How to Find the Right HS Code — Classification Basics and Practical Tips

The HS Code is the reference point for duty rates, trade statistics, and FTA origin determination across the entire trade process. Yet few teams can confidently name the exact HS Code for their own product. This guide covers how the HS Code is structured and a practical approach to finding the correct one.

How an HS Code is structured

The Harmonized System (HS), set by the World Customs Organization (WCO), is internationally standardized at the first 6 digits.

• First 2 digits (Chapter): broad category — e.g., Chapter 84 (machinery), Chapter 85 (electrical equipment)
• First 4 digits (Heading): sub-category
• First 6 digits (Subheading): the smallest internationally common unit — every country uses the same code up to this point.
• Digits 7–10: country-specific breakdown — Korea uses a full 10-digit code (HSK, the Integrated Tariff Schedule), and these trailing digits vary by country.

In short: the first 6 digits are internationally recognized, but actual import/export declaration and duty rate application require your own country's full 10-digit code.

A practical sequence for finding the right code

1. Clearly define the product's material, function, and use first: HS classification follows the General Rules of Interpretation (GRI), which classify based on what an item is made of and what it's used for. Classification is often impossible from a product name alone — "a plastic product" doesn't even pin down the right Chapter.
2. Search candidates by keyword: use a tool like our HS Code Lookup to search by product keyword and review candidate codes. Korean customs data also includes the English product name (per WCO nomenclature), so cross-checking with English keywords helps when the Korean description is ambiguous.
3. For mixed-material or set items, classify by "essential character": items made of multiple materials, or sold as a set, are classified under GRI 3's "essential character" rule — a plastic case containing a metal tool set, for example, is classified based on the set's core function (the tools), not the case.
4. When still unclear, use an advance classification ruling: for ambiguous, high- value, or high-volume items, the safest path is to request an official advance classification ruling from customs before shipping — if a classification is found incorrect after the fact, it can trigger back-duties and penalties.

Why getting this right matters

A single HS Code determines:

• Duty rate: not just the base rate, but whether FTA preferential rates, WTO agreement rates, or flexible tariffs like anti-dumping duties apply.
• Import/export requirements: certain codes trigger separate quarantine, certification, or licensing requirements.
• FTA origin determination: rules of origin (such as tariff classification change criteria) are defined at the HS Code level — get the code wrong, and the origin determination itself becomes meaningless.

Practical checklist

• Work out material, function, and structure in concrete detail before searching for a code — vague descriptions like "parts" or "miscellaneous goods" make accurate classification impossible.
• Try both Korean and English keywords in HS Code Lookup to widen your candidate search.
• Once you've confirmed the 10-digit code, check not just the base rate but FTA/WTO and flexible tariff details as well.
• For ambiguous or newly imported items, eliminate risk with an advance customs ruling.
• When entering the HS Code on a Commercial Invoice or Packing List, always use the confirmed 10-digit code exactly (see our Commercial Invoice guide for details).