Importers of HS 8302.42 (of iron or steel, of aluminum or of zinc) from Mexico actually paid 17.71% on the taxed portion of the value in 2026-06 — 12.03% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 3.9%. Over the window the rate on the taxed portion moved 3.89% → 17.71%, with the largest single step +24.6pp in 2025-03. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 3.9% — importers actually paid 17.71%, so the trade-war overlay added 13.8 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "8302.42", origin: "Mexico") · see it at trimtabist.com/tariffs
HS 8302.42. The schedule base rate is 3.9%; importers from Mexico actually paid 17.71% on the dutiable value in 2026-06 — the trade-war overlay added 13.8 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved 3.89% (2023-07) → 17.71% (2026-06), largest single step +24.6pp in 2025-03.
Mexico's lower duty (12.03% vs 30.39%) lets it price up to 16.4% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $1.68/kg vs $14.3/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 · 7 CBP rulings cite this code · reproduce: tariff_story(hs: "8302.42", origin: "Mexico") via /connect. Not customs or legal advice.