8409.91.99—Suitable for use solely or principally with spark-ignition internal combustion piston engines (including rotary engines), otherGeneral duty rate
2.5%
Across 2 10-digit lines
Coverage on this page
HTS 8409.91.99 is an 8-digit tariff item of the U.S. Harmonized Tariff Schedule covering Suitable for use solely or principally with spark-ignition internal combustion piston engines (including rotary engines), other. 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 2 10-digit statistical lines, all with a general duty rate of 2.5%. 12 Chapter 99 flags link to one or more child lines (6 active, 6 expired), and 3 potentially relevant AD/CVD order flags link to at least one child line.
Pick a line to view its exact rate and estimate duties and customs fees
Provisions linked to one or more lines under 8409.91.99; applicability depends on origin, product facts, claims, and entry date
| Code | Authority | Rate |
|---|---|---|
| 9903.81.91 | section_232Expired | The duty provided in the applicable subheading + a duty of 50% upon the value of the steel content. |
| 9903.81.92 | section_232Expired | The duty provided in the applicable subheading. |
| 9903.81.98 | section_232Expired | The duty provided in the applicable subheading + 25% |
| 9903.88.01 | section_301Active | The duty provided in the applicable subheading plus 25% |
| 9903.74.08 | section_232Active | The duty provided in the applicable subheading + 25% |
| 9903.80.03 | section_232Expired | The duty provided in the applicable subheading + 25% |
| 9903.74.10 | section_232Active | The duty provided in the applicable subheading |
| 9903.81.86 | section_232Expired | The duty provided in the applicable subheading + 25% |
| 9903.74.11 | section_232Active | The duty provided in the applicable subheading |
| 9903.81.84 | section_232Expired | The duty provided in the applicable subheading + 25% |
| 9903.88.15 | section_301Active | The duty provided in the applicable subheading + 7.5% |
| 9903.74.09 | section_232Active | The duty provided in the applicable subheading + 25% |
HTS-linked orders for one or more lines under 8409.91.99; written scope controls whether a product is covered
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 thereofHTS 8409.91.99 is an 8-digit tariff item of the U.S. Harmonized Tariff Schedule covering Suitable for use solely or principally with spark-ignition internal combustion piston engines (including rotary engines), other. It belongs to Chapter 84 and rolls up 2 10-digit statistical lines that brokers actually file at entry.
Every 10-digit line under HTS 8409.91.99 carries a general (Column 1) duty rate of 2.5%. Chapter 99 flags and potentially relevant AD/CVD order flags are shown at the per-line level; applicability depends on the shipment facts, written scope, and entry date.
Tandom links section_232 provision 9903.81.91 to HTS 8409.91.99. Its published rate notation is The duty provided in the applicable subheading + a duty of 50% upon the value of the steel content., and its status on 2026-09-26 is expired. 11 additional Chapter 99 flags also link to this code. A flag is not a shipment-level determination; check origin, product facts, claims, and entry date.
U.S. Customs requires entries to be filed at the 10-digit statistical level — the broader tariff item HTS 8409.91.99 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.
Tandom links 3 potentially relevant AD/CVD order flags to at least one 10-digit line under HTS 8409.91.99. An HTS link is a screening aid; whether a shipment is covered depends on the order's written product scope and country of origin. Use the linked lookup to review the case materials.
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