Importers of HS 3824.99 (fatty substances of animal or vegetable origin and mixtures ) from Japan actually paid 10.41% on the taxed portion of the value in 2026-06 — 10.4% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 4.6%. Over the window the rate on the taxed portion moved 5.01% → 10.41%, with the largest single step +3.8pp in 2025-09. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 4.6% — importers actually paid 10.41%, so the trade-war overlay added 5.8 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "3824.99", origin: "Japan") · see it at trimtabist.com/tariffs
HS 3824.99. The schedule base rate is 4.6%; importers from Japan actually paid 10.41% on the dutiable value in 2026-06 — the trade-war overlay added 5.8 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved 5.01% (2023-07) → 10.41% (2026-06), largest single step +3.8pp in 2025-09.
Japan's lower duty (10.4% vs 35.34%) lets it price up to 22.6% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $5.86/kg vs $19.86/kg (duty in, freight out).
12 Chapter-99 measures name Japan; 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.
All goods from Japan · the whole tariff ledger · 38 CBP rulings cite this code · reproduce: tariff_story(hs: "3824.99", origin: "Japan") via /connect. Not customs or legal advice.