How to Stress-Test Your Pricing When Tariffs Change

A tariff announcement can come with a start date only weeks away. Your costs move almost immediately. Your prices, your retail partners' price sheets, and your customers' expectations do not.

The brands that handle this well aren't better at predicting tariffs. They already know what a cost shock does to each product's margin, because they ran the numbers before the news broke. Here's how to stress-test your pricing the same way, in four steps, using a model you can rebuild any time the rules change.

What does it mean to stress-test your pricing?

To stress-test your pricing is to re-run your unit economics under a deliberate cost shock, so you can see how much margin each product loses and where it stops being worth selling at the current price. You aren't forecasting what will happen. You're finding out what you'd do if it did.

The output is small and useful: for each product, your landed cost under a few scenarios, the margin that results, and the price you'd need to hold your target. With that in hand, a tariff announcement becomes a lookup instead of a scramble.

Why do tariff changes hit your margin before they reach your prices?

Tariff changes hit your margin first because duty is charged when your goods are entered, and the market adjusts to higher costs more slowly. Under the general rule in US customs regulations, the rate of duty that applies is the rate in effect at the time of entry. Inventory you've already ordered, and even goods already on the water, can be exposed to a rate you didn't plan for. Check with your broker on how timing rules apply to a specific change.

The pass-through research points the same way. Economists at the New York Fed found that import prices rose almost one for one with tariffs in the first month (opens in new tab), with foreign exporters absorbing very little, while the full effect on consumer prices took about a year to build. That's economy-wide data on consumer goods, not your product, but it describes the squeeze: your costs jump in weeks, and prices across the market adjust over months.

Step 1: Build a baseline landed cost for each SKU

Start with what each product costs you today, delivered. The formula is the one in Izba's landed cost calculator: Landed Cost = Product Cost + Freight + Duty + Fees, all per unit.

Get the duty rate from your product's HTS code and country of origin. You can look up the code in the Harmonized Tariff Schedule (opens in new tab) or confirm it with your broker. If you haven't built a baseline before, our posts on FOB vs. landed cost and the hidden costs that blow up a landed cost estimate (opens in new tab) cover which costs belong in the fee line.

Do this for every SKU, then rank them by how much of your revenue and margin they carry. Sourcify's tariff guidance makes the reason clear: a 15% tariff on a top-selling SKU hits very differently than the same tariff on a niche product. (opens in new tab) Your best sellers get stress-tested first.

Step 2: Pick your shock scenarios

Choose three or four scenarios, and define each as a change to one input. Duty rate is the usual one, but it isn't the only one. A simple set looks like this:

• Duty rate up 10 points
• Duty rate up 25 points
• Duty rate up 50 points
• A second variable of your choice, such as freight up 20% or a supplier requote

The point isn't to guess the right number. It's to span a range wide enough that you find the level where a product stops working. If you can't name the scenario in advance, the 10, 25, and 50-point steps give you a useful spread for most products.

Step 3: Re-run landed cost and check your margin

Re-run the landed cost for each product under each scenario, then compare margin and the price you'd need to hold it. Here's one product as an example. The numbers are illustrative.

Say a product has a $12.00 FOB price, $0.80 freight per unit, $0.40 in fees, a 10% duty rate, and sells for $36.00. Baseline landed cost is $14.40, for a 60% landed margin. Landed margin here is selling price minus landed cost, divided by selling price. It leaves out fulfillment, marketing, and overhead.

The price to hold your margin is landed cost divided by one minus your target margin: $14.40 / 0.40 = $36.00 at baseline. Holding 60% under the +25 point scenario takes a 20.8% price increase, from $36.00 to $43.50. If your floor is 50%, this product survives a 25-point shock and doesn't survive a 50-point one.

The calculator gives you the landed cost per unit for each scenario. Change the duty rate, note the result, and repeat. The margin math is one more line in your spreadsheet.

Step 4: Decide your response before you need it

For each product, write down what you'd do at each scenario, while nothing is on fire. The usual levers are a price increase, a supplier requote, a different country of origin, a change in order timing or quantity, or absorbing the hit on products where margin allows it.

Two second-order costs belong in the same exercise. Higher product value means more cash tied up in inventory, and storage and insurance costs that scale with value. Returns get more expensive too, because every returned unit carries the higher landed cost. Sourcify cites Corso's figure of 10% to 35% return rates in fashion, textiles, and home goods, so a product with heavy returns takes a bigger hit than its landed margin suggests.

Then set a trigger for each product, such as "if landed margin drops below 50%, raise the price," so the decision is already made when the news arrives.

Common questions about stress-testing your pricing

How do I calculate the price I need to keep my margin? Divide the new landed cost by one minus your target margin. A $17.40 landed cost with a 60% target margin needs a price of $17.40 / 0.40 = $43.50.

Will my supplier absorb part of a tariff increase? Plan as if they won't. The New York Fed research found foreign exporters absorbed very little of the tariff increases it studied, though your supplier may differ. It's still worth asking for a requote, since freight and other terms may have room.

Does a tariff change apply to goods that have already shipped? Under the general rule, the rate in effect at the time of entry applies. Specific changes often carry their own effective dates and transition rules, so confirm the details with your customs broker before assuming goods in transit are exempt.

Run your own stress test

Pick your five best-selling products and run each one through Izba's landed cost calculator at today's duty rate, then again at 10, 25, and 50 points higher. Compare the margins, and you'll know where your pricing breaks before the next announcement does it for you.