Every product imported into the United States is declared under a code of the Harmonized Tariff Schedule of the United States, the HTS. The code decides the duty rate and which additional duties can apply, so it is the first thing to get right: an estimate is only as good as the code it starts from.
What is an HTS code?
The HTS is the US customs tariff. The US International Trade Commission (USITC) publishes it, in editions revised many times a year. It sorts every product into sections, chapters and headings, down to the lines that carry the duty rates. An HTS code has ten digits, read from left to right like an address:
- 61
- The chapter: articles of apparel and clothing accessories, knitted or crocheted.
- 6109
- The heading: T-shirts, singlets, tank tops and similar garments, knitted or crocheted.
- 6109.10
- The subheading: of cotton. These first six digits are those of the Harmonized System, the nomenclature of the World Customs Organization that most countries share.
- 6109.10.00
- The US subheading: the eight-digit line that carries the US duty rates.
- 6109.10.00.12
- The statistical suffix: two more digits that sort the goods for US trade statistics, here other T-shirts for men. They have no rate of their own: the rates of their eight-digit line apply.
A US customs entry declares all ten digits.
Where to find your code
- On the supplier's commercial invoice. Many exporters print a code for each item. It is often the code of their own country's tariff, which shares the first six digits with the US code but not the last ones: check it in the US tariff.
- On a previous entry. If you have imported the same product before, the entry summary your broker filed (CBP Form 7501) shows the ten-digit code it declared.
- From your customs broker. Brokers classify goods for importers every day and can tell you which code they would declare, and why.
Whatever the source, keep the facts at hand: what the product is, what it is made of and what it is used for. Classification depends on them, not on its name in a catalog.
Search the tariff by product name
In TariffTrust's calculator, type a few words in the HTS code field, such as "cotton t-shirt": it suggests the lines of the tariff that match, each with its code. The HTS explorer searches the same way, by code or by words in any order, and opens the tariff section by section down to each line, with its duty rates and its place in the tariff. The calculator takes eight or ten digits; give all ten when you have them.
A search matches words, not meanings: try the material, the function and the usual names of the product, then read the lines it finds as below.
Read the whole description path
A line of the tariff is the last step of a path, and its own words often make sense only under the levels above it. Two lines of heading 6109, 6109.10.00.12 and 6109.10.00.18, both read "Men's". Only their paths tell them apart: both are under "Of cotton" and "Men's or boys'", but the first is under "Other T-shirts" and the second under "Tank tops and other singlets". The number in parentheses after their words in the tariff is a textile category for statistics, not a duty.
So read every level, from the chapter down, before you choose a line: the HTS explorer shows each line with its full path. Read the notes of the section and of the chapter too: they include or exclude goods, and can send a product that seems to belong under one heading to another. Lines that look alike can carry different rates, because of the material, the use, or even whom a garment is made for.
Have it confirmed
The importer of record is responsible for the code declared on the entry, and a wrong code can mean the wrong duty, delays or penalties. Two ways to be sure:
- A licensed customs broker. Brokers are licensed by US Customs and Border Protection (CBP): ask yours to confirm the code before the goods ship.
- A binding ruling from CBP. You can ask CBP in writing, before you import, to rule on the classification of your product (19 CFR Part 177). Its ruling then binds CBP for the goods it describes, until it is modified or revoked. CBP's published rulings, searchable in its CROSS database, also show how similar goods were classified.
What TariffTrust does, and does not do
TariffTrust does not classify goods for you, and it does not issue binding classifications or customs determinations. It starts from the code you give it, found by you or by your broker, and calculates every US duty and fee that applies to that code, that country of origin and that date, each with its official source. A code that is incomplete, that the tariff in force does not have, or that names a special provision of Chapter 98 or a trade measure of Chapter 99 rather than a product is refused with what to do, never guessed.
Updated October 30, 2026. General information as of that date, not legal or customs advice: the official texts prevail, and a licensed customs broker can confirm what applies to your goods.