# HS code 2839.90: Silicates; commercial alkali metal silicates

> HS code 2839.90 covers silicates; commercial alkali metal silicates, other than those classified in 2839.11 and 2839.19. It sits in heading 28.39 (silicates; commercial alkali metal silicates) in chapter 28 (inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes). Other goods of heading 28.39 are classified under 2839.11 (of sodium, sodium metasilicates) and 2839.19 (of sodium, other). National tariff lines under 2839.90 are live on border.bot for the United States (2 lines, also used by 1 other country).

Source: https://border.bot/hs-codes/283990
Last updated: 11 October 2026

[HS codes](https://border.bot/hs-codes) / [Chapter 28](https://border.bot/hs-codes/28) / [28.39](https://border.bot/hs-codes/2839) / [2839.90](https://border.bot/hs-codes/283990)

## Key facts

- HS code: 2839.90
- Covers: Silicates; commercial alkali metal silicates
- Heading: [28.39: Silicates; commercial alkali metal silicates](https://border.bot/hs-codes/2839)
- Chapter: [28: Inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes](https://border.bot/hs-codes/28)
- Edition: HS2022
- Duty in the United States: [See its 2 lines](https://border.bot/countries/united-states/hs-codes/283990)

## What this code covers

HS code 2839.90 covers silicates; commercial alkali metal silicates, other than those classified in 2839.11 and 2839.19.

The legal text of the subheading is “Other”, in HS2022.

## What it doesn’t cover

Other goods of heading 28.39 are classified under 2839.11 (of sodium, sodium metasilicates) and 2839.19 (of sodium, other).

- [2839.11](https://border.bot/hs-codes/283911) Of sodium: Sodium metasilicates
- [2839.19](https://border.bot/hs-codes/283919) Of sodium: Other

## How it is structured

2839.90 is a six-digit subheading. Its first two digits, 28, are the chapter; the first four, 2839, are heading 28.39; the last two, 90, identify the subheading within the heading.

Countries add their own digits after these six for their national tariff lines.

- Chapter 28: Inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes
- Heading 28.39: Silicates; commercial alkali metal silicates
- Subheading 2839.90: Other

## In other countries

National tariff lines under 2839.90 are live on border.bot for the United States (2 lines, also used by 1 other country).

- [United States](https://border.bot/countries/united-states/hs-codes/283990): 2 lines, used by 1 other country

- Previous subheading: [2839.19](https://border.bot/hs-codes/283919) Of sodium: Other
- Next subheading: [2840.11](https://border.bot/hs-codes/284011) Disodium tetraborate (refined borax): Anhydrous

## Frequently asked questions

### What does HS code 2839.90 cover?

HS code 2839.90 covers silicates; commercial alkali metal silicates, other than those classified in 2839.11 and 2839.19.

### Which heading and chapter is HS code 2839.90 in?

HS code 2839.90 is in heading 28.39 (silicates; commercial alkali metal silicates) in chapter 28 (inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes).

### Where are goods of heading 28.39 classified when 2839.90 doesn’t fit?

Other goods of heading 28.39 are classified under 2839.11 (of sodium, sodium metasilicates) and 2839.19 (of sodium, other).

### Which countries’ tariffs list national lines under HS code 2839.90?

National tariff lines under 2839.90 are live on border.bot for the United States (2 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/283990.json