All of the imports and export codes used by the United States are based on the Harmonized Tariff System (HTS). The HTS assigns 6-digit codes for general categories. Countries which use the HTS are allowed to define commodities at a more detailed level than 6-digits, but all definitions must be within that 6-digit framework.

The U.S. defines products using 10-digit HTS codes. Exports codes (which the U.S. calls Schedule B) are administered by the U.S. Census Bureau. Import codes are administered by the U.S. International Trade Commission (USITC).