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What China actually pays on 2,3,3,3-tetrafluoropropene (hfo-1234yf),1,3,3,3-tetrafluorop
Importers of HS 2903.51 (2,3,3,3-tetrafluoropropene (hfo-1234yf),1,3,3,3-tetrafluorop) from China actually paid 3.7% on the taxed portion of the value in 2026-06 — 3.7% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 3.7%. Over the window the rate on the taxed portion moved 3.7% → 3.7%, with the largest single step +33.7pp in 2025-07. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 3.7% — importers actually paid 3.7%, so the trade-war overlay added 0 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "2903.51", origin: "China") · see it at trimtabist.com/tariffs
HS 2903.51. The schedule base rate is
3.7%; importers from China actually paid 3.7% on the
dutiable value in 2026-06 — the trade-war overlay added 0 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved 3.7% (2023-07) → 3.7% (2026-06), largest single step +33.7pp in 2025-07.
The trade-war measures that name China or this sector
15 Chapter-99 measures name China; scope mapping is partial (several annexes are PDFs) — absence never means exemption. They do not sum, and some are product-specific — the collected rate above is the composed truth.
Notice of Modification: China's Acts, Policies and Practices Related to Technology Transfer, Intellectual Prop measure 9903.91.03 · Federal Register citation+100%
Notice of Modification: China's Acts, Policies and Practices Related to Technology Transfer, Intellectual Prop measure 9903.91.08 · Federal Register citation+100%
Notice of Modification and Proposed Modification of Section 301 Action: China's Targeting of the Maritime, Log measure 9903.91.14 · Federal Register citation+100%
Notice of Modification: China's Acts, Policies and Practices Related to Technology Transfer, Intellectual Prop measure 9903.91.02 · Federal Register citation+50%
Notice of Modification: China's Acts, Policies and Practices Related to Technology Transfer, Intellectual Prop measure 9903.91.05 · Federal Register citation+50%
Notice of Modification: China's Acts, Policies and Practices Related to Technology Transfer, Intellectual Prop measure 9903.91.07 · Federal Register citation+50%
9903.01.64 measure 9903.01.64+35%
Notice of Implementation of Additional Duties on Products of the People's Republic of China Pursuant to the… measure 9903.01.63 · Federal Register citation+34%
In print: “What China actually pays on 2,3,3,3-tetrafluoropropene (hfo-1234yf),1,3,3,3-tetrafluorop (HS 2903.51)” —
Trimtab US Trade Ledger (TT-010 Duty receipts), US Census imports-for-consumption records — trimtabist.com/tariff/290351/china