The duty paid depends on the customs classification of the imported merchandise, the customs valuation of the imported merchandise, and the applicable rate of duty. Imports are assigned a specific classification number, depending on the nature of the import. Applicable duty rates are associated with each classification number. Customs valuation determines the value that is assigned to an import for duty and statistical purposes. When this is not possible, alternative valuation methodologies specified in the Valuation Agreement are utilized.
Preferential rules vary depending on the preference program.
However, the WTO is now in the process of developing international rules of origin. Importers are responsible for the proper classification, valuation, and marking of goods that they import, for making truthful statements to government authorities, and for compliance with all laws affecting imports. Importers who make false statements or who intentionally violate U.S. customs laws may be subject to criminal prosecution.