1. What the HS is
The Harmonized Commodity Description and Coding System is maintained by the World Customs Organization.
It provides a common nomenclature for traded goods, harmonised at the six-digit level across its members.
2. The structure
Twenty-one sections.
Ninety-seven chapters at the two-digit level.
Headings at four digits.
Subheadings at six digits.
Beyond six digits, each country’s national schedule subdivides further. The United States uses ten digits, the EU uses ten, China uses ten, ASEAN countries use eight.
3. The six General Interpretative Rules
The GIRs are the legal rules for classification, and they are applied in order.
GIR 1
Classification is determined by the terms of the headings and any relative section or chapter notes.
This is the primary rule, and most classification is resolved here. The notes are legally binding and often override the heading text.
GIR 2
Covers incomplete or unfinished articles presented unassembled, and mixtures and combinations.
An unassembled article that has the essential character of the assembled article is classified as the assembled article.
GIR 3
Covers goods classifiable under two or more headings.
3(a): the heading providing the most specific description prevails.
3(b): mixtures and composite goods are classified by the component giving the essential character.
3(c): failing that, the heading occurring last in numerical order.
GIR 4
Goods that cannot be classified under rules 1 to 3 are classified under the heading for goods most akin.
GIR 5
Covers packing materials and containers.
GIR 6
Extends the rules to subheading level, comparing subheadings at the same level.
4. Why the notes matter
The section and chapter notes are binding. They exclude goods from headings and include them in others, often contrary to the heading’s plain reading.
An importer who classifies by the heading’s description alone, without reading the notes, is likely to be wrong on the difficult products.
5. The national level
The six-digit code is harmonised. The national digits are not.
The same product may carry different codes in different countries because the national subdivisions differ.
This is why a Chinese export declaration code cannot simply be reused for the destination import declaration.
6. The consequence
The HS code determines:
The tariff rate.
The regulatory requirements.
The origin criteria under free trade agreements.
The statistics.
An error at six digits can change all four.
7. Common errors
Classifying by name
Chapter notes may exclude.
Ignoring GIR 2
Machine shipped unassembled classified as parts.
Assuming the code is universal
Only to six digits.
Not checking the national schedule
National subdivisions carry requirements.
Reusing a code from a supplier
The supplier’s classification may be wrong.
8. The practical approach
Read the chapter and section notes for the candidate headings.
Apply the GIRs in order.
Check the national schedule for the destination.
Where the classification is material, consider an advance ruling.
9. Closing view
The HS system is a legal instrument with defined rules, and classification is an application of those rules rather than a lookup.
The rules are not difficult. Applying them systematically is what most importers skip.
*This article is based on the Harmonized Commodity Description and Coding System maintained by the World Customs Organization, including the General Interpretative Rules and the section and chapter notes. Exporters and importers should confirm classification with the relevant customs authority.*