Importers of HS 8501.31 (exceeding 37.5 w but not exceeding 74.6 w) from Mexico actually paid 8.56% on the taxed portion of the value in 2026-06 — 1.39% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 2.8%. Over the window the rate on the taxed portion moved 3.36% → 8.56%, with the largest single step +21.9pp in 2025-03. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 2.8% — importers actually paid 8.56%, so the trade-war overlay added 5.8 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "8501.31", origin: "Mexico") · see it at trimtabist.com/tariffs
HS 8501.31. The schedule base rate is 2.8%; importers from Mexico actually paid 8.56% 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 3.36% (2023-07) → 8.56% (2026-06), largest single step +21.9pp in 2025-03.
Mexico's lower duty (1.39% vs 24.67%) lets it price up to 23% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $12.97/kg vs $124.1/kg (duty in, freight out).
7 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 · 18 CBP rulings cite this code · reproduce: tariff_story(hs: "8501.31", origin: "Mexico") via /connect. Not customs or legal advice.