HTS Code Lookup: How to Find a US Tariff Code (and HTS vs HS)

2026-11-12

Every duty estimate I've ever done starts with the same question: what is this thing's tariff code? Get the code wrong and everything after it is wrong too, including the base rate, any Section 301 or Section 232 add-ons, and sometimes whether a duty applies at all. This post covers how I look up a US HTS code, how the HTS relates to the international HS code, and where a lookup tool stops being enough.

I built DutyCite's HTS lookup and duty calculator around one idea: every rate it shows comes with the official source it came from. So I'll point to those same sources here.

Disclaimer: This post is general information. It isn't customs brokerage, legal advice or a binding classification. If you need a classification you can rely on, request a binding ruling from U.S. Customs and Border Protection (CBP) or work with a licensed customs broker.

HS vs HTS: same first six digits, different jobs

The Harmonized System (HS) is maintained by the World Customs Organization. The WCO describes it as a nomenclature of "more than 5,000 commodity groups; each identified by a six digit code," used by "more than 200 countries and economies" as the basis for their customs tariffs (WCO).

The Harmonized Tariff Schedule of the United States (HTS or HTSUS) is the US tariff, published by the U.S. International Trade Commission (USITC) (USITC HTS). It keeps the HS six digits and adds US-specific detail:

The HTS General Statistical Notes describe the 10-digit "statistical reporting number" as "the 8-digit subheading number with the appropriate 2-digit statistical suffix," and they treat those suffixes as statistical annotations rather than legal text (HTS General Notes). In practice:

• The duty rate lives at the 8-digit level. On Nov 12, 2026 the live HTS listed the General rate for 4819.10.00 as Free (USITC HTS).
• You still report all 10 digits on the entry.
• A 6-digit HS code from your supplier is only a starting point. Another country's national digits after the sixth often don't match the US ones.

How I do an HTS code lookup, step by step

1. Describe the product the way the tariff does

The tariff cares about what something is: what it's made of, what it does and how it's put together. Brand names and marketing copy don't help. "Eco shipping mailer" means nothing to the HTS. "Printed box of corrugated paperboard" does.

2. Find the chapter and heading, then read the notes

Search by keyword in the USITC HTS or in DutyCite's /hts lookup, but don't stop at the first match. Read the section and chapter notes. They often exclude whole product families or send them somewhere else.

3. Apply the General Rules of Interpretation

Classification is governed by the General Rules of Interpretation (GRI). GRI 1 says classification is determined "according to the terms of the headings and any relative section or chapter notes." Titles are "for ease of reference only" (HTS GRI). The later rules handle the hard cases:

• GRI 2 covers unfinished or unassembled articles and mixtures.
• GRI 3 covers goods that could fit two headings. The most specific description wins (3(a)), then "essential character" (3(b)), then the heading that comes last in numerical order (3(c)).
• GRI 5 covers cases and packing.
• GRI 6 applies the same logic at the subheading level.

4. Pick the 8-digit line, then the 10-digit suffix

Once the heading is settled, walk down the indents to the 8-digit rate line and choose the statistical suffix that fits.

5. Check Chapter 99 before you trust the rate

This is the step people skip. The base rate on the 8-digit line is often not the whole duty. Extra duties under Section 301, Section 232 and other programs live in Chapter 99, and they're keyed to your Chapter 1–97 code and the country of origin. For example, the same Free-rated corrugated box from China picks up two separate Section 301 duties in the current HTS. I walk through that in the China duty walkthrough and explain the layers in what a stacked tariff rate includes.

Where HTS lookups go wrong

• Using the supplier's code as-is. Their 6 digits may be right. Their last 4 usually aren't US digits.
• Classifying by use when the heading is by material, or the reverse. Read the heading text literally.
• Ignoring chapter notes. Many "obvious" matches are excluded by a note.
• Stopping at the base rate. See step 5.
• Assuming last year's code is still valid. The USITC publishes revisions during the year. The edition I checked for this post was 2026 HTS Revision 23.

When a lookup isn't enough: binding rulings

A lookup tool, including mine, gives you a well-sourced starting point. If money or compliance depends on the answer, the formal route is a binding ruling from CBP under 19 CFR Part 177 (eCFR, 19 CFR Part 177). CBP explains the process on its rulings page, and you can search past rulings in the Customs Rulings Online Search System, CROSS, to see how CBP has classified similar goods. Requests can be submitted through eRulings. A licensed customs broker can also prepare and file entries for you.

How DutyCite fits in

I designed DutyCite so you can check its work:

• The HTS lookup helps you find a code and its rate in the USITC schedule.
• The calculator returns the full stack: the base rate plus Section 301 and Section 232, then the MPF and HMF. Each line has its own as-of date and source.
• Developers can get the same data from an API or MCP server. The docs and pricing pages have the details.

If you're new to the duty side, the next post to read is how to calculate US import duty in 2026.

Facts in this post were checked on Nov 12, 2026, against 2026 HTS Revision 23. The HTS changes during the year, so check the live schedule before you import.

References

1. World Customs Organization, "What is the Harmonized System (HS)?" https://www.wcoomd.org/en/topics/nomenclature/overview/what-is-the-harmonized-system.aspx
2. U.S. International Trade Commission, Harmonized Tariff Schedule search. https://hts.usitc.gov/
3. USITC, HTS General Notes (incl. General Statistical Notes), current release. https://hts.usitc.gov/reststop/file?release=currentRelease&filename=General%20Notes
4. USITC, HTS General Rules of Interpretation, current release. https://hts.usitc.gov/reststop/file?release=currentRelease&filename=General%20Rules%20of%20Interpretation
5. eCFR, 19 CFR Part 177, Administrative Rulings. https://www.ecfr.gov/current/title-19/chapter-I/part-177
6. U.S. Customs and Border Protection, Rulings. https://www.cbp.gov/trade/rulings
7. CBP, Customs Rulings Online Search System (CROSS). https://rulings.cbp.gov/
8. CBP, eRulings. https://erulings.cbp.gov/