Heading 2833

Sulfates; alums; peroxosulfates (persulfates)

21 declarable lines

Heading 2833 covers sulfates, alums and peroxosulfates (persulfates), which are inorganic salts formed from sulfuric acid or its peroxo form. The heading is split first by type: sodium sulfates, other sulfates, alums, and peroxosulfates. Within those groups the lines separate products by the metal or ammonium cation present, and sodium sulfates are further split between disodium sulfate (salt cake, anhydrous, other) and remaining sodium sulfates.

Products in this heading

Copper sulfate (bluestone) used in agriculture and plating
Magnesium sulfate (Epsom salt)
Aluminum sulfate used in water treatment
Salt cake grade sodium sulfate for detergents and pulp
Nickel sulfate for electroplating baths
Barium sulfate used as a filler and contrast agent
Sodium persulfate and ammonium persulfate used as oxidizers
Potassium aluminum alum used in water treatment and dyeing

How to choose the right subheading

Identify the anion: plain sulfate, alum, or peroxosulfate (persulfate).
For sulfates, identify the cation or metal: sodium, magnesium, aluminum, nickel, copper, barium, zinc, and so on.
For sodium sulfates, decide between disodium sulfate and other sodium sulfates.
For disodium sulfate, decide whether the goods are salt cake, anhydrous, or other.
For persulfates, decide between sodium persulfate and other persulfates, then name the cation such as potassium or ammonium.

Often confused with

Sodium sulfite and sodium thiosulfate
These are sulfites and thiosulfates, not sulfates.
Heading 2832
Sodium sulfide
Sulfides belong to a separate heading.
Heading 2830
Sodium chlorate and sodium perchlorate
Chlorates and perchlorates are classified by the halogenate anion, not by sulfate.
Heading 2829
Ammonium nitrate
Nitrates sit in heading 2834, separate from sulfates.
Heading 2834
Sodium hydroxide (caustic soda)
This is a hydroxide, not a sulfate salt.
Heading 2815

Frequently asked questions

What is the HTS code for copper sulfate?

Copper sulfate is classified under 2833.25.00.00, which carries a general (MFN) rate of 1.4%.

What is the duty on Epsom salt (magnesium sulfate)?

Magnesium sulfate falls under 2833.21.00.00 and the general (MFN) rate is 3.7%.

How do I classify sodium persulfate?

Sodium persulfate is classified under 2833.40.20.00 at a general (MFN) rate of 3.7%. Other persulfates go under 2833.40.60.10, 2833.40.60.20 or 2833.40.60.50 depending on the cation, all at 3.1%.

Guide written from the official schedule text. Rates quoted are general (MFN) rates; check the line page for trade agreement rates and the classification of your exact product.