HTS Code (Harmonized Tariff Schedule) (HTS)

Definition

The Harmonized Tariff Schedule of the United States is the classification system that assigns a numeric code to every imported product. The HTS code determines the duty rate and any applicable trade restrictions for the goods.

Why it matters

An incorrect HTS classification can mean an incorrect duty calculation. Classification often requires judgment, so it is a field that should be reviewed by a person against the source document, not assumed or rushed.

How the HTS code is structured

A U.S. HTS number is 10 digits. The first six are the heading and subheading of the international Harmonized System (HS). Digits 7 and 8 complete the 8-digit U.S. subheading, which is the line where the tariff schedule prints the duty rate. Digits 9 and 10 are a statistical suffix. The suffix sorts imports for trade statistics and is not part of the schedule's legal text. Cotton T-shirts show the split: the schedule prints the 16.5% general rate on subheading 6109.10.00, and the 10-digit numbers under it carry no rate of their own (2026 schedule, Revision 21, in effect October 9, 2026). Extra duties work at the same level. The Section 301 list under heading 9903.88.01 names 8-digit subheadings of China-origin goods.

The classification process and where it goes wrong

The tariff schedule's General Rules of Interpretation set the method: classification follows the terms of the headings and the section and chapter notes. In practice the code turns on what the product is, what it is made of and, for some headings, how it is used. Country of origin is a separate question. Origin, together with the code, decides which rate column and which Chapter 99 headings apply. A commercial invoice description like "industrial parts" or "clothing accessories" does not determine the code. The person who classifies the goods needs the invoice, the packing list, and sometimes the product specification. Errors that put a wrong code on an entry include using a prior shipment's code without checking whether the product changed, accepting the shipper's declared code without verification, and choosing a general heading when a more specific heading describes the goods. If a wrong code underpays duty, CBP can bill the difference with interest when it liquidates the entry, which is its final computation of the duty owed.

Section 301 and HTS classification risk

Section 301 duties on China-origin goods are separate headings in Chapter 99 of the tariff schedule. The list-based duties, which CBP began assessing on July 6, 2018, each sit in a heading tied to a list of product codes, so the HTS code decides whether the duty applies and at what rate. In the 2026 schedule, Revision 21, in effect October 9, 2026, the list headings in force add 7.5%, 25%, 50% or 100% to the duty in the product's own subheading. Goods under a granted exclusion have their own headings, which add nothing. A newer Section 301 duty took effect on July 24, 2026. It adds 12.5% to products of China under heading 9903.05.31, with exceptions the schedule lists. A wrong code can put the goods on the wrong list or on no list, and the importer then underpays or overpays the Section 301 duty. CBP can bill an underpayment when it liquidates the entry. For high-volume importers, ensuring the HTS code is correct on every entry is a direct cost-control function, not just a compliance exercise.