HTS Code List: The Complete Guide for Importers

The HTS code list — formally called the Harmonized Tariff Schedule of the United States (HTSUS) — is the master reference that determines what duty rate every imported product pays when it enters the US. If you import goods commercially, every shipment you clear through customs is classified using this list, and getting it wrong can cost you more than the goods themselves.

This guide explains how the HTS code list is structured, how to find the right code for your products, what the legal framework requires, and where most importers go wrong.

What Is the HTS Code List?

Harmonized Tariff Schedule of the United States (HTSUS): A legally binding, government-published tariff classification system that assigns a unique 10-digit numerical code to every category of physical goods imported into the United States. The code determines the applicable duty rate, whether antidumping or countervailing duties apply, and which partner government agencies (FDA, USDA, EPA, etc.) have jurisdiction over the import.

The HTSUS is maintained by the U.S. International Trade Commission (USITC) and is published in full at hts.usitc.gov. It is updated annually, typically effective on January 1 of each year, with mid-year amendments as needed.

The schedule contains over 17,000 individual product categories organized into 97 chapters and 21 sections, covering everything from live animals (Chapter 1) to works of art (Chapter 97). In fiscal year 2023, U.S. Customs and Border Protection (CBP) processed over 37 million formal import entries, each one requiring at least one HTS classification.

The first six digits of every HTS code come from the international Harmonized System (HS), a product nomenclature system maintained by the World Customs Organization (WCO) and used by more than 200 countries. The final four digits are US-specific breakouts that reflect American trade policy, statistical tracking requirements, and treaty obligations.

How HTS Classification Works

Classification is not guesswork. CBP requires importers to follow a structured legal methodology called the General Rules of Interpretation (GRI), codified under 19 USC Chapter 4 and the HTSUS itself.

Step 1 — Identify the Chapter (Digits 1–2)

The HTSUS opens with a Section and Chapter structure. Products are grouped by material, function, or industry. A cotton T-shirt belongs in Chapter 61 (knitted apparel). A lithium-ion battery belongs in Chapter 85 (electrical machinery). Start by identifying what your product fundamentally is — its primary material or function determines which chapter applies.

Step 2 — Find the Heading (Digits 3–4)

Within each chapter, headings break products into more specific groups. Chapter 85, for example, contains separate headings for generators, transformers, batteries, and telecommunications equipment. Read each heading note carefully — CBP uses legal note language, not common commercial terms.

Step 3 — Determine the Subheading (Digits 5–6)

The six-digit subheading is where the international Harmonized System ends. At this level, your classification is synchronized with customs authorities in Canada, the European Union, Japan, China, and every other WCO member country. Most duty rate negotiations under trade agreements (USMCA, Korea-US FTA, etc.) reference this six-digit level.

Step 4 — Apply the US Breakouts (Digits 7–8)

The seventh and eighth digits add US-specific product detail. This is where CBP and the USITC track trade statistics and apply tariff-rate quotas. These breakouts may distinguish products by fiber content, size, processing method, or country of origin treatment.

Step 5 — Apply Statistical Suffixes (Digits 9–10)

The final two digits are statistical suffixes used by the Census Bureau for export/import data collection. They do not affect the duty rate, but they are required on all formal entry documents. An error in the statistical suffix is a minor violation; an error in digits 1–8 is a classification error with potential duty and penalty consequences.

Step 6 — Confirm Duty Rate and Special Programs

Once you have the 10-digit code, look up the duty column in the HTSUS:

• Column 1 — General: The standard MFN (most-favored nation) rate applied to imports from WTO member countries.
• Column 1 — Special: Reduced rates under trade agreements (USMCA, GSP, CBI, etc.).
• Column 2: The punitive rate applied to a small list of non-MFN countries.

Also check for Section 201, 232, and 301 additional duties — the trade remedy tariffs applied on top of the base rate for specific products or countries of origin.

The Legal Framework Behind HTS Classification

Classification decisions are not discretionary. Under 19 USC 1484, the importer of record is legally responsible for the accuracy of every entry, including the HTS code. This duty of reasonable care requires importers to research, document, and verify their classifications — not simply copy what a foreign supplier wrote on the invoice.

The specific methodology for classification is governed by 19 CFR Part 152, which instructs importers and CBP officers to apply the General Rules of Interpretation in sequence. The GRIs are hierarchical — you cannot skip to GRI 3 without first confirming GRI 1 and GRI 2 do not resolve the classification.

When a classification is genuinely ambiguous, importers have two formal options:

Binding Ruling (19 CFR Part 177): A written CBP ruling that legally binds CBP to a specific classification for described goods. Binding rulings are free to request through rulings.cbp.gov and typically take 30 days. Once issued, the ruling is publicly searchable and provides legal protection if CBP later disagrees with your classification.

Protest (19 USC 1514): If CBP liquidates your entry with a different classification than you used, you have 180 days to file a protest and request reconsideration.

CBP audits and verifies classifications through its Focused Assessment program. In fiscal year 2022, CBP issued more than $3.8 billion in unpaid duty bills through the audit process — a figure that underscores how seriously misclassification is pursued.

Real-World HTS Classification Examples

Understanding the structure in the abstract is one thing. Here is how it applies to common import scenarios.

These examples illustrate a critical point: the same product description can lead to different duty rates depending on material content, construction method, intended use, and country of origin. A “battery” is not one HTS code — it is dozens, spread across multiple chapters.

A licensed customs broker with the right specialty can identify these distinctions before your shipment arrives. Browse brokers by specialty — including electronics, automotive, pharmaceutical, food, and chemical specialists — to find one who knows your product category deeply.

Common HTS Classification Mistakes

Copying the Supplier’s Code Without Verification

Foreign suppliers assign HS codes based on their own country’s schedule, which diverges from the HTSUS at the 7-digit level. A Chinese supplier’s HS code is accurate to six digits in China — it is not a valid US HTS code, and the final four digits may be entirely wrong. Never import a supplier’s code directly onto your CBP entry without independent verification.

Using an Outdated Code

The HTSUS is a living document. CBP and the USITC revise it every year. New breakouts are added for emerging product categories (electric vehicles, for example, received updated chapter notes in recent revision cycles), and old codes are deleted or consolidated. A code that cleared without issue in 2022 may not exist in 2025, or may now carry additional trade remedies.

Misidentifying the Product’s Essential Character

Under GRI 3, when a product is a mixture or composite (a product that contains multiple materials or could fall in multiple headings), classification is based on the component that gives it its “essential character.” This is one of the most litigated classification questions in US customs law. A toy robot with electronic components could be classified as a toy (Chapter 95) or as electrical machinery (Chapter 85) depending on its primary function. Getting this wrong changes both the duty rate and which agency regulations apply.

Ignoring Chapter Notes and Section Notes

Chapter Notes and Section Notes are legally binding exclusions and inclusions that modify the plain meaning of headings. A product that appears to belong in Chapter 84 based on its heading description may be explicitly excluded by a Chapter Note and redirected to Chapter 90. Most classification errors that end up in litigation trace back to notes that were overlooked.

Failing to Check Trade Remedy Orders

Since 2018, Section 301 tariffs have added 7.5% to 25% on thousands of HTS codes covering goods of Chinese origin. Section 232 adds duties on steel and aluminum products. Section 201 applies safeguard tariffs on specific products like solar cells and washing machines. These are applied on top of the base rate. If you only check Column 1 — General, you may be significantly underestimating your landed cost. Check CBP.gov and enforcement.trade.gov for current orders and exclusions.

Tools and Resources for Finding HTS Codes

Official HTSUS: hts.usitc.gov — the authoritative source. Searchable by keyword or chapter. Includes all column rates, special program eligibility, and unit of quantity.

CBP Binding Rulings Database: rulings.cbp.gov — search thousands of prior rulings by product description, HTS code, or company name. Prior rulings are not binding on other importers, but they are persuasive authority and give you a clear picture of how CBP has classified similar products.

ACE (Automated Commercial Environment): CBP’s trade processing platform where entries are filed electronically. Accessible through trade software vendors like Customs City, Trade Facilitator, or broker-operated portals.

Schedule B Search Tool (Census Bureau): For exports, the Schedule B system (linked from the Census FTD website) cross-references HTS codes for export classification purposes. The first six digits are identical between HTS and Schedule B.

International Trade Administration: www.trade.gov provides country-specific trade data, tariff rates under trade agreements, and market access information.

NCBFAA: The National Customs Brokers & Forwarders Association of America publishes industry guidance, broker education resources, and advocacy positions on tariff policy.

A licensed customs broker: For any product you import in volume — more than a few shipments per year — professional classification by a licensed broker is often the most cost-effective investment you can make. A single misclassification audit can cost more than a year of broker fees. Search all CBP-licensed customs brokers on CustomsBrokerIndex to find one near you or near your port of entry.

If your goods arrive by sea or air at a major US port, the broker you choose should have experience at your specific port of entry. Browse by U.S. port of entry to filter by location. For reference on what full-service brokerage and warehousing looks like in practice, see our guide on 3PL with customs clearance and warehousing explained.

You can also browse brokers by state if you prefer a local partner with regional port expertise.

Frequently Asked Questions

What is an HTS code?

An HTS code (Harmonized Tariff Schedule code) is a 10-digit number assigned to every product imported into the United States. The code determines the duty rate, trade remedy applicability, and import regulations for that product. The first six digits follow the international Harmonized System, while the final four digits are unique to the US.

How does HTS classification work?

HTS classification follows the General Rules of Interpretation (GRI), a structured legal framework published in 19 USC Chapter 4. You start at the chapter level (2 digits), narrow to the heading (4 digits), then the subheading (6 digits), and finally the 8- and 10-digit US-specific breakouts. Each level refines what the product is and how it is taxed.

Who is required to classify goods with an HTS code?

Any person or business filing a formal entry for goods imported into the United States is required to provide an accurate HTS code under 19 USC 1484. This applies to importers of record, customs brokers filing on their behalf, and e-commerce sellers whose goods enter via formal entry. Informal entries under $800 use a simplified process but may still require classification.

What happens if you use the wrong HTS code?