US tariff schedules distinguish among rough (paddy) rice, husked (brown) rice, semi-milled, and wholly milled white rice, each falling under a different HTS heading with potentially different duty rates and TRQ applicability. Importers must confirm the exact degree of milling with the foreign supplier and ensure the commercial invoice and phytosanitary certificate accurately reflect the product's processing stage.

USDA APHIS requires phytosanitary certificates for rice imports to address risks from pests such as rice weevil and diseases like rice blast. Rough rice faces the most stringent scrutiny because it retains the hull, which can harbor soil and plant material. Milled rice generally presents lower phytosanitary risk but still requires documentation confirming pest-free status from the country of origin.