How to Calculate Import Duty and Tariffs on Your Shipment

Your total is the base HTS duty rate, plus any trade-action tariffs that apply to your country of origin, plus federal user fees — all calculated on the customs value of the goods. Four steps: find the code, set the value, stack the rates, add the fees. This page shows you the method and where to look each rate up; it does not publish rates, for reasons explained below.

This Page Does Not Publish Rates

Duty rates change, and the rate that applies depends on your product's classification and its country of origin. Publishing a rate table here would mislead someone who reads it six months from now. So this page teaches you the method and points you at the official sources instead.

One warning that matters more in 2026 than usual. US tariff policy changed three times in the first eight months of this year, and further changes are being litigated. The rate that applies to your goods is generally the one in force on the day of entry, not the day you placed the order. Confirm with your broker before every shipment, not every quarter.

Step 1: Find Your HTS Code

Every product entering the US is classified under a 10-digit Harmonized Tariff Schedule code. That code determines your base duty rate and which trade actions apply to you. Nothing else does.

Look yours up at hts.usitc.gov. Search by plain description first — "cotton tote bag", "LED desk lamp" — then read the chapter notes around your result to confirm you are in the right heading.

Three things that go wrong here:

• Your supplier gave you a code. Suppliers guess, and they are not liable if the guess is wrong. You are, as importer of record. Treat their code as a starting point, not an answer.
• Material composition changes the code. A bag that is 60% cotton and one that is 60% polyester sit under different headings with different rates. Get the actual composition in writing.
• Function changes the code. A lamp with a built-in USB charging port may classify differently from a plain lamp. If your product does two things, check whether both matter.

While you are in the HTS database, check whether your heading carries a Chapter 99 cross-reference. That is where the trade-action tariffs live, and it is the fastest way to find out whether Section 301 hits your specific code.

If the classification is genuinely ambiguous and the order is large, a licensed customs broker will classify it for a modest fee. For a product you will import repeatedly, you can also apply to CBP for a binding ruling — slow, but it removes the uncertainty permanently.

Step 2: Determine the Customs Value

Duty is charged on a value, and getting the base wrong makes every number downstream wrong.

The US generally assesses duty on transaction value — the price actually paid for the goods themselves. International freight and insurance are typically not part of that base. This differs from many other countries, which use the CIF value.

The CIF case is one of the most common ways importers quietly overpay. It is worth checking on every entry.

One useful detail: MPF is calculated on the same goods value, excluding duty, freight, and insurance. So the tariff stack on top does not increase your MPF, however high those rates climb.

Step 3: Stack the Rates

This is the step that catches importers who last shipped a few years ago. You are no longer applying one rate. You are stacking several, and they all calculate off the same customs value.

The HTS gives your base rate in one of three forms:

• Ad valorem — a percentage of customs value. Most common.
• Specific — a fixed amount per unit or per kilogram, ignoring value entirely.
• Compound — both.

Then add the trade-action layers that apply to your origin. Depending on your product and where it was made, that can mean one layer or three. They add together on the same customs value — they do not compound on each other. Your HTS listing's Chapter 99 cross-references are where you find which ones apply to you.

Step 4: Add the Federal Fees

Two federal user fees ride along with duty on most commercial entries. Unlike duty rates, these do not depend on your product or origin — but the dollar limits are adjusted annually each October, so check the current figures at cbp.gov before you rely on them.

The Merchandise Processing Fee (MPF) is a small percentage of goods value, with a floor and a ceiling per entry. The floor matters more than importers expect: on a small shipment the minimum charge can exceed the percentage-based amount several times over. That is a real argument for consolidating small orders into fewer entries. It is one of several charges covered in our rundown of hidden import costs.

The Harbor Maintenance Fee (HMF) is a smaller percentage of goods value with no cap, and it applies to ocean shipments only. Air freight skips it entirely, which slightly narrows the cost gap between the two modes on high-value cargo.

Worked Example

500 LED desk lamps, $8.40 each FOB, shipped by ocean. Customs value $4,200.

The percentages below are arithmetic placeholders, not current rates. Replace every one of them with the figure you looked up for your own code and origin. The point of the example is the shape of the calculation, not the numbers.

Read that last line with the caveat attached. At these placeholder rates, lamps costing $8.40 pick up $3.48 each before a single dollar of freight — a 41% increase. Your own rates may be higher or lower, but the lesson holds: on many imports duty is the second-largest line in landed cost, not a rounding error. Anyone still treating it as a few percent is budgeting from a world that no longer exists.

Notice the MPF line too. Because it carries a per-entry minimum, a small shipment often pays the floor rather than the percentage. That is a real argument for consolidating orders.

Drop your own figures into our landed cost calculator alongside freight and handling to get the per-unit number your pricing should actually be built on.

Planning Around Rates That Keep Moving

Anyone importing in 2026 has watched the numbers change repeatedly. Two habits help.

Re-check before every shipment, not every quarter. The rate that applies is generally the one in force at entry. A container that left origin under one regime can arrive under another.

Model a second scenario at a higher rate. When you calculate margin on a new product, run a version with an extra 10–15 percentage points of duty. If the deal only works at today's rate, it is a fragile deal.

One more thing worth knowing: when tariffs are struck down in court, duties already paid can become refundable, and that has happened more than once in the last two years. Keep your entry summaries. Importers who could not produce documentation missed refund windows they were entitled to.

Frequently Asked Questions

Do I pay duty on shipping costs?

In the US, generally no. Duty is assessed on the transaction value of the goods, with international freight and insurance excluded. If your supplier's invoice bundles goods and freight into one number, ask them to split it — otherwise you may be declaring, and paying duty on, more value than you owe.

Do trade-action tariffs stack on top of the base duty rate?

Yes. They are additional duties layered on the base rate, and they add together rather than compounding — all calculated on the same customs value. A single product can carry several layers at once, which is why looking up only the base rate badly understates what you will owe.

What happens when a tariff is struck down in court?

Duties already paid can become refundable, and that has happened more than once recently. Refund claims run on deadlines and require documentation, so keep every entry summary. Importers who could not produce paperwork have missed windows they were entitled to. Your broker will know the current claim procedures.

What happens if I use the wrong HTS code?

If you underpaid, you owe the difference plus potential penalties, and repeated errors can trigger review of past entries. If you overpaid, recovery is possible but only within a limited window. The importer of record carries the responsibility, not the supplier or the broker.

Why is my Merchandise Processing Fee higher than the percentage suggests?

Because of the per-entry minimum. If the percentage calculation comes to less than the floor, you pay the floor. Small shipments hit this constantly, which is a real argument for consolidating orders into fewer, larger entries.

Does DDP mean I do not have to think about duty?

Not really. The duty is still being paid, just bundled into a price you cannot see, and you have no visibility into how the goods were declared. If the declaration is later questioned, that can become your problem. Our comparison of DDP vs FOB vs EXW covers where the risk actually sits.

Last updated: September 10, 2026.