HS code: the international foundation
The Harmonized System (HS) is a 6-digit product classification code maintained by the World Customs Organization (WCO). It is used by over 200 countries to identify products in international trade. The 6-digit structure is organized into 97 chapters: digits 1-2 are the chapter, digits 3-4 are the heading, and digits 5-6 are the subheading. The HS code identifies what a product is at an international level — it tells customs the broad product family, but it does not include duty rates or country-specific measures.
- 6 digits: internationally harmonized across 200+ countries.
- Identifies the product family, not the duty rate.
- The starting point for classification in any country.
- The same 6-digit code means the same product family everywhere.
US HTS code: the US tariff extension
The US Harmonized Tariff Schedule (HTS) extends the 6-digit international HS code to 10 digits. Digits 7-10 are the US national extension. They contain US-specific duty rates, additional tariff columns, statistical reporting codes, and measures such as Section 301 and Section 232 tariffs. The USITC HTS is the official US tariff schedule and is the authoritative source for US import duty rates and tariff measures.
- Digits 1-6: international HS heading (shared globally).
- Digits 7-8: US statistical subheading (often for statistical precision).
- Digits 9-10: US duty rate and additional tariff subcodes.
- Additional tariff columns: Section 301 (China), Section 232 (steel/aluminum), and trade program rates.
Why 6 digits alone are not enough for US imports
Using only the first 6 digits of an HS code for a US import entry is not sufficient. The 6-digit international heading identifies the product family but does not include the US duty rate or the additional tariff treatment. The 10-digit US HTS code is required because the specific duty rate is set at the 8 or 10-digit level, Section 301 and Section 232 additional tariffs are listed at the 10-digit level, the correct trade program rate may depend on the full 10-digit code, and statistical reporting codes are at the 10-digit level.
- A 6-digit HS code tells customs the product family — not the duty rate.
- Section 301 additional tariffs are listed at the 10-digit level.
- US duty rates are set at the 8 or 10-digit subheading level.
- Providing only 6 digits may result in a default code being applied by the carrier.
How to use the USITC HTS database
Use hts.usitc.gov to find the correct 10-digit US HTS code for a product. Start with the international 6-digit HS heading that matches the product. Then narrow down using chapter notes, heading notes, and the tariff text to find the correct 8, 9, or 10-digit subheading. Read the duty rate columns and additional tariff columns to identify the applicable rates for the product and origin.
- Step 1: Identify the 6-digit international HS heading using product material and function.
- Step 2: Read the chapter notes and heading notes in USITC HTS for classification guidance.
- Step 3: Narrow to the 8-digit subheading that matches the product construction and use.
- Step 4: Read the duty rate column for the applicable rate.
- Step 5: Check the additional tariff columns for Section 301 and Section 232 rates.
- Step 6: Note the statistical reporting code (digits 9-10) for the entry.
The workflow for a US import
For a US import, the classification workflow has two steps. First, identify the 6-digit international HS heading using the product description, material, and function. Second, extend the code to the full 10-digit US HTS by reading the USITC HTS database and finding the correct subheading for the product. Use the full 10-digit HTS code on the commercial invoice and customs entry.
- Step 1 — HS candidate: Identify the 6-digit international HS heading.
- Step 2 — HTS verification: Extend to the 10-digit US HTS in USITC HTS.
- Step 3 — Duty lookup: Read the duty rate column for the applicable rate.
- Step 4 — Additional tariff check: Check Section 301 and Section 232 columns for the product and origin.