How HS Classification Actually Works: The Six GRI Rules Explained

Every customs classification in every WCO member country follows the same six rules, the General Rules of Interpretation (GRI). When two headings both seem to describe your product, the GRI decides the winner. Understanding them is the difference between classifying products and guessing at them.

GRI 1: Start with the Words

Classification is determined by the text of the headings and the section and chapter notes. Nothing else comes first. If a chapter note says “this chapter does not cover X,” then X does not go in that chapter, no matter how well the heading reads. GRI 1 resolves most everyday products: a wool sweater falls in heading 6110 because that heading says sweaters, and the chapter notes do not exclude it.

Practical implication: always read the notes before the heading text. Classifiers who skip the notes classify by vibe, and notes exist precisely to break the intuitive answer.

GRI 2: Unfinished Goods and Mixtures

GRI 2 covers two situations:

2(a), incomplete articles. A product with the essential character of a finished article classifies as the finished article, even if shipped incomplete or unassembled. An unassembled bicycle frame with all parts in one shipment is still a bicycle for classification. This rule matters enormously for e-commerce: knock-down furniture and kit products often classify as the completed good.

2(b), mixtures and combinations. A mixture of two or more materials or substances classifies as if it were the material or substance that gives it its essential character, when GRI 1 does not resolve it. A juice drink that is 60 percent apple and 40 percent pear leans on this rule.

GRI 3: When Three Headings Fit

The workhorse rule for real products, applied in order:

3(a), most specific description wins. A phone case shaped like a stuffed animal competes between “toys” and “cases for telephones.” The heading that most precisely describes the item prevails over a catch-all. Headings that describe goods by function or purpose usually beat generic material headings.

3(b), essential character. If 3(a) does not decide it, the product classifies as the material or component that gives it its essential character. For a set of tools sold in a plastic carrying case, the tools, not the case, usually give the set its character. For a retail set of a razor plus blades, ask which part the buyer is actually paying for.

3(c), last in numerical order. If both 3(a) and 3(b) fail, the heading appearing last in numerical order wins. This is a tiebreaker of last resort, rare in practice.

One guardrail: GRI 3 applies only when headings each cover part of the goods. If one heading already covers the whole product, GRI 1 alone decides, and you skip straight past this rule.

GRI 4: The Nothing-Fits Rule

Goods that no heading adequately covers classify under the heading of the goods to which they are most similar. In practice GRI 4 is nearly extinct, because the schedule’s scope plus notes catch almost everything, including novel products. New tech usually lands somewhere concrete: a smartwatch classifies by its function as a timepiece with communication features, not through “most similar” gymnastics.

GRI 5: Containers and Packing

5(a), specially shaped containers that are sold with an article and are suitable for long-term use (a camera case, a silver casket) classify with the article. 5(b), ordinary packing that is not reusable classifies with the contents. The cardboard box around your goods does not get its own classification, and neither does the blister pack.

GRI 6: Now Do It Again at Subheading Level

Once the heading is fixed, the comparison repeats at subheading level, using the same rules mutatis mutandis, but comparing subheadings at the same level under the chosen heading. Anker-level detail lives here: “of cotton” versus “of man-made fibres” at the six-digit level, then the eight-digit statistical breakout within the winning branch.

Putting It Together

A worked example: a bluetooth speaker wrapped in leatherette, sold with a charging dock in the same box.

1. GRI 1: heading 8518 covers loudspeakers. Chapter 85 notes do not exclude it. Heading resolves.
2. GRI 5(b): the leatherette wrap and retail box classify with the speaker.
3. GRI 2(b) or 3(b): the dock is secondary and does not change the essential character of the set.
4. GRI 6: descend into the 8518 subheadings to the 10-digit line for the entry.

That is the whole game: notes first, then heading text, then the tiebreakers, then repeat at subheading level. Our HS Code Finder runs the heading search against the official HTS and shows candidates so you can walk this logic yourself. For what happens when the walk goes wrong, see what happens if you use the wrong HS code.

This article is general information, not legal advice. Confirm classifications on specific goods with a licensed customs broker or CBP.