Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 2903.51.10.00 is the U.S. Harmonized Tariff Schedule classification for 2,3,3,3-Tetrafluoropropene (HFO-1234yf),1,3,3,3-tetrafluoropropene (HFO-1234ze) and (Z)-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz). It's a 10-digit statistical line in Chapter 29: Organic chemicals, Section VI: Products of the Chemical or Allied Industries, used by U.S. Customs and Border Protection to determine the duty rate at entry. 6 Chapter 99 tariff modifications currently stack on top of the base rate.
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Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.80.03 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.84 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.86 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.91 | 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% |
HTS 2903.51.10.00 is the U.S. Harmonized Tariff Schedule classification for 2,3,3,3-Tetrafluoropropene (HFO-1234yf),1,3,3,3-tetrafluoropropene (HFO-1234ze) and (Z)-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz). It belongs to Chapter 29 of the HTSUS.
The general (Column 1) duty rate for HTS 2903.51.10.00 is 3.7%. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 2903.51.10.00 from countries party to a trade program (such as USMCA, KORUS, GSP, or the African Growth and Opportunity Act) may qualify for the special rate: Free(A, AU, BH,CL, CO, D, E, IL, JO, K, KR, MA, OM, P, PA, PE, S, SG). Eligibility depends on rules of origin and certification.
The Column 2 rate for HTS 2903.51.10.00 is 25%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
Yes — HTS 2903.51.10.00 is covered by section_232 provision 9903.80.03 (The duty provided in the applicable subheading + 25%). 5 additional overlays also touch this code. Open the code page for the full overlay stack with effective dates and country scopes.
No active AD/CVD orders currently flag HTS 2903.51.10.00 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
Free Trade Agreement and special-program eligibility
Tandom guides relevant to this code
How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
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