As the basis of the Harmonized System, the nomenclature is the structure on which the HS is built.

The Nomenclature, which is international and versatile, allows the classification of more than 5,000 groups of goods, identified by a six-digit code and classified according to a legal and logical structure. This HS code is a 6-digit code, designating by pairs of digits the position of a reference in the Harmonised System. The first pair corresponds to the chapter number, the next pair to the position within the chapter and the last pair to the subheading, which is the highest level of precision (i.e. 1517.10 - Margarine, excluding liquid margarine). Over the last 30 years it has become a universal customs language for the classification of goods and accounts for 98% of international trade.