What Is an HS Code? Structure and How to Look It Up

To work out landed cost you need the duty rate, and that rate is set by the goods' HS code. Since one code drives not just duty but import requirements like quarantine and certification, a wrong classification leads to back-duty or clearance delays.

This guide helps anyone new to classifying goods understand HS code structure, look one up correctly, and avoid misclassification risk.

What Is an HS Code?

The HS code (Harmonized System) is an international, standardized product-classification code created by the World Customs Organization (WCO). The first six digits are common worldwide; from the seventh, each country subdivides. Korea extends it to 10 digits as HSK (HS of Korea).

HS Code Structure: Chapter, Heading, Sub-heading

So the first six digits are international-common, while Korea's actual duty rate and import requirements are set on the 10-digit HSK.

Why It Matters

• Sets the duty rate: the same item can carry very different rates (0 to 50%+) depending on classification.
• Import requirements: quarantine, certification, and permits hinge on the HS code.
• FTA origin: preferential duty and origin determination also rely on the HS code.

How to Look Up an HS Code

• Narrow candidates by product name, use, material, and function.
• Confirm the code and duty rate on a customs classification portal or lookup tool.
• If unsure, apply for an advance classification ruling from customs to fix it in advance.

What Happens if You Misclassify

• Back-duty and penalties: declaring a lower rate by mistake invites later collection.
• Clearance delays: missing a requirement-bound item triggers inspection and rework.
• Loss of FTA benefit: a mistaken origin determination can forfeit preferential duty.

This guide is for general information. Actual classification, rates, and requirements vary by item and timing. Confirm with customs resources and a licensed customs broker.