HTS Code Lookup: The Complete Guide

An HTS code is a 10-digit number that tells U.S. Customs exactly what you’re importing — and determines how much duty you owe. Getting it right is not optional: the importer of record is legally required to classify goods correctly under 19 USC 1484, and errors can mean back-duties, fines, and delayed shipments.

What Is an HTS Code?

Harmonized Tariff Schedule (HTS) code: A 10-digit product classification number assigned under the Harmonized Tariff Schedule of the United States (HTSUS), maintained by the U.S. International Trade Commission (USITC). Every physical product imported into the United States must be assigned an HTS code on the formal entry document (CBP Form 3461 or its electronic equivalent in the ACE Portal). The code determines the duty rate, any applicable trade remedy tariffs, quota restrictions, and eligibility for preferential trade program rates such as those under USMCA or the Generalized System of Preferences (GSP).

The HTS system is built on top of the international Harmonized System (HS), a product nomenclature developed by the World Customs Organization (WCO) and used by more than 200 countries. The first six digits of any HTS code are internationally standardized — a product classified under Chapter 85 (electrical equipment) in the U.S. will also sit under Chapter 85 in the EU, Japan, and Mexico. The final four digits are country-specific: digits 7–8 represent the U.S. subheading, and digits 9–10 are the “statistical suffix” used for U.S. Census trade data reporting.

Why this matters for importers: The difference between two HTS codes can be the difference between a 0% duty rate and a 25% duty rate — or between a straightforward clearance and a shipment held for FDA examination. The stakes are high enough that the U.S. imports roughly $3.2 trillion in goods annually (CBP Fiscal Year 2023 Trade Statistics), and duty collection depends entirely on accurate classification across millions of entry lines.

How the HTS Code System Is Structured

The 10-digit HTS code breaks down as follows:

The HTSUS is organized into 22 Sections and 99 Chapters. Section and chapter notes — the legal text that precedes each chapter’s table — are binding and often contain the rules that determine where a product is classified. Ignoring the notes is one of the most common professional mistakes.

The Six General Rules of Interpretation (GRIs)

Classification is not guesswork. The HTSUS follows six General Rules of Interpretation that must be applied in sequence:

1. GRI 1 — Heading Terms and Notes: Classification is first determined by the heading description and any legal section or chapter notes. Most products are classified here.
2. GRI 2 — Incomplete or Unfinished Goods: Unfinished or incomplete articles are classified as the finished article if they have the essential character of the finished good. Mixtures and combinations are also addressed.
3. GRI 3 — Multiple Possible Headings: When a product could fall under two or more headings, apply the most specific heading; if equally specific, classify by the component that gives the product its essential character.
4. GRI 4 — Most Similar Goods: If no heading fits, classify under the heading for the most similar goods.
5. GRI 5 — Packing and Cases: Containers and packing materials are classified with their contents if they are the type normally sold together.
6. GRI 6 — Subheading Comparison: The same rules apply at the subheading level, comparing only subheadings at the same level of indentation.

In practice, GRI 1 resolves the majority of classifications. GRI 3 becomes critical for composite articles — products made of multiple materials or components — and is the source of most classification disputes.

Step-by-Step: How to Look Up an HTS Code

Step 1 — Describe Your Product Precisely

Before you open any database, write out a complete product description that covers: material composition (by percentage if a mixture), primary function or end use, manufacturing method (if relevant), and any distinguishing features. Vague descriptions produce vague results. “Electronic device” won’t get you far; “portable lithium-ion battery pack, 20,000 mAh, used to charge mobile phones, no radio transmission capability” will.

Step 2 — Go to hts.usitc.gov

The official HTSUS database at hts.usitc.gov is maintained by the U.S. International Trade Commission and is updated for each trade law change, tariff modification, and trade agreement. Use the keyword search to find candidate headings. Cross-reference results against the chapter index to confirm you’re in the right section.

Step 3 — Read the Section and Chapter Notes

This step is non-negotiable. Chapter notes define terms, exclude specific products, and establish classification rules that override the plain-language heading descriptions. Chapter 84, for example, contains notes defining what qualifies as a “machine” versus a product that belongs in another chapter. If the notes exclude your product, the heading doesn’t apply — no matter how similar the description sounds.

Step 4 — Apply the GRIs in Order

Work through the six GRIs systematically. Identify the heading that best describes your product under GRI 1. If ambiguity exists, document which GRIs you applied and why. This documentation becomes your defense in a CBP audit.

Step 5 — Check for Additional Duty Programs

Once you have a candidate code, check:

• Section 301 tariffs (China-origin goods): CBP’s USTR Section 301 lists
• Antidumping/Countervailing Duty (AD/CVD) orders: enforcement.trade.gov/adcvd
• Trade agreement preferential rates: USMCA, CAFTA-DR, etc., available in the “Special” rate column of the HTSUS

Step 6 — Request a Binding Ruling If Uncertain

For high-value or high-volume products where classification is ambiguous, request a binding ruling from CBP at rulings.cbp.gov. CBP is required to respond within 30 days for most requests. A binding ruling is legally enforceable — if you follow it and CBP later disagrees, the agency cannot assess retroactive penalties for that classification.

Step 7 — Record and Maintain Your Classification

Document your classification rationale, keep it in your import records, and update it when the HTSUS changes (typically January 1 of each year). Under 19 CFR Part 163, importers must retain entry records for five years from the date of entry.

The Legal Framework: Your Responsibility as Importer

Under 19 USC 1484, the importer of record must exercise “reasonable care” in preparing or supervising the preparation of import entries. CBP’s reasonable care standard — detailed in the Customs Informed Compliance Publication on the topic — explicitly includes proper HTS classification as part of that obligation.

19 USC 1592 governs penalties for entry errors. The statute creates three tiers:

• Negligence: Penalty up to the domestic value of the merchandise; in practice, typically limited to unpaid duties plus interest for first offenses with prior disclosure.
• Gross negligence: Penalty up to four times the unpaid duties or 40% of the dutiable value.
• Fraud: Penalty up to the domestic value of the merchandise.

CBP’s penalty mitigation guidelines, published in 19 CFR Part 171 Appendix B, allow substantial reduction for voluntary prior disclosure before an investigation begins. If you discover a classification error in your historical entries, filing a prior disclosure under 19 CFR 162.74 limits your exposure to unpaid duties plus interest — no penalty above that.

One practical note: CBP has five years from the date of entry to assess additional duties under 19 USC 1505(b). A misclassification identified in year one can result in auditors reviewing all entries back to year one of that five-year window.

Real-World Classification Examples

Example 1 — The 51% Rule for Textiles

A U.S. company imports woven scarves made of 55% polyester and 45% cotton. The physical item looks identical to a cotton scarf sold by a competitor. The competitor’s product is classified under HTS 6214.20 (scarves of wool or fine animal hair or cotton) at a duty rate of 11.4%. Your polyester-majority scarf falls under HTS 6214.30 (scarves of man-made fibers) at 6.3%. Same product category, different duty rates — because material composition by weight controls classification for most textile articles under Section XI notes.

Example 2 — Composite Articles Under GRI 3

An importer brings in a carrying case pre-packed with a laptop. Under GRI 5, cases designed for a specific article and sold with that article are classified with it. The laptop itself classifies under HTS 8471.30.0100 (portable automatic data processing machines) at a 0% duty rate. The case on its own might be dutiable. Combined, the entire package takes the laptop’s classification — saving the importer the case duty.

Example 3 — Section 301 Overlay

An electronics manufacturer imports printed circuit board assemblies from China. The base HTS rate for the product is 0% under HTS 8534.00.0020. However, those goods are subject to a 25% Section 301 tariff under List 3 of the USTR’s China tariff actions. The importer who focuses only on the base HTSUS rate and misses the Section 301 column will significantly underpay duties — triggering back-assessments when CBP’s ACE system flags the discrepancy at liquidation.

Common HTS Classification Mistakes

Relying on a Supplier’s Suggested Code

Overseas suppliers often provide HTS codes on commercial invoices. These are almost always the HS code used in their country of export — which shares the first six digits with the U.S. HTS code but may differ in the last four digits. More importantly, the supplier has no legal liability under U.S. customs law for how their code is used. You do.

Using Last Year’s Code Without Verifying Updates

The HTSUS is revised annually, typically effective January 1. Chapter notes change, headings are reorganized, and duty rates are modified by Presidential proclamations throughout the year. A code that was correct in January may be invalid by March. Always verify against the current edition at hts.usitc.gov.

Ignoring Section 232 and Section 301 Columns

The base “General” duty rate column is not the total duty. For steel and aluminum products, Section 232 tariffs apply under separate proclamations. For goods of Chinese origin, Section 301 tariffs add 7.5%, 25%, or higher rates on top of the base rate. Both are tied to HTS codes — check every column, not just “General.”

Classifying by Appearance Rather Than Function

Two products that look identical can have different classifications based on function or intended use. A stainless steel bowl sold in a kitchen store may classify differently from an identical stainless steel bowl marketed as industrial processing equipment. The chapter notes and heading terms determine classification based on what the product is, not what it looks like.

Tools and Resources for HTS Code Lookup

For specialized imports — pharmaceuticals, food products, automotive parts, chemicals — working with a broker who knows your product category is valuable beyond just classification. You can browse brokers by specialty or search all CBP-licensed customs brokers to find someone with relevant experience. If your shipments enter through a specific port, you can also [browse by U.S. port of entry](https://customsbrokerindex.com/ports-of-entry