Importers of HS 3402.50 (containing any aromatic or modified aromatic surface-active ) from Mexico actually paid 10% on the taxed portion of the value in 2026-06 — 0.03% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 4%. Over the window the rate on the taxed portion moved null% → 10%, with the largest single step +29pp in 2025-08. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 4% — importers actually paid 10%, so the trade-war overlay added 6 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "3402.50", origin: "Mexico") · see it at trimtabist.com/tariffs
HS 3402.50. The schedule base rate is 4%; importers from Mexico actually paid 10% on the dutiable value in 2026-06 — the trade-war overlay added 6 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved % (2023-07) → 10% (2026-06), largest single step +29pp in 2025-08.
Mexico's lower duty (0.03% vs 35.3%) lets it price up to 35.3% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, Mexico actually lands cheaper — $1.03/kg vs $2.29/kg (duty in, freight out).
5 Chapter-99 measures name Mexico; 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 Mexico · the whole tariff ledger · reproduce: tariff_story(hs: "3402.50", origin: "Mexico") via /connect. Not customs or legal advice.