Diphosphorus pentaoxide; phosphoric acid; polyphosphoric acids, whether or not chemically defined
In plain English
This category includes inorganic chemicals and specific compounds of phosphorus. It covers diphosphorus pentoxide, phosphoric acid, and polyphosphoric acids, with the latter group potentially being chemically defined. The goods are separated into two groups: one for diphosphorus pentoxide and another for phosphoric acid and polyphosphoric acids.
6-digit subheadings (2)
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
Frequent misclassification in this chapter
Pharmaceutical-grade vs. industrial-grade chemistry — same molecule, different chapter (Chapter 30 vs. 28).
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.
Binding tariff ruling databaseOther 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
- 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
- 2833 — Sulphates; alums; peroxosulphates (persulphates)
- 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…