How to use TariffOS

1. What TariffOS answers

Four questions, in the order they usually get asked:

• Which official U.S. tariff measures hit which of my products? Matched on HTS code and country of origin against a curated dataset where every measure links to its own Federal Register notice, proclamation or CBP guidance.
• What is that costing me? From your entered value and duties paid where you supply them — never from a rate we guessed.
• What changes next? Effective dates, expiries, comment deadlines and court rulings on the positions you actually hold.
• What should I ask my broker? The gaps in your own data, turned into specific questions with the reason each one matters.

2. Before you start: get the right file

Start with a CSV or TSV; there is no template. What you bring decides what you can be told, so the inputs are ranked. If you can get the first one, get the first one.

Subject: ACE entry summary extract request

Hi [broker],

Could you send me an extract of our entry summary (CBP 7501) data for the last
12 months, as CSV or Excel? Ideally with these columns:

  - entry number and entry date
  - HTS number as filed (10 digits)
  - country of origin
  - line description
  - entered value
  - duty paid (including any Section 301 / 232 amounts, broken out if you have them)

Our own filings only — nothing else needed. Thanks.

3. Step 1 — Run your first import

Go to /import and drop the file. There is no account, no template and no field mapping to fill in first.

Columns are identified by what is in them, not what they are called. A column of ten-digit numbers is read as an HTS code whether its header says “HTS”, “Code”, or nothing at all — files with no header row work too. The result names what it thinks the file is and what evidence it used.

4. Step 2 — Check how your columns were read

Press Check columns on the result bar. Each column shows the field it was mapped to, the evidence for that decision, and a sample value. Anything that was read from contents against its header is flagged read from contents.

Correct anything wrong with the dropdown, or set it to Not used. Every figure on the page recomputes immediately. This costs thirty seconds and is the single highest-value check in the whole flow — a mis-read entered-value or duty column changes the headline, while a mis-read cost changes downstream scenarios.

5. Step 3 — Read the headline number

The big number is not always the same number. Which one you get depends entirely on what your file could support, and the page tells you which one you are looking at.

Press Open the full report to move the parsed rows into the editable catalog workspace. That working copy is stored in this browser’s local storage, not uploaded to TariffOS, so it can survive a reload on this device. You can stay on the import screen instead if your next task is the brief or alert request below.

6. Step 4 — Clear the classification queue

Rows without an HTS code cannot be checked against product-specific measures — only country-wide ones. Rather than a list of hundreds, they are grouped by product similarity, so one decision classifies a whole group. Confirm with Apply to N.

Suggestions are at heading level and are a starting point, not a classification. Every group links out to CROSS ruling search and to the HTS schedule for exactly this reason: you are responsible for the final code. A confirmed suggestion stays marked as a suggestion throughout the report, and the brief lists it as a gap until a real code replaces it.

7. Step 5 — Think in positions, not SKUs

Fifty SKUs of the same shirt from the same country are one tariff position. TariffOS rolls your rows up into distinct HTS + origin combinations, and everything downstream — the brief, watchlist and any future position alert — works on those.

This is not a display choice. Alerting per SKU would bury the signal it exists to deliver: a single Section 301 change would fire fifty notifications for one decision. A catalog of 400 rows commonly collapses to a dozen positions, and a dozen positions is something a person can actually hold in their head.

8. Step 6 — Build the broker brief

Press Build a broker-ready brief. This is the artefact you forward — to a CFO, a procurement lead, or your customs broker — so it is written to be read by someone who has never seen TariffOS. Use Print / save as PDF on the brief itself to send it; the PDF contains the brief alone, without the app around it.

What it contains, in order:

1. The headline with its footing stated — duties paid if you supplied them, entered-value exposure when the file supports it, otherwise a product count.
2. What is affecting these positions — each measure in force, its status, the rate exactly as published, which of your positions it touches, its dates, and a link to the official source.
3. Excluded pending verification — measures that touch your positions but whose recorded status no longer matches their own dates. They are not counted in any figure, and they are listed anyway, because omitting them silently would understate your exposure.
4. Your positions — a table of HTS + origin, products, entered value, duties paid, and status.
5. What is stopping a firm answer — every data gap written as a consequence and a fix, not a label. “Only 6 digits, so a 301 list can match a product it does not cover” rather than “short HTS”.
6. Questions to send your customs broker — the point of the document, each with the reason it matters.

The gaps section is deliberately as prominent as the findings. A brief that hid its own uncertainty would be worse than no brief, because it would be acted on.

9. Step 7 — Save the watchlist and request alerts

At the bottom of the result, add an email to save your positions and join the position-alert early access list. Note where this sits: your result is already complete and on screen. The email never unlocks a number you have already earned.

10. With an account: catalog, analyst, weekly brief

Everything above works signed out. An account exists for the things that need to persist between visits.

Plans and current limits are on /pricing. Paid plans are in limited rollout and are activated by request — creating an account does not charge you, and hitting a limit stops the limited action rather than deleting anything.

11. Reference: the public measure library

No account, no import. Useful on its own, and the source record behind every measure match in your report.

• Latest changes— What moved recently, newest first.
• Deadlines— Effective dates, expiries and comment windows that are coming up.
• Countries— Every measure by country of origin.
• Search— Across measures, countries and HTS codes.
• Methodology— Where the data comes from, how status is verified, and what is deliberately not covered.
• /hs/<code>— everything touching an HTS chapter or heading, e.g. /hs/8708 for motor vehicle parts.
• /measures/<slug>— one measure in full: timeline, rates as published, legal authority, challenges, and every source.

12. Reference: the free calculators

Standalone tools for a single question. They do not need a file or an account.

• Impact scanner— One HTS code plus one origin — which measures match, right now.
• Import duty calculator— Landed cost from customs value, freight, insurance and a rate you supply.
• Consumer price impact— What a tariff rate does to a shelf price at a given pass-through.
• Policy tracker— Live Federal Register trade announcements.
• Savings simulator— Two duty rates compared over your annual volume.

The calculators take a rate from you. They are arithmetic tools; the measure library is where rates come from, and it states them as published.

13. How to read a measure page

Every measure carries two independent labels. Status is where it stands in its lifecycle; signal strength is how legally solid the evidence is. They answer different questions, and conflating them is how people act on a press remark as though it were implementation guidance.

Status

Signal strength, weakest first

From federal_register_notice upward, a compliance-relevant instrument exists. Below it, something has been said but nothing has been filed. Measures also carry a status verified date — the day a person last confirmed the status specifically. If a measure’s own dates contradict its recorded status, it is demoted at runtime and excluded from collecting counts and exposure figures rather than quietly counted.

14. Troubleshooting

Almost none of my rows got classified.

Your file probably has no HTS column. That is normal for a store or accounting export. Work the grouped queue on the import page — one confirmation classifies every row in a group — or ask your broker for an entry extract, which arrives already classified.

A column was read as the wrong field.

Open "Check columns" on the result. Columns are matched on their contents rather than their headers, so a column titled "Code" holding 10-digit numbers is read as an HTS code even if it meant something else. Change it in the dropdown and every figure recomputes.

My entered-value or duty total looks too low.

Open "Check columns" and confirm the entered-value and duties-paid fields. TariffOS sums only figures present in those fields; it does not fill missing customs values from unit costs, volumes or industry assumptions.

A measure I know about is not counted.

Look for the "Excluded pending verification" section on the brief. A measure whose recorded status no longer matches its own dates is listed but never counted, because this document gets acted on. Open the measure and check its source.

My HTS code matched a measure I do not think applies.

Check the digit count. Section 301 lists and 232 inclusions are drawn at 8 and 10 digits, so a 6-digit code can match a measure that does not cover your product. Use the full 10-digit code from your entry summary.

I closed the tab and lost my result.

The import screen itself is temporary. Re-drop the file, or press "Open the full report" before leaving; that keeps a working copy in this browser’s local storage. Saving an alert request keeps only the HTS + origin positions and your email, not the uploaded file.

15. What TariffOS will not do

Worth knowing up front, because each of these is a decision rather than a missing feature:

• —Infer a duty rate from a measure, or multiply one by your value to produce a figure.
• —Turn unit cost × volume into customs entered value. Exposure dollars require entered value or duties paid from your file.
• —Report a measure as collecting when its own dates contradict that status.
• —Put a dollar amount on refund exposure — those measures apply origin-wide, and an entry total does not break duties out by measure.
• —Show a sample or placeholder result in place of a real one. Where there is nothing to show, you get an empty state that says so.
• —Give you a classification. It suggests headings, links the rulings, and leaves the decision where the law puts it.
• —File anything with CBP. A refund or correction goes to a licensed broker or trade attorney.