The HTSUS (Harmonized Tariff Schedule of the United States) is the official reference that determines the duty rate and import requirements for every product imported into the United States. Every product is assigned a 10-digit HTS code, and that code maps to a duty rate and any applicable trade measures.

What does HTSUS stand for?

HTSUS stands for "Harmonized Tariff Schedule of the United States." It is the U.S. implementation of the international Harmonized System (HS) maintained by the World Customs Organization.

What is the difference between HTS and HTSUS?

"HTS" and "HTSUS" are used interchangeably in U.S. importing — both refer to the Harmonized Tariff Schedule of the United States. Strictly, an "HTS code" is the 10-digit number assigned to a product, while the "HTSUS" is the full schedule (the document) that contains all of those codes, notes, and duty rates.

What is the difference between the HTSUS and the international HS?

The Harmonized System (HS) is a 6-digit global standard used by 200+ countries and maintained by the World Customs Organization. The HTSUS adopts those first 6 digits unchanged, then adds 2 digits for the U.S. tariff rate line (digits 7–8) and 2 statistical digits (digits 9–10), making a 10-digit code. So the first 6 digits of a U.S. HTS code match the rest of the world; the last 4 are U.S.-specific.

What is the difference between the HTSUS and Schedule B?

The HTSUS is used to classify goods being imported into the United States. Schedule B is used to classify goods being exported from the United States. Both share the same first 6 HS digits, but they are separate 10-digit systems: the HTSUS is administered by the USITC and CBP for imports, while Schedule B is administered by the U.S. Census Bureau for export reporting.

How many digits is an HTS code?

A full U.S. HTS code is 10 digits. The first 6 digits are the international HS subheading, digits 7–8 identify the U.S. tariff rate line, and digits 9–10 are the statistical suffix used for trade-data reporting.

How do I read a 10-digit HTS code?

Read it in layers. Example: 8517.13.00.00 (smartphones). "85" is the chapter (electrical machinery and equipment). "8517" is the heading (telephone sets and related apparatus). "8517.13" is the 6-digit international HS subheading (smartphones). "8517.13.00" is the 8-digit U.S. tariff rate line that carries the duty rate. "8517.13.00.00" adds the 2-digit statistical suffix.

How many chapters are in the HTSUS?

The HTSUS has 99 chapters organized into 22 sections. Chapters 1–97 cover physical goods by type (e.g., Chapter 1 live animals, Chapter 85 electrical machinery). Chapter 98 covers special U.S. classification provisions (such as goods returned or repaired). Chapter 99 covers temporary measures, including Section 301, Section 232, and IEEPA tariffs.

What are Chapters 98 and 99 of the HTSUS?

Chapter 98 contains special classification provisions unique to the U.S., such as U.S. goods returned, articles for repair, or government imports, which can reduce or eliminate duty. Chapter 99 contains temporary modifications — this is where additional tariffs like Section 301 (China), Section 232 (steel and aluminum), and IEEPA / reciprocal tariffs are applied on top of the base Chapter 1–97 rate.

Are Section 301 and Section 232 tariffs part of the HTSUS?

Yes — they are applied through Chapter 99 of the HTSUS. The base duty rate comes from the product’s Chapter 1–97 code, then a corresponding Chapter 99 heading (9903.xx) adds the Section 301, Section 232, or IEEPA tariff. The all-in rate an importer pays is the base rate plus every applicable Chapter 99 measure.

Who maintains and publishes the HTSUS?

The U.S. International Trade Commission (USITC) publishes and maintains the HTSUS. U.S. Customs and Border Protection (CBP) administers and enforces it at the border, including issuing binding classification rulings.

How often is the HTSUS updated?

The USITC publishes formal revisions periodically throughout the year, and changes can take effect on short notice — for example when new Section 301, Section 232, or IEEPA actions are announced. Because Chapter 99 measures change frequently, the duty rate on a code can shift between revisions, so it should be re-checked before each entry.

What are the General Rules of Interpretation (GRI)?

The General Rules of Interpretation are the six rules that govern how products are classified in the Harmonized System and HTSUS, applied in order. GRI 1 classifies by the terms of the headings and section/chapter notes. GRI 2 covers incomplete, unfinished, or mixed goods. GRI 3 resolves goods classifiable under multiple headings (most specific description, then essential character, then last in numerical order). GRI 4 handles goods most akin to others. GRI 5 covers cases and packaging. GRI 6 applies the same logic at the subheading level. You must work through them in sequence.

What is the difference between General, Special, and Column 2 duty rates?

Each HTS line lists multiple rates. The Column 1 "General" rate is the normal-trade-relations (MFN) rate that applies to most countries. The Column 1 "Special" rate is a reduced or duty-free rate for countries with a free-trade agreement or preference program (shown with letter codes like A, AU, CA, MX, KR). The Column 2 rate is a much higher rate that applies only to a small number of countries that do not have normal trade relations with the U.S. (currently Cuba, North Korea, Russia, and Belarus).

What is a Column 2 tariff rate and which countries does it apply to?

Column 2 rates are the penalty rates that apply to imports from countries without normal trade relations (NTR/MFN) status with the United States. As of 2026 these are Cuba, North Korea, Russia, and Belarus. Column 2 rates are typically far higher than the General (Column 1) rate.

How do I find the correct HTS code for my product?

Start from the product’s material and function, identify the chapter and heading, then work down through subheadings using the section and chapter notes and the General Rules of Interpretation. You can search the schedule with a free HTS code lookup, but for a defensible classification you should document the GRI reasoning and supporting CBP rulings — or request a binding ruling from CBP.

Who is legally responsible for getting the HTS classification right?

The importer of record bears the legal responsibility for declaring the correct HTS classification and exercising "reasonable care," even when a customs broker files the entry. Misclassification can lead to duty underpayment, penalties under 19 U.S.C. 1592, and CBP audits.

What happens if I use the wrong HTS code?

Using the wrong HTS code can mean underpaying or overpaying duty. Underpayment exposes the importer to penalties, interest, and back duties, and can trigger a CBP Form 28/29 inquiry or audit. Overpayment means leaving money on the table — it is often recoverable through a Post-Summary Correction (within 300 days) or a protest (within 180 days of liquidation).

Can I get a binding ruling on an HTS code?

Yes. Importers can request a binding classification ruling from CBP before importing. CBP publishes issued rulings in the CROSS (Customs Rulings Online Search System) database, which contains 200,000+ rulings that can be cited to support a classification.

Where can I look up an HTS code for free?

You can search the full Harmonized Tariff Schedule for free using the Tariffloop HTS Code Lookup, which returns the 10-digit code with its General, Special, and Column 2 duty rates and shows the Section 301 / 232 / IEEPA overlays in force for a chosen country of origin.

Guide

The HTSUS, explained

The Harmonized Tariff Schedule of the United States determines the duty rate on everything imported into the U.S. This guide explains how it is structured, how to read a 10-digit HTS code, and the rules that decide where a product is classified.

What is the HTSUS?

The HTSUS (Harmonized Tariff Schedule of the United States) is the official reference that determines the duty rate and import requirements for every product entering the United States. Every importable good is assigned a 10-digit HTS code, and that code maps to a duty rate plus any applicable trade measures. It is published by the U.S. International Trade Commission (USITC) and enforced at the border by U.S. Customs and Border Protection (CBP).

How a 10-digit HTS code is structured

The first 6 digits come from the international Harmonized System (HS) and are the same in 200+ countries. The U.S. adds 4 more digits: two for the tariff rate line and two for statistics. Here is the anatomy of 8517.13.00.00 (smartphones):

85Chapter— Electrical machinery & equipment
8517Heading— Telephone sets & related apparatus
8517.13HS subheading (international)— Smartphones
8517.13.00US tariff rate line— Carries the duty rate
8517.13.00.00Statistical suffix— Trade-data reporting

The 99 chapters

The schedule is organized into 22 sections and 99 chapters. Chapters 1–97 cover physical goods by type; Chapter 98 holds special U.S. provisions; and Chapter 99 is where temporary tariffs — Section 301, Section 232, and IEEPA — are layered on top of the base rate.

Ch. 1–5

Live animals; animal products

Ch. 16–24

Prepared foodstuffs; beverages; tobacco

Ch. 39–40

Plastics and rubber

Ch. 50–63

Textiles and apparel

Ch. 72–83

Base metals (steel, aluminum)

Ch. 84–85

Machinery and electrical equipment

Ch. 86–89

Vehicles, aircraft, vessels

Ch. 98–99

U.S. provisions & temporary tariffs

The General Rules of Interpretation (GRI)

Classification is not a guess — it follows six General Rules of Interpretation, applied strictly in order:

GRI 1 — classify by the terms of the headings and the section/chapter notes.
GRI 2 — incomplete, unfinished, or unassembled goods, and mixtures.
GRI 3 — goods classifiable under two or more headings: most specific description, then essential character, then last in numerical order.
GRI 4 — goods most akin to the closest matching goods.
GRI 5 — containers, cases, and packing materials.
GRI 6 — apply the same logic at the subheading level.

General, Special, and Column 2 duty rates

Every tariff line lists more than one rate. The Column 1 “General” rate is the normal (MFN) rate most countries pay. The Column 1 “Special” rate is reduced or duty-free for free-trade-agreement partners (shown with letter codes like A, AU, CA, MX, KR). The Column 2 rate is a much higher penalty rate that applies only to countries without normal trade relations — currently Cuba, North Korea, Russia, and Belarus.

HTSUS vs. HS vs. Schedule B

The HS is the 6-digit global standard. The HTSUS extends it to 10 digits for U.S. imports. Schedule B is a separate 10-digit system, run by the Census Bureau, for U.S. exports. All three share the same first 6 digits.

HTS Code Lookup →

Search the full schedule with live duty rates.

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Trade Glossary →

Definitions for every customs term in this guide.

HTSUS frequently asked questions

Everything importers ask about the Harmonized Tariff Schedule, answered.

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