# HS heading 28.18: Artificial corundum, whether or not chemically defined; aluminium oxide; aluminium hydroxide

> HS heading 28.18 covers artificial corundum, whether or not chemically defined; aluminium oxide; aluminium hydroxide. It is in chapter 28 (inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes). It is split into 3 subheadings: 2818.10 (artificial corundum, whether or not chemically defined), 2818.20 (aluminium oxide, other than artificial corundum) and 2818.30 (aluminium hydroxide). National tariff lines under heading 28.18 are live on border.bot for the United States (5 lines, also used by 1 other country).

Source: https://border.bot/hs-codes/2818
Last updated: 11 October 2026

[HS codes](https://border.bot/hs-codes) / [Chapter 28](https://border.bot/hs-codes/28) / [28.18](https://border.bot/hs-codes/2818)

## Key facts

- Heading: 28.18
- Description: Artificial corundum, whether or not chemically defined; aluminium oxide; aluminium hydroxide
- Chapter: 28: Inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes
- Subheadings: 3
- Edition: HS2022

## What this code covers

HS heading 28.18 covers artificial corundum, whether or not chemically defined; aluminium oxide; aluminium hydroxide.

It is split into 3 subheadings: 2818.10 (artificial corundum, whether or not chemically defined), 2818.20 (aluminium oxide, other than artificial corundum) and 2818.30 (aluminium hydroxide).

- [2818.10](https://border.bot/hs-codes/281810) Artificial corundum, whether or not chemically defined
- [2818.20](https://border.bot/hs-codes/281820) Aluminium oxide, other than artificial corundum
- [2818.30](https://border.bot/hs-codes/281830) Aluminium hydroxide

## What it doesn’t cover

Other goods of chapter 28 are classified in its other 49 headings, listed below.

- [28.01](https://border.bot/hs-codes/2801) Fluorine, chlorine, bromine and iodine
- [28.02](https://border.bot/hs-codes/2802) Sulphur, sublimed or precipitated; colloidal sulphur
- [28.03](https://border.bot/hs-codes/2803) Carbon (carbon blacks and other forms of carbon not elsewhere specified or included)
- [28.04](https://border.bot/hs-codes/2804) Hydrogen, rare gases and other non-metals
- [28.05](https://border.bot/hs-codes/2805) Alkali or alkaline-earth metals; rare-earth metals, scandium and yttrium, whether or not intermixed or interalloyed; mercury
- [28.06](https://border.bot/hs-codes/2806) Hydrogen chloride (hydrochloric acid); chlorosulphuric acid
- [28.07](https://border.bot/hs-codes/2807) Sulphuric acid; oleum
- [28.08](https://border.bot/hs-codes/2808) Nitric acid; sulphonitric acids
- [28.09](https://border.bot/hs-codes/2809) Diphosphorus pentaoxide; phosphoric acid; polyphosphoric acids, whether or not chemically defined
- [28.10](https://border.bot/hs-codes/2810) Oxides of boron; boric acids
- [28.11](https://border.bot/hs-codes/2811) Other inorganic acids and other inorganic oxygen compounds of non-metals
- [28.12](https://border.bot/hs-codes/2812) Halides and halide oxides of non-metals
- [28.13](https://border.bot/hs-codes/2813) Sulphides of non-metals; commercial phosphorus trisulphide
- [28.14](https://border.bot/hs-codes/2814) Ammonia, anhydrous or in aqueous solution
- [28.15](https://border.bot/hs-codes/2815) Sodium hydroxide (caustic soda); potassium hydroxide (caustic potash); peroxides of sodium or potassium
- [28.16](https://border.bot/hs-codes/2816) Hydroxide and peroxide of magnesium; oxides, hydroxides and peroxides, of strontium or barium
- [28.17](https://border.bot/hs-codes/2817) Zinc oxide; zinc peroxide
- [28.19](https://border.bot/hs-codes/2819) Chromium oxides and hydroxides
- [28.20](https://border.bot/hs-codes/2820) Manganese oxides
- [28.21](https://border.bot/hs-codes/2821) Iron oxides and hydroxides; earth colours containing 70 % or more by weight of combined iron evaluated as Fe2O3
- [28.22](https://border.bot/hs-codes/2822) Cobalt oxides and hydroxides; commercial cobalt oxides
- [28.23](https://border.bot/hs-codes/2823) Titanium oxides
- [28.24](https://border.bot/hs-codes/2824) Lead oxides; red lead and orange lead
- [28.25](https://border.bot/hs-codes/2825) Hydrazine and hydroxylamine and their inorganic salts; other inorganic bases; other metal oxides, hydroxides and peroxides
- [28.26](https://border.bot/hs-codes/2826) Fluorides; fluorosilicates, fluoroaluminates and other complex fluorine salts
- [28.27](https://border.bot/hs-codes/2827) Chlorides, chloride oxides and chloride hydroxides; bromides and bromide oxides; iodides and iodide oxides
- [28.28](https://border.bot/hs-codes/2828) Hypochlorites; commercial calcium hypochlorite; chlorites; hypobromites
- [28.29](https://border.bot/hs-codes/2829) Chlorates and perchlorates; bromates and perbromates; iodates and periodates
- [28.30](https://border.bot/hs-codes/2830) Sulphides; polysulphides, whether or not chemically defined
- [28.31](https://border.bot/hs-codes/2831) Dithionites and sulphoxylates
- [28.32](https://border.bot/hs-codes/2832) Sulphites; thiosulphates
- [28.33](https://border.bot/hs-codes/2833) Sulphates; alums; peroxosulphates (persulphates)
- [28.34](https://border.bot/hs-codes/2834) Nitrites; nitrates
- [28.35](https://border.bot/hs-codes/2835) Phosphinates (hypophosphites), phosphonates (phosphites) and phosphates; polyphosphates, whether or not chemically defined
- [28.36](https://border.bot/hs-codes/2836) Carbonates; peroxocarbonates (percarbonates); commercial ammonium carbonate containing ammonium carbamate
- [28.37](https://border.bot/hs-codes/2837) Cyanides, cyanide oxides and complex cyanides
- [28.39](https://border.bot/hs-codes/2839) Silicates; commercial alkali metal silicates
- [28.40](https://border.bot/hs-codes/2840) Borates; peroxoborates (perborates)
- [28.41](https://border.bot/hs-codes/2841) Salts of oxometallic or peroxometallic acids
- [28.42](https://border.bot/hs-codes/2842) Other salts of inorganic acids or peroxoacids (including aluminosilicates whether or not chemically defined), other than azides
- [28.43](https://border.bot/hs-codes/2843) Colloidal precious metals; inorganic or organic compounds of precious metals, whether or not chemically defined; amalgams of precious metals
- [28.44](https://border.bot/hs-codes/2844) Radioactive chemical elements and radioactive isotopes (including the fissile or fertile chemical elements and isotopes) and their compounds; mixtures and residues containing these products
- [28.45](https://border.bot/hs-codes/2845) Isotopes other than those of heading 28.44; compounds, inorganic or organic, of such isotopes, whether or not chemically defined
- [28.46](https://border.bot/hs-codes/2846) Compounds, inorganic or organic, of rare-earth metals, of yttrium or of scandium or of mixtures of these metals
- [28.47](https://border.bot/hs-codes/2847) Hydrogen peroxide, whether or not solidified with urea
- [28.49](https://border.bot/hs-codes/2849) Carbides, whether or not chemically defined
- [28.50](https://border.bot/hs-codes/2850) Hydrides, nitrides, azides, silicides and borides, whether or not chemically defined, other than compounds which are also carbides of heading 28.49
- [28.52](https://border.bot/hs-codes/2852) Inorganic or organic compounds of mercury, whether or not chemically defined, excluding amalgams
- [28.53](https://border.bot/hs-codes/2853) Phosphides, whether or not chemically defined, excluding ferrophosphorus; other inorganic compounds (including distilled or conductivity water and water of similar purity); liquid air (whether or not rare gases have been removed); compressed air; amalgams, other than amalgams of precious metals

## How it is structured

Heading 28.18 is one of 50 headings in chapter 28. Its first two digits, 28, are the chapter; the next two, 18, number the heading within it. Its subheadings add two more digits (2818.10, 2818.20, 2818.30).

## In other countries

National tariff lines under heading 28.18 are live on border.bot for the United States (5 lines, also used by 1 other country).

- [United States](https://border.bot/countries/united-states/hs-codes/28): 5 lines, used by 1 other country

- Previous heading: [28.17](https://border.bot/hs-codes/2817) Zinc oxide; zinc peroxide
- Next heading: [28.19](https://border.bot/hs-codes/2819) Chromium oxides and hydroxides

## Frequently asked questions

### What does HS heading 28.18 cover?

HS heading 28.18 covers artificial corundum, whether or not chemically defined; aluminium oxide; aluminium hydroxide.

### Which chapter is HS heading 28.18 in?

HS heading 28.18 is in chapter 28 (inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes).

### How many subheadings does HS heading 28.18 have?

HS heading 28.18 has 3 subheadings: 2818.10 (artificial corundum, whether or not chemically defined), 2818.20 (aluminium oxide, other than artificial corundum) and 2818.30 (aluminium hydroxide).

### Which countries’ tariffs list national lines under HS heading 28.18?

National tariff lines under heading 28.18 are live on border.bot for the United States (5 lines, also used by 1 other country).

## Sources and updates

The Harmonized System legal text comes from border.bot release 2 (edition HS 2022), imported from a file, and has been live since 11 October 2026.

This page was last updated on 11 October 2026.

Guidance from published tariff data, not a binding ruling. For a decision customs must follow, apply to the destination’s customs authority for a binding tariff ruling.

Machine-readable: https://border.bot/hs-codes/2818.json