# HS code 3910.00: Silicones in primary forms

> HS code 3910.00 covers silicones in primary forms. It sits in heading 39.10 (silicones in primary forms) in chapter 39 (plastics and articles thereof). It is the only subheading of heading 39.10, so every good of the heading is classified here.

Source: https://staging.border.bot/hs-codes/391000
Last updated: 13 October 2026

[HS codes](https://staging.border.bot/hs-codes) / [Chapter 39](https://staging.border.bot/hs-codes/39) / [39.10](https://staging.border.bot/hs-codes/3910) / [3910.00](https://staging.border.bot/hs-codes/391000)

## Key facts

- HS code: 3910.00
- Covers: Silicones in primary forms
- Heading: [39.10: Silicones in primary forms](https://staging.border.bot/hs-codes/3910)
- Chapter: [39: Plastics and articles thereof](https://staging.border.bot/hs-codes/39)
- Edition: HS2022
- Duty rates: [Set by each country’s tariff](https://staging.border.bot/countries)

## What this code covers

HS code 3910.00 covers silicones in primary forms.

The legal text of the subheading is “Silicones in primary forms”, in HS2022.

## What it doesn’t cover

It is the only subheading of heading 39.10, so every good of the heading is classified here.

## How it is structured

3910.00 is a six-digit subheading. Its first two digits, 39, are the chapter; the first four, 3910, are heading 39.10; the last two, 00, identify the subheading within the heading.

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

- Chapter 39: Plastics and articles thereof
- Heading 39.10: Silicones in primary forms
- Subheading 3910.00: Silicones in primary forms

## In other countries

No national tariff lines under 3910.00 are live on border.bot yet. Tariffs built on the Harmonized System (HS2022) use 3910.00 at six digits and add their own digits after it.

- Previous subheading: [3909.50](https://staging.border.bot/hs-codes/390950) Polyurethanes
- Next subheading: [3911.10](https://staging.border.bot/hs-codes/391110) Petroleum resins, coumarone, indene or coumarone-indene resins and polyterpenes

## Frequently asked questions

### What does HS code 3910.00 cover?

HS code 3910.00 covers silicones in primary forms.

### Which heading and chapter is HS code 3910.00 in?

HS code 3910.00 is in heading 39.10 (silicones in primary forms) in chapter 39 (plastics and articles thereof).

### Where are goods of heading 39.10 classified when 3910.00 doesn’t fit?

3910.00 is the only subheading of heading 39.10, so every good of the heading is classified there.

## Sources and updates

The Harmonized System legal text comes from border.bot release 1 (edition HS 2022), imported from a file, and has been live since 13 October 2026.

This page was last updated on 13 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://staging.border.bot/hs-codes/391000.json