HS Chapter 28 covers inorganic chemicals, including organic and inorganic compounds of precious metals, of rare-earth metals, of radioactive elements, or of isotopes. The chapter spans 53 four-digit headings (28.01 to 28.53) and is the single largest HS chapter by Chinese chemical export tonnage. Caustic soda, sulphuric acid, soda ash, hydrogen peroxide, hydrochloric acid, titanium dioxide, ammonia, chlorine, and the bulk of metal oxides, hydroxides, halides, sulphates, and other inorganic salts all classify within Chapter 28.
Chapter structure
Chapter 28 organises inorganic chemicals broadly by element family, then by compound type:
| Range | Coverage |
|---|---|
| 28.01-28.05 | Halogens, sulphur, alkali and alkaline earth metals, rare-earth metals, mercury (the elemental substances) |
| 28.06-28.11 | Inorganic acids and inorganic oxygen compounds of non-metals (HCl, H2SO4, HNO3, H3PO4 and similar) |
| 28.12-28.13 | Halides and halogen oxides of non-metals; sulphides of non-metals |
| 28.14-28.17 | Ammonia and inorganic bases, caustic soda, potassium hydroxide, sodium peroxide, zinc oxide |
| 28.18-28.21 | Aluminium oxides and hydroxides, chromium compounds, manganese compounds, iron oxides |
| 28.22-28.27 | Cobalt, nickel, copper, zinc, manganese carbonates and chlorides |
| 28.28-28.33 | Hypochlorites, chlorates, perchlorates, sulphites, sulphates |
| 28.34-28.37 | Nitrites, nitrates, phosphites, phosphates, carbonates |
| 28.38-28.42 | Cyanides, fulminates, silicates, borates |
| 28.43-28.47 | Precious metal compounds, radioactive compounds, hydrogen peroxide |
| 28.48-28.53 | Phosphides, carbides, hydrides, nitrides, azides, miscellaneous |
The structure is logical for a chemist but can be a classification trap, many products fit two or more headings. A double salt (e.g. an aluminium-iron sulphate hydrate) might classify under 28.33 (sulphates) or under a more specific multi-element heading depending on the dominant chemistry. CBP and EU customs both publish guidance and binding rulings on common ambiguities.
Top-traded Chinese-export products in Chapter 28
| HS6 | Product | Approximate Chinese export volume (annual, indicative) |
|---|---|---|
| 28.15.11 | Sodium hydroxide solid | ~3-5 million MT |
| 28.15.12 | Sodium hydroxide solution | ~10-15 million MT |
| 28.07.00 | Sulphuric acid; oleum | ~5-8 million MT |
| 28.36.20 | Disodium carbonate (soda ash) | ~3-5 million MT |
| 28.23.00 | Titanium oxides (TiO2) | ~1.5-2 million MT |
| 28.06.10 | Hydrogen chloride / hydrochloric acid | ~2-3 million MT |
| 28.47.00 | Hydrogen peroxide | ~1 million MT |
| 28.14.10 | Anhydrous ammonia | ~2-3 million MT |
| 28.27.32 | Aluminium chloride | ~500,000 MT |
| 28.35.26 | Other phosphates of calcium (food grade) | ~300,000 MT |
The volumes are indicative, actual trade flows shift with VAT rebate cycles, anti-dumping measures, and demand cycles. UN Comtrade is the authoritative source.
Duty profile into US, EU, Australia
The MFN duty profile for Chapter 28 substances is generally low across developed-economy markets:
| Destination | Typical MFN range on Chapter 28 |
|---|---|
| US (HTS) | 0% to 6.5% |
| EU (TARIC) | 0% to 5.5% |
| Australia | 0% to 5% (often 0% under ChAFTA for Chinese origin) |
| Japan | 0% to 4% |
The duty story for Chinese-origin Chapter 28 substances is dominated by overlays rather than MFN:
- Section 301 (US), most Chapter 28 lines on List 1 or List 3 carry the 25% Section 301 duty
- Anti-dumping duties, active on a number of Chapter 28 substances from China (caustic soda has had AD orders in various jurisdictions; titanium dioxide has active investigations; certain aluminium and chromium compounds have AD orders)
- Countervailing duties, often paired with anti-dumping orders
A buyer importing caustic soda solid from China to the US in 2026 pays approximately: MFN 0% + Section 301 25% + (anti-dumping rate if applicable). The Section 301 alone moves the landed cost meaningfully.
Regulatory overlays specific to Chapter 28
Chapter 28 substances trigger overlapping regulatory regimes:
- REACH registration, applies to all Chapter 28 substances at >1 t/yr into the EU
- TSCA inventory, substantively all Chapter 28 commodity substances are TSCA active inventory
- IECSC listing, same; routine commodities are all listed
- IMDG Class 8 (corrosives), many Chapter 28 acids and bases are Class 8
- IMDG Class 5.1 (oxidisers), hydrogen peroxide, sodium chlorate, calcium hypochlorite from Chapter 28
- IMDG Class 6.1 (toxics), certain cyanides, arsenic compounds, mercury compounds from Chapter 28
For routine commodity Chapter 28 sourcing the regulatory overlays are well understood and the documentation chain is mature. For specialty Chapter 28 chemistry (precious metal compounds, rare earth compounds) the regulatory burden is higher and lead times longer.
VAT rebate sensitivity
Chinese export VAT rebates apply at the HS chapter level. Chapter 28 has been subject to several VAT-rebate adjustments since 2020:
- Caustic soda VAT rebate adjusted between 13% and 9% in different periods
- Hydrogen peroxide rebate adjusted with environmental policy changes
- Soda ash rebate stable at the higher tier through 2025
- Specific aluminium and titanium compounds subject to rebate cuts as part of strategic-resource policy
For volume buyers, the VAT rebate is a 4-7 percentage point sensitivity on the FOB Shanghai price. A rebate cut from 13% to 9% raises effective FOB by approximately 4%. Long-dated supply contracts should index for VAT rebate changes.
Operator note: the chapter sub-heading discipline
Chinese factories sometimes classify products at the 4-digit heading level (e.g. “Chapter 28.15” for caustic) rather than the full 6-digit subheading (28.15.11 for solid vs 28.15.12 for solution). The 4-digit classification is enough for routing through Chinese export customs but inadequate for destination customs entry. Always confirm the full HS6 (preferably HS8 or HS10 for the destination country) on the commercial invoice and packing list before the cargo ships. Otherwise the destination broker has to derive the classification, which slows clearance.
Related terms
HS Code is the underlying international 6-digit classification. Harmonized System is the global framework. Chapter 29 covers organic chemicals. Chapter 38 covers miscellaneous chemical products. Anti-dumping duty is the most common Chapter 28 overlay against Chinese-origin imports.