How to calculate import duty and landed cost, step by step

The formula

Every calculation needs three inputs: the product's classification, its country of origin and its customs value. Most rates are a percentage of value, but some lines charge per unit or both: one footwear line, for example, is 90 cents a pair plus 37.5%^[1].

• Duty = customs value × (the general percentage rate for the HTS line + any additional duties that apply to the country of origin), plus quantity × any per-unit rate on the line
• Landed cost = the price you pay the seller + freight and insurance + duty + entry fees + customs broker, bond and delivery charges
• Landed cost per unit = landed cost ÷ units in the shipment

The rest of this guide fills in each input for goods entering the United States. The rates below are the ones in force when the page was checked, except where a line says it applies from a later date; each one links to its source and the date it was checked.

How to calculate import duty

1. Classify the product. Find its code in the Harmonized Tariff Schedule (HTS). The code depends on what the product is made of and how, which is why a precise spec matters: for apparel, knit versus woven and the fiber content change the line. Ask your customs broker to confirm the code before you place the order, not after the goods land.
2. Establish the country of origin. For customs purposes it is the country of manufacture, production, or growth^[2] of the goods, not the country they shipped from. Work done in a second country changes the origin only if it substantially transforms the product.
3. Find the customs value. It is normally the price paid for the goods, exclusive of the cost of transportation, insurance and related services for the international shipment^[3]. On an FOB quote, the FOB price is the usual starting point. On a CIF quote, take the ocean freight and insurance out first, which is only possible if the seller lists them separately.
4. Look up the general rate. The HTS lists a general rate for each line and, in a special column, lower rates for goods that qualify under a trade program. Cotton knit T-shirts are a useful example: the general rate is 16.5%^[4], and T-shirts that originate under the USMCA enter free of duty^[4].
5. Add the additional duties for the country of origin. These sit in the HTS chapter for temporary and additional duties and are charged on top of the general rate. Two apply to the example below: Section 301 duties on goods of China, which add 7.5%^[5] on cotton knit T-shirts, and a newer Section 301 action, taken over trading partners' failure to ban imports made with forced labor, that covers goods of each economy across the board, apart from listed exemptions, entered from July 24, 2026^[6]: 12.5%^[7] for China, 12.5%^[8] for Vietnam, 10%^[9] for India and 10%^[10] for Mexico. The Mexico duty does not apply to goods of Mexico entered duty free under the USMCA^[11].
6. Add the entry fees. The merchandise processing fee is 0.3464%^[12] of the value on a formal entry, with a minimum of $34.58 and a maximum of $670.86 per entry from October 1, 2026^[13], and it does not apply to goods originating under the USMCA^[12]. Ocean cargo also pays the harbor maintenance fee of 0.125%^[14] of its value. Goods that cross from Mexico by truck do not pay it, because it applies to cargo on a commercial vessel.
7. Add the costs that are not taxes. Ocean or truck freight, cargo insurance, the customs broker's fee, the customs bond, port and terminal charges and the trucking to your warehouse. Then divide the total by the number of units.

If you are reading an older calculator or blog post, check its date. Many were built around the tariffs imposed under the International Emergency Economic Powers Act, which CBP now lists as no longer in effect^[15]. If you find an additional duty heading that is not in the example below, check it against CBP's list of actions no longer in effect, and ask your broker, before you add it.

The same order landed from four countries

The same order is priced at the same FOB value in each country so that only duty, fees and freight differ. In practice the factory prices differ too, which is why you compare countries on landed cost, not unit price.

Order: 2,000 cotton knit T-shirts, FOB value $3.00 each, $6,000 in total. For the Mexico columns, "FOB value" means the value at export; a truck shipment would normally be quoted on a different Incoterm.

Line	China	Vietnam	India	Mexico, USMCA-originating	Mexico, not originating
Goods (FOB value)	$6,000	$6,000	$6,000	$6,000	$6,000
General duty at 16.5%[4]	$990	$990	$990	$0 (USMCA rate is free)	$990
Section 301, China list duty at 7.5%[5]	$450	none	none	none	none
Section 301, forced-labor import ban action (economy-wide)	$750 at 12.5%[7]	$750 at 12.5%[8]	$600 at 10%[9]	$0 (exempt)	$600 at 10%[10]
Merchandise processing fee at 0.3464%[12], with a minimum of $34.58 and a maximum of $670.86 per entry from October 1, 2026[13], so the minimum applies	$34.58	$34.58	$34.58	$0 (exempt)	$34.58
Harbor maintenance fee at 0.125%[14]	$7.50	$7.50	$7.50	$0 (truck)	$0 (truck)
Freight and insurance to the warehouse	$900	$950	$1,050	$700	$700
Customs broker, bond and port charges	$450	$450	$450	$450	$450
Landed cost	$9,582.08	$9,182.08	$9,132.08	$7,150.00	$8,774.58
Landed cost per unit	$4.79	$4.59	$4.57	$3.58	$4.39

Illustrative figures, not a quote. Real prices depend on the spec, quantity and factory.

Three things the table shows. First, duty layers stack: on this line, goods of China carry the general rate and two Section 301 duties. Second, the Mexico result depends almost entirely on whether the goods originate under the USMCA, so ask your broker to confirm that they qualify before you count on the free rate. Third, on a small order the processing fee minimum, not the percentage, sets the fee.

FOB, EXW and DDP: putting quotes on one basis

Factories quote on different Incoterms, and a lower number is not a lower cost until the quotes cover the same costs.

To compare, convert every quote to landed cost per unit at your warehouse. For EXW and FOB quotes, run the steps above. For a DDP quote, ask the seller which HTS code, customs value and rates it used for the duty inside its price, because the duty inside the price is only as right as those three inputs.

The quotes we send state their shipping terms, so you can see which of the costs above are already in our price and which are yours to add.

Where landed cost estimates go wrong

• An old rate. The additional duties have changed several times in the past two years. Re-check the rate against the current HTS before each order, not once per product.
• The wrong code. A misclassified product can carry a different rate and different additional duties, so have the broker confirm the code from your spec.
• The wrong origin. A product finished in one country from parts made in another keeps the parts' origin unless the work substantially transforms it.
• Freight inside the value. Duty worked out on a CIF price without taking the freight and insurance out overstates the duty.
• Small shipments. Fixed costs such as the fee minimum, the broker and the bond weigh far more per unit on a small first order than on a reorder, so check your first order and your reorder separately.