Guide page

How to estimate import duty without pretending the tariff line is the whole story.

A good estimate has four parts: the right customs value, a defensible rate, explicit low-value threshold behavior, and the non-duty costs that still land on the shipment.

Open the calculator Prep the HS-code brief

Base formula Estimated landed cost = product value + freight + insurance + brokerage + misc + FX buffer + duty + import tax

Duty is not always charged on the same base that tax is. That is why the calculator keeps those assumptions separate.

Step by step

Use this order when you estimate.

Step 1

Define the customs value basis

Start by checking whether your commercial reality is closer to FOB, CIF, or another basis. Many errors come from copying a rate onto the wrong declared base.

Step 2

Get the probable HS code range

If classification is still fuzzy, do not lock the duty rate yet. Build a quick broker brief with material, use, construction, and origin detail first.

Step 3

Model threshold behavior openly

Some markets waive duty but still collect VAT or shift the collection point. Do not hide that assumption inside one generic checkbox.

Step 4

Add the admin friction

Brokerage, disbursement, compliance checks, and FX buffer often decide whether a shipment still works, especially on smaller consignments.

Step 5

Stress-test the file

Run one cleaner scenario and one stressed scenario. If a freight slip or rate dispute breaks the economics, that changes the business decision now.

Step 6

Capture assumptions with the number

When someone sees the landed total later, they should also see the duty base, rate source, threshold mode, and whether brokerage was included.

Starter threshold map

How the built-in presets think about low-value relief

Preset	Threshold line used in the toolkit	Default relief treatment	Why it matters
United States	None by default	No automatic relief	The preset assumes broad de minimis treatment is not generally available, so the file is modeled without it.
United Kingdom	GBP 135	Waive duty only	Low-value customs-duty relief can exist while VAT still matters, often with collection-point complexity.
EU-like VAT mode	EUR 150	Waive duty only	The preset assumes VAT still applies, so the model separates duty relief from the tax layer.
Custom	User-defined	User-defined	Use this only when you have market-specific or broker-specific instructions the starter presets do not cover.

Where teams usually miss

Common import-duty estimation mistakes

Treating HS code as settled too early

If the rate changes meaningfully across two plausible headings, the real answer is classification work, not calculator confidence.

Using product value as a stand-in for landed reality

Freight, brokerage, and tax can move the economics more than expected, especially on low-ticket items or urgent shipments.

Pricing from the best case only

A business that prices from the cleanest scenario tends to relearn the same customs lesson every quarter.

Next step