HS 310221 · Ammonium sulphate
Get the code right at quotation time, not at customs.
Misclassifying HS 310221 on the commercial invoice walks the cargo into the wrong duty rate, the wrong rebate column, and a customs hold that costs days of demurrage to clear. This page gives you the WCO heading, the product it most often covers, the China VAT export rebate rate, the US Section 301 status, the supplier provinces that ship it, and practitioner buying notes for first-time importers.
For an explanation of how the WCO Harmonized System is structured, what each digit means, and why misclassification is the most common landed-cost error first-time buyers make, see the HS code glossary entry.
Key facts
The numbers a buyer needs at the quotation stage. Verify each against the live source before invoicing; rates and rebate columns move.
| WCO heading | Ammonium sulphate |
|---|---|
| Chapter | 31, Fertilisers |
| Industry segment | Fertilisers |
| Chinese name | 硫酸铵 |
| China VAT export rebate | 0% Source: China State Taxation Administration (国家税务总局), 2025 schedule. Subject to change. |
| US Section 301 | Not currently listed Source: USTR Section 301 List 1 / 2 / 3 / 4. Verify against the current schedule. |
| Major Chinese supplier provinces | Henan, Shandong, Jiangsu, Hebei |
Buying notes
Ammonium sulfate (NH4)2SO4 ships in 50 kg PP bags or 1 t big bags. Two production routes in China: caprolactam by-product (the dominant route, around 70% of supply) and synthetic from ammonia plus sulfuric acid. The caprolactam by-product carries trace caprolactam impurities that some downstream blenders specify against; insist on a recent COA. Granular grade trades at a premium over crystalline because of blending compatibility with urea and DAP in compound fertiliser plants. Section 301 0% on US import.
Common end uses
The applications that drive most of the global tonnage under this code.
- Nitrogen-sulfur fertiliser (21-0-0 plus 24% S)
- Soil acidifier on alkaline soils
- Animal feed supplement (limited)
- Flame retardant in textiles
- Pharma and food precipitation agent
Where to read next
For grade-by-grade buying notes, freight maths, supplier-tier pricing, and a worked landed-cost example, the Ammonium sulphate cornerstone hub covers the full sourcing chain.
For the structure of the HS / Harmonized System, what each digit means, and why misclassification costs landed-cost margin, see the HS code glossary entry.
Need a quote on this code? Send us the HS code, the destination port, and the tonnage and we will quote FOB China and CIF / DDP landed including the current Section 301 and rebate position.
Read next
Other codes in the same chapter and the references behind them
Hub
Ammonium Sulfate from China, sourcing, grades, packaging, and landed cost
Operator-grade reference for buying ammonium sulfate from Chinese suppliers. Caprolactam by-product vs synthetic vs coke-oven by-product, granular vs crystalline, big bags, and the structural Chinese supply position.
CAS
CAS 7783-20-2 Ammonium sulfate
Not classified as DG. Ships in 25 to 50 kg bags, 1 t big bags, or bulk vessel. Most Chinese supply is caprolactam by-product, marginal cost
HS Code
HS 310540 NPK mineral fertilisers
Chapter 31, NPK mineral fertilisers. China VAT rebate 0%.
HS Code
HS 310280 UAN urea-ammonium-nitrate solution
Chapter 31, UAN urea-ammonium-nitrate solution. China VAT rebate 0%.
Glossary
HS Code, Harmonized System Code
A six-digit international product classification code used by customs authorities worldwide to identify goods, assess duties, and apply trade controls. Countries extend the six-digit base with additional digits for tariff and statistical purposes (10-digit HTS in the US, 8-digit CN code in the EU, 10-digit AHECC in Australia).
Glossary
VAT Rebate, VAT Export Rebate
The Chinese government refund of value-added tax paid on inputs used to produce goods for export. Set as a percentage of the export FOB value, varying by HS code and adjusted by the State Administration of Taxation. Rebates of 13%, 9%, 6%, or 0% are typical for chemical exports. The rebate is the single largest policy lever the Chinese government uses to influence which chemicals are exported and at what scale.
Free download
Free PDF: thirty-point factory audit checklist used on every chemical-park site visit, mapped against the HS-code-leading Chinese producers.