Chapter (HTSUS)
A chapter is a 2-digit grouping of related headings within the HTSUS. The schedule contains 97 active chapters (Chapter 77 is reserved; Chapters 98 and 99 contain special provisions). Each chapter begins with legally binding chapter notes that define scope, exclude goods, or establish classification conditions — and these notes must be evaluated before heading text is applied under GRI 1.
In Detail
Chapters are organized within 22 sections. Most sections contain multiple chapters grouped by industry or material type: Section XVI, for example, contains Chapter 84 (machinery and mechanical appliances) and Chapter 85 (electrical machinery and equipment). The chapter structure follows the international Harmonized System framework maintained by the WCO, which all member countries must follow at the 6-digit level.
Chapter notes perform four primary functions: defining terms used in headings (e.g., defining “machines” or specifying what constitutes “plastics” for chapter purposes), excluding goods from the chapter, including goods that heading text alone might not capture, and cross-referencing goods that belong in other chapters or sections. These notes carry the same legal weight as heading text under GRI 1 and must be consulted first.
Chapters 98 and 99 are structurally different from Chapters 1–97. Chapter 98 covers special import situations such as returned goods and personal exemptions. Chapter 99 contains all temporary duty provisions — Section 301, Section 232, and IEEPA tariff overlays. Classification in Chapter 99 is additive: a product retains its Chapter 1–97 classification and separately receives any applicable Chapter 99 overlay codes.
Classification Significance
Correct chapter identification is a prerequisite for reading the right chapter notes, which are required for accurate GRI 1 analysis. A classifier who assumes a chapter without systematically evaluating competing chapters risks missing a dispositive exclusionary note — or failing to apply an inclusionary note that would redirect the goods to a different chapter entirely.
How Kanon Handles This
Kanon's corpus parser ingests all 97 chapters’ notes and parses them into structured condition trees. For any product under analysis, all chapter notes relevant to candidate headings are evaluated before heading text is applied. Exclusionary, inclusionary, and definitional chapter notes are represented as structured conditions — not free text — so no chapter note can be silently bypassed.