HTS Classification Fundamentals

The Harmonized Tariff Schedule of the United States (HTSUS) is based on the international Harmonized System (HS) maintained by the World Customs Organization. The HTS has 22 Sections and 99 Chapters. Classification follows a hierarchical structure: Section → Chapter (2-digit) → Heading (4-digit) → Subheading (6-digit, international) → Statistical suffix (8-10 digit, U.S.-specific). The first 6 digits are internationally harmonized.

Proper classification requires: (1) identifying the merchandise accurately — what is it, what is it made of, what is it used for; (2) reading the relevant Section and Chapter Notes; (3) applying the General Rules of Interpretation (GRI) in sequential order; and (4) if still unclear, consulting Additional U.S. Notes, Chapter/Section Notes, and CBP Ruling Letters. GRI 1 should always be applied first — classification must be determined according to the terms of the headings and any relative Section or Chapter Notes.

Chapter 98 and Chapter 99 contain special classification provisions. Chapter 98 includes provisions for returned U.S. goods (9801), goods exported for repair/alteration (9802), and other special categories. Chapter 99 contains temporary tariff modifications, such as those imposed under trade remedy actions (Sections 201, 232, 301). These provisions can significantly impact duty rates and should be checked for every entry.