Importers of HS 3917.40 (fittings) from Canada actually paid 14.05% on the taxed portion of the value in 2026-06 — 0.18% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 5.3%. Over the window the rate on the taxed portion moved 5.3% → 14.05%, with the largest single step +18.8pp in 2025-03. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 5.3% — importers actually paid 14.05%, so the trade-war overlay added 8.8 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "3917.40", origin: "Canada") · see it at trimtabist.com/tariffs
HS 3917.40. The schedule base rate is 5.3%; importers from Canada actually paid 14.05% on the dutiable value in 2026-06 — the trade-war overlay added 8.8 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved 5.3% (2023-07) → 14.05% (2026-06), largest single step +18.8pp in 2025-03.
Canada's lower duty (0.18% vs 39.01%) lets it price up to 38.8% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $6.59/kg vs $79.94/kg (duty in, freight out).
7 Chapter-99 measures name Canada; 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 Canada · the whole tariff ledger · 2 CBP rulings cite this code · reproduce: tariff_story(hs: "3917.40", origin: "Canada") via /connect. Not customs or legal advice.