Ammonium Sulphate 21-0-0-24S
Caprolactam-grade crystalline and compacted granular AS, 21% N / 24% S
Ammonium sulphate is the cheapest nitrogen-plus-sulphur fertilizer in the trade and most of it is a by-product: caprolactam plants, coke ovens and flue-gas desulphurisation units make it, which is why the price tracks the chemical industry as much as the fertilizer season. Two physical forms move under one analysis. Caprolactam-grade crystalline AS is a white to off-white crystal at 20.5–21% nitrogen and 24% sulphur, fine (typically 0.5–2 mm), and priced as the base product for compound NPK manufacture, blending plants that granulate, and markets that broadcast it. Compacted granular AS is the same crystal pressed and screened to 2–4 mm, steel-grey to buff in colour because of the compaction aids and the coke-oven fraction, and it is the direct-application and bulk-blending product because it spreads and blends with urea and DAP without segregating. The specification is short: nitrogen 20.5% minimum (21% on the best caprolactam lots), sulphur 24% minimum, moisture 0.5% maximum on crystal and 1% on granular, free acid 0.05% maximum as sulphuric acid, and size; colour is a guide to the source, not to the analysis.
Buy AS where the crop wants sulphur alongside nitrogen — oilseeds, maize, sugar cane, coffee, oil palm and rice on sulphur-deficient soils — and where its acidifying effect suits an alkaline soil; it is also the standard nitrogen source in compound NPK plants that need sulphur in the formula. China is the dominant exporter, loading at Huanghua, Qingdao, Tianjin and Zhanjiang in Handysize and Supramax parcels; the desk saw a 30,000 MT Huanghua-to-Mumbai stem in September 2026, and the same lanes run into Brazil, Vietnam, Indonesia, the Philippines and East Africa. China's HS 3102.21 export declarations for 2025 are not available in UN Comtrade at the time of writing, so we price from the loadings we see rather than from a table; excluded origins are not offered. CBIL brokers crystalline and compacted AS against independent certification of N, S, moisture, free acid and size at load, in bulk vessel parcels, 50 kg PP bags and 1 MT jumbo bags, on FOB, CFR and CIF terms.
Need the ship as well? Our chartering desk prices bagged fertilizer freight on LaycanDesk.
Indicative reference
$140–210 USD / MT
as at September 2026
Reference level only — not an offer, and reviewed quarterly. Levels shown are as at September 2026. Firm pricing is quoted per RFQ, subject to volume, terms and inspection.
Typical Specification
Specifications are indicative and adjusted to the agreed contract and destination requirements. Final spec confirmed on COA / SGS.
Available Grades
Applications
- Oilseeds, maize & sugar cane
- Coffee, oil palm & tea
- Compound NPK manufacture
- Bulk blending
- Alkaline & sulphur-deficient soils
Category
Agriculture & Fertilizers
Incoterms
FOB · CFR · CIF
Pricing basis
USD / MT
Inspection
SGS / Intertek at load port
Ammonium Sulphate 21-0-0-24S — buyer questions
Crystalline or granular ammonium sulphate?
Crystalline if you granulate it yourself into compound NPK, run a blending plant that can handle fines, or serve a market that broadcasts fine product; it is the cheaper base grade. Compacted granular at 2–4 mm if you spread it directly or blend it with granular urea, DAP and MOP, because the fine crystal segregates and cakes in a granular blend. The analysis is the same; the form decides.
Does the colour mean anything?
It tells you the source, not the quality. Caprolactam-grade crystal is white; coke-oven and FGD product runs off-white to grey; compacted granular is steel-grey to buff because of the binder and the feedstock mix. A grey lot at 21% N and 24% S is the same fertilizer as a white one. Judge on the certificate, and specify colour only if your retail market demands it.
Why buy AS rather than urea?
For the sulphur, and for the soil. AS carries 24% sulphur, which oilseeds, maize, cane and plantation crops on leached or sulphur-deficient soils need and urea does not supply, and it acidifies rather than alkalises, which helps on calcareous ground. Per unit of nitrogen alone urea is cheaper; per unit of nitrogen plus sulphur delivered where both are needed, AS often wins.
What loadings and parcel sizes do you work from China?
Handysize and Supramax bulk parcels of 25,000–55,000 MT from Huanghua, Qingdao, Tianjin and Zhanjiang, plus bagged container business for smaller distributors. Lanes run into India, Brazil, Vietnam, Indonesia, the Philippines and East Africa. Tell us the discharge port and whether you want crystal or compacted, and we will match a loading to the laycan.
Ready to source Ammonium Sulphate?
Send your quantity, specification, preferred Incoterms and destination port. We'll verify supply and respond with a workable offer — usually within one business day.
Have Ammonium Sulphate to sell? Submit an offer — we'll match it against live buyer demand.
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