Importers of HS 8421.23 (oil or fuel filters for internal combustion engines) from Vietnam actually paid 27.15% on the taxed portion of the value in 2026-06 — 27.15% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 2.5%. Over the window the rate on the taxed portion moved 2.5% → 27.15%, with the largest single step +12.2pp in 2025-06. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 2.5% — importers actually paid 27.15%, so the trade-war overlay added 24.6 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "8421.23", origin: "Vietnam") · see it at trimtabist.com/tariffs
HS 8421.23. The schedule base rate is 2.5%; importers from Vietnam actually paid 27.15% on the dutiable value in 2026-06 — the trade-war overlay added 24.6 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved 2.5% (2023-07) → 27.15% (2026-06), largest single step +12.2pp in 2025-06.
Vietnam's lower duty (27.15% vs 48.85%) lets it price up to 17.1% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, Vietnam actually lands cheaper — $4.5/kg vs $7.74/kg (duty in, freight out).
All goods from Vietnam · the whole tariff ledger · 1 CBP ruling cite this code · reproduce: tariff_story(hs: "8421.23", origin: "Vietnam") via /connect. Not customs or legal advice.