How a US duty rate is actually built, on one line
Take a synthetic hoodie made in China, entering the US under 6110.30.30. Read the tariff schedule literally today and you arrive at 92%. The rate actually collected is 52%. Neither number is a typo, and the 40 points between them are the reason a duty figure is worth showing your working for.
What is charged
| Heading | What it is | Rate |
|---|---|---|
| 6110.30.30 | The product line itself, general column | 32% |
| 9903.05.31 | Per-country action on products of China | +12.5% |
| 9903.88.15 | Section 301 list action | +7.5% |
| Effective rate | 52% |
The first line is the only one most people look at, and on its own it is wrong by 20 points. The other two live in chapter 99, filed under the trade programme rather than next to the product, which is why a merchant reading their own tariff line in good faith does not find them.
What is printed but not charged
These 4 headings still appear in the published schedule, still carry a rate, and would be picked up by anything reading the text at face value. None of them is being collected.
| Heading | Why it is excluded | Rate |
|---|---|---|
| 9903.01.20 | IEEPA duties, struck down 20 February 2026Learning Resources, Inc. v. Trump, consolidated at the Supreme Court; followed by an executive action ending the tariffs and a CBP notice ending collection | +10% |
| 9903.01.24 | Same IEEPA block, same evidence | +10% |
| 9903.01.25 | Same IEEPA block, same evidence | +10% |
| 9903.03.01 | Section 122 surcharge, expired 24 July 2026A balance-of-payments surcharge may not run beyond 150 days without an Act of Congress, and none was passed. The proclamation and CBP's own guidance both name the end date | +10% |
| Still in the text, no longer collected | 40% |
Why this is the hard part
A duty layer does not disappear from the schedule when it stops being collected. A court strikes it down, or a statutory window expires, and the printed text carries on saying what it said before, sometimes for months. Anything that reads the schedule literally will keep adding those points.
The opposite failure is worse. An action can be legally in force before its headings appear in the published schedule, which is where the Canadian goods change on 19 August currently sits: the 5 headings for it are not in the schedule as I write this. Read the text literally that morning and you get a rate that is 50 points too low, which is the direction that costs a seller money quietly, because they price against it and absorb the difference.
So a rate that can be trusted needs 3 things beyond arithmetic. Every layer named, so the number can be checked. Evidence attached to every exclusion, so a layer is never dropped on a hunch. And an admission when the schedule and the law disagree, rather than a confident number papering over it.
How this one was checked
Every figure above was read from the live US schedule on 7 August 2026, HTS 2026 Revision 15. The exclusions each carry documented evidence: a court ruling, a Federal Register action, or a CBP notice, stored against the exclusion itself rather than applied by judgement. The effective rate is computed twice by 2 independent routes through the schedule and both have to agree, and this line is currently marked as needing review because they do not fully agree on one provision, which is stated on the rate rather than hidden.
You can check the working yourself. Each heading above resolves at hts.usitc.gov, and the same 52% appears with its layers itemised in the free rate table.
Doing this for a catalogue
One line took the work above. A catalogue has hundreds, each with its own origin, and the schedule changed 3 times in the last 6 months. That is the job Duty Diligence does: it reads the cost, HS code and country of origin already held in a Shopify store, shows the effective duty and the landed margin for every variant with this same working behind each number, and flags the ones that moved. The snapshot is free and needs no card.
Rates read from the USITC Harmonized Tariff Schedule, 2026 Revision 15, on 7 August 2026. Exclusion evidence: Learning Resources, Inc. v. Trump, No. 24-1287 (US, 20 February 2026) and the subsequent executive action and CBP guidance ending IEEPA collection; 19 U.S.C. 2132(a) and CBP guidance for the Section 122 surcharge window. Rates change, so the arithmetic above is true on the date shown rather than permanently. Informational, not customs, legal or financial advice.