Product classification
HS code for Ammonium alum: 2833.30
Alums.
Classification of ammonium alum under HS 2833.30
Ammonium alum, chemically known as ammonium aluminum sulfate, is classified under HS code 2833.30. This code is specifically reserved for "Alums." Chapter 28 of the Harmonized System deals with inorganic chemicals, precious metals, and rare-earth metals. Alums are a distinct class of double sulfates, typically consisting of a monovalent cation, such as ammonium or potassium, and a trivalent metal, such as aluminum, chromium, or iron. Ammonium alum is a white crystalline double sulfate frequently used in water purification, tanning, and as a mordant in the textile dyeing process. The classification under 2833.30 is determined by the chemical structure of the product as a double salt. Under the General Rules of Interpretation, a specific heading for a chemical group like "Alums" takes precedence over more general headings for sulfates. This ensures that double salts are not confused with simple single salts. The product is often traded in its dodecahydrate form, but the classification remains the same regardless of the degree of hydration, as long as it maintains the chemical identity of an alum.
- Covers
- Ammonium aluminum sulfate
- Ammonium alum crystals
- Ammonium alum powder
- Technical grade ammonium alum
- Dodecahydrate ammonium alum
- Also under 2833.30
- Alum Stone (deodorant)
- Water Treatment Alum (various suppliers)
- Mordant Alum (textile dyes)
- Styptic Pencil (shaving products)
Codes often confused with 2833.30
Common mistake. Ammonium alum is frequently misclassified under HS code 2833.22, which is the specific code for aluminum sulfate. While ammonium alum contains aluminum sulfate as part of its double salt structure, it is chemically distinct. It may also be confused with 2833.29, which covers other sulfates. However, because 2833.30 specifically mentions alums, it is the only correct classification for this double salt.
Top exporters and importers of HS 283330 (the code used for ammonium alum), 2025
In 2025, the largest exporter of HS 283330 (the code used for ammonium alum) in UN Comtrade data was China, with 30% of world exports; the largest importer in UN Comtrade data was the United States, with 29% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Figures cover everything classified under HS 283330, not only ammonium alum.
Top exporters 2025 · share of world exports
- 1 China $5.9M 30% of world exports
- 2 Mexico $3.4M 17% of world exports
- 3 India $2.0M 10% of world exports
World total: $20M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United States $8.3M 29% of world imports
- 2 Thailand $2.6M 8.9% of world imports
- 3 India $2.3M 8.0% of world imports
World total: $29M Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM code for ammonium alum
Brazil classifies ammonium alum under NCM 2833.30.00: HS 2833.30 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about ammonium alum
What is the HS code for Ammonium alum?
The HS code for Ammonium alum is 283330 (Alums). The HS code for ammonium alum is 2833.30, which is the category for all alums.
How do I classify Ammonium alum for customs?
Ammonium alum is classified under HS code 283330 — Alums. This is a 6-digit subheading level code.
Can ammonium alum be classified as a fertilizer?
No, while it contains ammonium, ammonium alum is classified as an inorganic chemical under Chapter 28 and not as a fertilizer in Chapter 31.
Which countries are the top exporters of ammonium alum (HS 283330)?
In 2025, the top exporters of HS 283330 (the code used for ammonium alum) in UN Comtrade data were China ($5.9M, 30% of world exports), Mexico ($3.4M) and India ($2.0M). World exports came to about $20M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of ammonium alum (HS 283330)?
In 2025, the top importers of HS 283330 (the code used for ammonium alum) in UN Comtrade data were the United States ($8.3M, 29% of world imports), Thailand ($2.6M) and India ($2.3M). World imports came to about $29M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Is the HS code for Ammonium alum the same in all countries?
The base HS code 283330 for Ammonium alum is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.
What is the NCM code for ammonium alum in Brazil?
In Brazil, ammonium alum (HS 283330) is classified under NCM 2833.30.00.