How to put a number on your tariff exposure
Your bank, your board and your buyers all ask the same question: what do tariffs cost us a year? How to work it out product by product, run what ifs, and keep the number current.
By the Othermile team
When tariffs change every few weeks, the question from a bank, a board or a buyer is always the same: how much does this cost us a year? That number is your tariff exposure, and you can work it out from a product list you probably already have.
The idea in one line
For each product you import or export across the border: yearly units, times unit value, times the duty, tariff and surtax rates that apply to it. Add them up and you have the yearly cost. Then do it again with the rules as they will be, or as they might be.
What you need for each product
| Field | Example | Why |
|---|---|---|
| SKU and description | FRM100, steel frame tubing | To recognise it later |
| Tariff code | 7306.61 | Sets the ordinary duty and which special measures apply |
| Country of origin | US | Tariffs and surtaxes target origins; CUSMA needs North American origin |
| Direction | Import into Canada | Each country charges its own |
| Yearly units | 4,000 | From last year's purchases or sales |
| Unit value | C$85 | The value customs uses, usually the price paid |
The tariff code is the field that most often goes wrong. If you are not sure of a code, start with the one on your last customs entry, or ask your broker.
Price each line with today's rules
For each product, add up what applies to it: the ordinary duty for its code and origin, any tariff or surtax on that origin and code, and the saving if it qualifies for CUSMA and you claim it. Multiply by yearly units and unit value.
Watch three things:
- Lists, not only rates. A surtax covers a list of tariff codes; a product is in or out by its code.
- Start and end dates. Many measures are announced with a date. Note what starts within the next few months.
- Exchange rates. US duties are charged in US dollars. Convert at a stated rate and date.
Run what ifs
The yearly number becomes useful when you can move it:
- What if the rate on our largest import goes up 15 points?
- What if we buy this part from Mexico instead of China and claim CUSMA?
- What if the surtax on US steel ends?
Each one is the same calculation with one input changed.
Keep it current
Rules change without notice. Run the numbers again when a measure covering your codes is announced, starts or ends, and keep each version so you can show how the cost moved.
Do it in minutes
Othermile's tariff exposure scanner does all of this from a spreadsheet: upload your products and see the yearly cost of duties, tariffs and surtaxes by product, the CUSMA savings, what ifs, and alerts when a rule that touches your products changes. Try the sample trailer maker, then upload your own list.
This guide explains public rules in plain language for general information. It is not customs, tax or legal advice; the exact tariff code, your paperwork and the carrier decide the final amount.
Keep reading
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