Commodity code (HS Code / CN) – how to avoid classification errors? [2026]

Every item in the world – from a live chicken to a microprocessor – has its number in the customs system. This is Customs Tariff Code. For the customs officer, "Leather shoes" is an abstract term. For them, it is `6403 91 13`.

The correct code determines: 1. Customs duty rate (e.g. 0%, 12%, 25%). 2. VAT rate. 3. Sanitary/licensing requirements (e.g. veterinary, military).

An error in the code is the easiest way to cause problems.

HS, CN, TARIC – what do these numbers mean?

Understanding the code structure is fundamental:

• HS Code (6 digits): Harmonized System. An international standard (worldwide). The first 6 digits of the goods code are (theoretically) the same in Poland, USA, China, and the UK.
• CN (8 digits): Combined Nomenclature. Used in the EU for exports. Extends HS by 2 digits.
• TARIC / UKGT (10 digits): Used for IMPORT. Specifies specific duty rates and trade policy measures (e.g., anti-dumping).

Example: A Polish company uses an 8-digit code (CN) in exports. The UK importer uses a 10-digit code (UK Global Tariff).

How to determine the commodity code?

Never guess. 1. ISZTAR 4 (Polish tariff browser) – for checking export codes. 2. UK Global Tariff (UKGT) – for checking import codes in the UK.

Note: Codes may differ! Although the first 6 digits (HS) should match, further digits in the UK and EU post-Brexit are diverging. Check the code in BOTH systems.

Most common errors

1. "I use the code given by my Chinese supplier"

This is a classic mistake. Chinese codes often do not match European ones. The Chinese supplier provides a code to ease export, not for you to import correctly. Always verify the code yourself.

2. "Parts for..."

Classifying everything as "Parts for machine X". The general rule states: if a part is a "general use item" (e.g. screw, bearing, gasket), classify it as a screw/bearing, not as a jet engine part. A screw is a screw.

3. Sets

You sell a "Gift Set: Mug + Coffee + Teddy Bear". What code? Classification rules for sets are complex (GIR 3b). Usually, the code is assigned by the item giving the set its "essential character". But if you misjudge what is "essential", customs may challenge the rate.

WIT (Binding Tariff Information)

If you have doubts and fear risks (e.g. customs duty is 0% or 10% depending on interpretation), apply for WIT (BTI - Binding Tariff Information). This is an official decision that "locks in" your code. The customs officer at the border cannot challenge it. Valid for 3 years. It is worth doing for the company’s key products.

Summary

Commodity classification is the responsibility of the Entrepreneur, not the Customs Agency (although the agency assists). If the agency enters the wrong code (because it was provided by you), you will pay the penalty.

Check your codes in the ISZTAR and UKGT systems. It’s free and could save you thousands of zlotys.

What the current official guidance means in practice

For operational work, the current procedural rules, declaration fields and relief conditions should be checked directly against the official guidance. For this topic, the core reference points are European Commission, GOV.UK / HMRC.

Official sources

• EU Commission (Customs procedures) — European Commission, 2026-03-04
• UK GOV (Importing into the UK) — GOV.UK / HMRC, 2026-03-04
• GOV.UK: Customs Declaration Service — GOV.UK / HMRC, 2026-03-04