HTS Classification for Chemicals and Plastics: Raw Materials, Polymers, and Finished Products

Chemicals and Plastics: A Vast Classification Landscape

The chemical and plastics sectors together account for a substantial share of U.S. imports, with hundreds of billions of dollars crossing borders annually. The HTS chapters covering these products — Chapters 28 through 39 — represent one of the most technically demanding areas of tariff classification because they require knowledge of chemistry, material science, and manufacturing processes. Chapter 28 covers inorganic chemicals, Chapter 29 covers organic chemicals, Chapter 30 covers pharmaceuticals (addressed in our separate pharma guide), Chapter 31 covers fertilizers, Chapter 32 covers tanning and dyeing extracts, Chapter 33 covers essential oils and cosmetics, Chapter 34 covers soaps and detergents, Chapter 35 covers albuminoidal substances and glues, Chapter 36 covers explosives, Chapter 37 covers photographic goods, Chapter 38 covers miscellaneous chemical products, and Chapter 39 covers plastics and articles thereof. Each chapter has its own classification logic and hierarchy of specificity.

Inorganic and Organic Chemicals: Chapters 28 and 29

Inorganic chemicals in Chapter 28 include elements, acids, oxides, hydroxides, salts, and other inorganic compounds. The classification is straightforward in principle — you identify the chemical compound and find its heading. Sodium hydroxide is 2815.11, hydrochloric acid is 2806.10, titanium dioxide is 2823.00. However, the purity of the product matters. Chapter 28 generally covers chemically defined compounds, meaning products of a defined chemical composition. Mixtures of inorganic chemicals may classify under Chapter 38 (miscellaneous chemical products) rather than Chapter 28. Organic chemicals in Chapter 29 follow a similar structure but with far more headings due to the vast number of organic compounds. The chapter is organized by chemical class: hydrocarbons (2901-2902), halogenated derivatives (2903), alcohols (2905-2906), acids and their derivatives (2915-2918), nitrogen-function compounds (2921-2929), and so on. Each chemical is classified based on its molecular structure. When a chemical does not fit into a named heading, it falls into residual headings like 2942 (other organic compounds).

Plastics in Primary Forms: Chapter 39 Headings 3901-3914

Chapter 39 is divided into two main parts. The first part (headings 3901-3914) covers plastics in primary forms — polymers, copolymers, and resins before they are shaped into articles. Heading 3901 covers polymers of ethylene (polyethylene, including LDPE, LLDPE, and HDPE). Heading 3902 covers polymers of propylene (polypropylene). Heading 3903 covers polymers of styrene (polystyrene, ABS). Heading 3904 covers polymers of vinyl chloride (PVC). Heading 3907 covers polyacetals, polyesters (including PET), polycarbonates, and epoxide resins. Heading 3908 covers polyamides (nylons). Heading 3909 covers amino-resins, phenolic resins, and polyurethanes. Classification within these headings depends on the specific polymer and its form — granules, powder, liquid, dispersion, or solution. Primary forms include liquids and pastes, blocks, lumps, powders, granules, and flakes. Note 6 to Chapter 39 defines what constitutes 'primary forms' and is critical for correct classification.

• Polyethylene (LDPE, HDPE, LLDPE): 3901
• Polypropylene: 3902.10-3902.30
• Polystyrene: 3903.11-3903.19
• ABS (acrylonitrile-butadiene-styrene): 3903.30
• PVC: 3904.10-3904.50
• PTFE (Teflon): 3904.61
• PET (polyethylene terephthalate): 3907.61-3907.69
• Polycarbonate: 3907.40
• Nylon (polyamide-6, polyamide-6,6): 3908.10
• Polyurethane: 3909.50
• Silicones in primary forms: 3910

Plastic Articles: Chapter 39 Headings 3916-3926

The second part of Chapter 39 (headings 3916-3926) covers articles of plastics. Heading 3916 covers monofilaments, rods, and profiles. Heading 3917 covers tubes, pipes, hoses, and fittings. Heading 3918 covers floor coverings. Heading 3919 covers self-adhesive plates, sheets, film, and tape. Heading 3920 covers other plates, sheets, film, and foil — not self-adhesive and not reinforced. Heading 3921 covers plates, sheets, and film that are cellular (foamed) or reinforced. Heading 3922 covers baths, shower trays, sinks, and sanitary ware. Heading 3923 covers articles for the conveyance or packing of goods — bottles, boxes, bags, and containers. Heading 3924 covers tableware and kitchenware. Heading 3925 covers builders' ware. Heading 3926 is the residual heading for other articles of plastics. The distinction between headings 3920 and 3921 is particularly important: 3920 covers non-cellular, non-reinforced film and sheet, while 3921 covers cellular or reinforced material. This distinction can have significant duty implications.

Specialty Chemicals: Chapters 32-38

Between the base chemicals of Chapters 28-29 and the polymers of Chapter 39, several chapters cover specialty chemical products. Chapter 32 covers tanning extracts, dyes, pigments, paints, varnishes, inks, and putties. Chapter 33 covers essential oils, resinoids, perfumery, cosmetics, and toiletries — cosmetic imports are one of the fastest-growing categories, and the classification depends on the product type (skin care under 3304, hair care under 3305, oral care under 3306). Chapter 34 covers soap, organic surface-active agents, washing preparations, lubricating preparations, and waxes. Chapter 38 is the catch-all for miscellaneous chemical products, including insecticides (3808), finishing agents (3809), prepared rubber accelerators (3812), composite solvents (3814), hydraulic brake fluids (3819), diagnostic or laboratory reagents (3822), and biodiesel (3826). Chapter 38 also hosts heading 3824, one of the largest residual headings in the tariff, covering chemical products and preparations not elsewhere specified.

Common Classification Challenges for Chemicals and Plastics

1. Confusing chemically defined compounds with mixtures: Pure compounds classify in Chapters 28 or 29; mixtures usually classify in Chapter 38. The distinction depends on chemical composition, not packaging.
2. Misclassifying plastic articles by material instead of function: A plastic bottle classifies under 3923 (conveyance/packing), not under the heading for the plastic type it is made from.
3. Ignoring Note 1 exclusions: Many chapters have exclusion notes (e.g., Chapter 39 Note 2 excludes articles of Section XI that are textiles, even if made from plastic fibers).
4. Overlooking the primary forms definition: Plastic pellets, granules, and powders are 'primary forms' under Chapter 39 Note 6, but certain shaped or processed forms may no longer qualify.
5. Failing to identify copolymers correctly: A copolymer of ethylene and propylene classifies based on which monomer constitutes the greatest proportion by weight, not by the trade name.
6. Misclassifying chemical preparations: Industrial cleaning solutions, adhesives, and surface treatments are often mixtures that belong in Chapter 34, 35, or 38, not in the heading for their main chemical ingredient.

Trade Policy Impact on Chemical and Plastic Imports

Chemical and plastic imports are significantly affected by current trade policy. Section 301 tariffs on Chinese-origin chemicals and plastics add 25% to many product lines. Antidumping and countervailing duties (AD/CVD) apply to specific chemical and plastic products from certain countries — polyethylene retail carrier bags from several Asian countries, for example, face AD/CVD orders. The Section 232 tariffs on steel and aluminum do not directly affect chemicals and plastics, but downstream products made from tariffed materials may see price impacts. Environmental regulations, including EPA requirements under TSCA (Toxic Substances Control Act), add another layer of compliance that interacts with customs classification — certain chemicals require pre-notification to EPA before importation, and the classification triggers the relevant PGA flags in the entry process. Importers should ensure their HTS codes are accurate not only for duty purposes but for regulatory compliance across all partner government agencies.

“In chemistry, precision in naming compounds is essential. The same precision must apply to tariff classification. A single functional group difference between two organic compounds can mean entirely different headings, duty rates, and regulatory requirements.”

— CBP Laboratory and Scientific Services Directorate