3)
Antidumping or countervailing orders covering one or more lines under 8409.91
A-570-119ADChinaCertain Large Vertical Shaft Engines Between 225cc and 999cc, and Parts ThereofA-570-124ADChinaCertain Vertical Shaft Engines, between 99cc and up to 225cc, and parts thereofC-570-125CVDChinaCertain Vertical Shaft Engines a Displaced, between 99 Cubic Centimeters and up to 225cc, and parts thereofFrequently asked questions
What does HTS 8409.91 cover?
HTS 8409.91 is a 6-digit subheading of the U.S. Harmonized Tariff Schedule covering Suitable for use solely or principally with spark-ignition internal combustion piston engines (including rotary engines). It belongs to Chapter 84 and rolls up 11 10-digit statistical lines that brokers actually file at entry.
What is the duty rate for HTS 8409.91?
General (Column 1) duty rates for the 10-digit lines under HTS 8409.91 range from Free to 2.5%. The exact rate depends on the specific 10-digit statistical line — pick a line below to see its full rate detail.
How do I find the right 10-digit line under HTS 8409.91?
U.S. Customs requires entries to be filed at the 10-digit statistical level — the broader subheading HTS 8409.91 is not directly fileable. Match your product description to the most specific 10-digit line in the list on this page; if multiple lines could apply, the General Rules of Interpretation (GRIs) and chapter notes determine which one governs.
Are there AD/CVD orders affecting HTS 8409.91?
Yes — 3 AD/CVD orders flag at least one 10-digit line under HTS 8409.91. Whether a specific shipment falls in scope depends on the country of origin and the order's scope determination. See compliance.tandom.ai for full coverage detail.
Learn more
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