Importers of HS 8538.90 (other) from Korea, South actually paid 10.73% on the taxed portion of the value in 2026-06 — 10.38% across everything shipped, taxed or not. Measured from official duty receipts, not the rulebook: the statutory MFN base rate on this code is 3.5%. Over the window the rate on the taxed portion moved 3.5% → 10.73%, with the largest single step +5.7pp in 2025-04. Measured from official US duty receipts · as-of 2026-06 · confidence: measured, not modelled. The HTS base rate is 3.5% — importers actually paid 10.73%, so the trade-war overlay added 7.2 pts, measured at the border (not a summed rulebook estimate). Reproduce exactly: tariff_story(hs: "8538.90", origin: "Korea, South") · see it at trimtabist.com/tariffs
HS 8538.90. The schedule base rate is 3.5%; importers from South Korea actually paid 10.73% on the dutiable value in 2026-06 — the trade-war overlay added 7.2 points, measured at the border. Measured, not modelled.
Over the window the collected rate moved 3.5% (2023-07) → 10.73% (2026-06), largest single step +5.7pp in 2025-04.
Korea, South's lower duty (10.38% vs 37.91%) lets it price up to 24.9% above China at the factory and still match on duty-inclusive customs cost. But on the LATEST measured prices, China actually lands cheaper — $7.92/kg vs $23.8/kg (duty in, freight out).
2 Chapter-99 measures name Korea, South; 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 South Korea · the whole tariff ledger · 25 CBP rulings cite this code · reproduce: tariff_story(hs: "8538.90", origin: "South Korea") via /connect. Not customs or legal advice.