Sulphates; alums; peroxosulphates (persulphates)

6-digit subheadings (10)

Official HS 2022 subheading texts. National tariff schedules subdivide these further (8-10 digit lines) and set the actual duty rates.

Chapter 28 classification notes

Classification certainty

The 6-digit level shown here is the internationally harmonised layer. Duty rates attach to national 8-10 digit tariff lines, which differ by country — use the duty calculator for lane estimates. For binding certainty, request a ruling from the destination customs authority.

Other headings in Chapter 28

• 2801 — Fluorine, chlorine, bromine and iodine
• 2802 — Sulphur; sublimed or precipitated, colloidal sulphur
• 2803 — Carbon; carbon blacks and other forms of carbon n.e.c.
• 2804 — Hydrogen, rare gases and other non-metals
• 2805 — Alkali or alkaline-earth metals; rare-earth metals, scandium and yttri…
• 2806 — Hydrogen chloride (hydrochloric acid); chlorosulphuric acid
• 2807 — Sulphuric acid; oleum
• 2808 — Nitric acid; sulphonitric acids
• 2809 — Diphosphorus pentaoxide; phosphoric acid; polyphosphoric acids, whethe…
• 2810 — Oxides of boron; boric acids
• 2811 — Inorganic acids and other inorganic oxygen compounds of non-metals; n.…
• 2812 — Halides and halide oxides of non-metals
• 2813 — Sulphides of non-metals; commercial phosphorus trisulphide
• 2814 — Ammonia; anhydrous or in aqueous solution
• 2815 — Sodium hydroxide (caustic soda); potassium hydroxide (caustic potash) …
• 2816 — Hydroxide and peroxide of magnesium; oxides, hydroxides and peroxides …
• 2817 — Zinc; oxide and peroxide
• 2818 — Aluminium oxide (including artificial corundum); aluminium hydroxide
• 2819 — Chromium oxides and hydroxides
• 2820 — Manganese oxides
• 2821 — Iron oxides and hydroxides; earth colours containing 70% or more by we…
• 2822 — Cobalt oxides and hydroxides; commercial cobalt oxides
• 2823 — Titanium oxides
• 2824 — Lead oxides; red lead and orange lead
• 2825 — Hydrazine and hydroxylamine and their inorganic salts; other inorganic…
• 2826 — Fluorides; fluorosilicates, fluoroaluminates and other complex fluorin…
• 2827 — Chlorides; chloride oxides and chloride hydroxides; bromides and bromi…
• 2828 — Hypochlorites; commercial calcium hypochlorite; chlorites; hypobromite…
• 2829 — Chlorates and perchlorates; bromates and perbromates; iodates and peri…
• 2830 — Sulphides; polysulphides whether or not chemically defined
• 2831 — Dithionites and sulphoxylates
• 2832 — Sulphites; thiosulphates
• 2834 — Nitrites; nitrates
• 2835 — Phosphinates (hypophosphites), phosphonates (phosphites), and phosphat…
• 2836 — Carbonates; peroxocarbonates (percarbonates); commercial ammonium carb…
• 2837 — Cyanides, cyanide oxides and complex cyanides
• 2839 — Silicates; commercial alkali metal silicates
• 2840 — Borates; peroxoborates (perborates)
• 2841 — Salts of oxometallic or peroxometallic acids
• 2842 — Salts of inorganic acids or peroxoacids, n.e.c. including aluminosilic…
• 2843 — Colloidal precious metals; inorganic or organic compounds of precious …
• 2844 — Radioactive chemical elements and radioactive isotopes (including the …
• 2845 — Isotopes other than those of heading no. 2844; compounds, inorganic or…
• 2846 — Compounds, inorganic or organic, of rare-earth metals; of yttrium or o…
• 2847 — Hydrogen peroxide; whether or not solidified with urea
• 2849 — Carbides, whether or not chemically defined
• 2850 — Hydrides, nitrides, azides, silicides and borides, whether or not chem…
• 2852 — Inorganic or organic compounds of mercury, excluding amalgams, whether…
• 2853 — Phosphides, chemically defined or not, not ferrophosphorus; other inor…