HTS Code Classification: A Practical Guide for US Importers (With Common Mistakes to Avoid)

The HTS code on your customs entry determines your duty rate, your eligibility for trade agreement benefits, and your exposure to antidumping duties. Here's how classification works, how to find the right code, and the five mistakes importers make most often.

Every product imported into the United States must be assigned a 10-digit HTS (Harmonized Tariff Schedule) code. That code determines the duty rate, whether antidumping or countervailing duties apply, and how the goods are tracked statistically. It is not a formality — it is a legal classification decision that the importer of record is responsible for getting right.

HTS classification is the importer of record's legal responsibility — not CBP's and not automatically the broker's. The code determines your duty rate, AD/CVD exposure, and trade agreement eligibility. Misclassification, even unintentional, can result in back-duty assessments, penalties, and CBP enforcement action.

Who Is Responsible for Getting It Right?

The importer of record is legally responsible for the accuracy of the HTS code on every customs entry. CBP does not pre-approve classifications before you file. If CBP later determines your code was wrong — whether through a CF-28 inquiry, a post-entry audit, or a formal examination — the importer pays the additional duties, plus potential penalties.

A licensed customs broker can and should advise on classification, but their role is advisory unless you have requested a specific classification service. If the broker files a code you provided without verification, that is generally the importer's exposure to manage.

How to Read an HTS Code

The 10-digit HTS code is structured in layers. Each layer narrows the classification:

1. Chapter (digits 1–2): The broadest category — e.g., Chapter 61 covers knitted or crocheted clothing
2. Heading (digits 3–4): Narrows within the chapter — e.g., 6109 covers T-shirts, singlets, and similar garments
3. Subheading (digits 5–6): The international standard level (harmonized with WTO members) — e.g., 610910 covers cotton T-shirts
4. US-specific (digits 7–8): Additional U.S. breakouts, often linked to trade agreements or duty rates
5. Statistical suffix (digits 9–10): U.S. Census reporting; no duty implications but required for accurate filing

The 6-digit subheading is the international standard — all WTO member countries classify goods the same way to that level. Digits 7–10 are U.S.-specific and can affect duty rates significantly.

How to Find the Right HTS Code

• CBP's CROSS database (rulings.cbp.gov): Searchable database of CBP binding rulings — the most authoritative classification reference available. Search by product description or keyword.
• USITC Tariff Browser (hts.usitc.gov): Official HTS schedule with duty rates, notes, and search tools. Start here to browse by chapter or heading.
• CBP's ACE filing system: Your broker will search these references when preparing your entry. Ask them to document their classification reasoning.
• Your licensed customs broker: For complex products — especially those that could plausibly fall under multiple headings — a broker's classification analysis is the appropriate step before committing to a code.

The 5 Most Common Classification Mistakes

1. Using the supplier's HTS code without verifying it. Overseas suppliers classify for their own export purposes — their code may not match U.S. import classification rules. Treat supplier-provided codes as a starting point, not a final answer.
2. Classifying by material rather than function. HTS General Rule of Interpretation 1 requires classification based on the heading that most specifically describes the article — which often means function, not composition. A plastic toy classified as 'plastic goods' instead of 'toys' will carry the wrong duty rate.
3. Missing Chapter 98 and 99 special provisions. Chapter 98 covers U.S. goods returned, goods for repair, and other special categories that can significantly reduce or eliminate duty. Chapter 99 covers temporary tariff modifications, including Section 301 tariffs. Missing these can mean overpaying duties.
4. Ignoring country-of-origin impact on duty rates. The HTS duty rate assumes normal trade relations. AD/CVD orders, Section 301 tariffs (China), and trade agreement benefits (USMCA, etc.) are all layered on top. The same HTS code carries different landed costs depending on where the goods were manufactured.
5. Not updating codes when product specs change. If a product is reformulated, reengineered, or sourced from a different supplier with different materials, the classification may change. Using last year's code for a modified product is a common audit finding.

Unsure Whether Your Current HTS Codes Are Correct?

What CBP Does When They Disagree With Your Classification

CBP has two main tools for challenging a classification after entry:

• CF-28 (Request for Information)|Informal inquiry — CBP asks for additional product information, technical specs, or manufacturer details. Not a formal finding, but requires a timely, documented response.
• CF-29 (Notice of Action)|Formal notice — CBP has made a classification determination and is issuing additional duties, penalties, or both. A protest can be filed within 180 days if you disagree.

If you receive either document, work through your customs broker immediately. Delays or inadequate responses to CF-28s are frequently cited as factors in subsequent penalty assessments.

The Binding Ruling Option

If you import a product regularly and are uncertain about its classification, you can request a binding ruling from CBP through the CROSS system. A binding ruling is CBP's official, written classification determination for your specific product. Once issued, both you and CBP are bound by it — meaning CBP cannot reclassify your goods and assess additional duties as long as your product matches the ruling description.

• Ruling requests are free and submitted through rulings.cbp.gov
• CBP typically responds within 30 days, though complex cases may take longer
• The ruling binds CBP — they cannot reclassify your product unless the ruling is revoked or modified
• The ruling is public — your classification rationale will be visible in the CROSS database
• Work with a licensed customs broker to prepare the ruling request — the product description and legal argument need to be precise