Harmonized System Code (HS Code)
The international product classification that decides your duty rate.
The Harmonized System is maintained by the World Customs Organization and used by almost every trading country. The first six digits mean the same thing everywhere. The digits after that are added by each country. The United States uses ten digits, the EU eight or ten.
The code sets the duty rate. It also sets which rule of origin applies, because preferential rules are written for each tariff heading. Give at least six digits on a commercial invoice, and the destination country's full code if you know it.
At destination, the importer is responsible for the classification. Getting it wrong costs money either way. Too high and you pay too much duty. Too low and you owe the difference plus interest when customs finds it.
Also called: HTS code, tariff code, commodity code.