# HS code 3815.90: Reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included

> HS code 3815.90 covers reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included, other than those classified in 3815.11, 3815.12 and 3815.19. It sits in heading 38.15 (reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included) in chapter 38 (miscellaneous chemical products). Other goods of heading 38.15 are classified under 3815.11 (supported catalysts, with nickel or nickel compounds as the active substance), 3815.12 (supported catalysts, with precious metal or precious metal compounds as the active substance) and 3815.19 (supported catalysts, other). National tariff lines under 3815.90 are live on border.bot for the United States (4 lines, also used by 1 other country).

Source: https://border.bot/hs-codes/381590
Last updated: 11 October 2026

[HS codes](https://border.bot/hs-codes) / [Chapter 38](https://border.bot/hs-codes/38) / [38.15](https://border.bot/hs-codes/3815) / [3815.90](https://border.bot/hs-codes/381590)

## Key facts

- HS code: 3815.90
- Covers: Reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included
- Heading: [38.15: Reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included](https://border.bot/hs-codes/3815)
- Chapter: [38: Miscellaneous chemical products](https://border.bot/hs-codes/38)
- Edition: HS2022
- Duty in the United States: [See its 4 lines](https://border.bot/countries/united-states/hs-codes/381590)

## What this code covers

HS code 3815.90 covers reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included, other than those classified in 3815.11, 3815.12 and 3815.19.

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

## What it doesn’t cover

Other goods of heading 38.15 are classified under 3815.11 (supported catalysts, with nickel or nickel compounds as the active substance), 3815.12 (supported catalysts, with precious metal or precious metal compounds as the active substance) and 3815.19 (supported catalysts, other).

- [3815.11](https://border.bot/hs-codes/381511) Supported catalysts: With nickel or nickel compounds as the active substance
- [3815.12](https://border.bot/hs-codes/381512) Supported catalysts: With precious metal or precious metal compounds as the active substance
- [3815.19](https://border.bot/hs-codes/381519) Supported catalysts: Other

## How it is structured

3815.90 is a six-digit subheading. Its first two digits, 38, are the chapter; the first four, 3815, are heading 38.15; the last two, 90, identify the subheading within the heading.

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

- Chapter 38: Miscellaneous chemical products
- Heading 38.15: Reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included
- Subheading 3815.90: Other

## In other countries

National tariff lines under 3815.90 are live on border.bot for the United States (4 lines, also used by 1 other country).

- [United States](https://border.bot/countries/united-states/hs-codes/381590): 4 lines, used by 1 other country

- Previous subheading: [3815.19](https://border.bot/hs-codes/381519) Supported catalysts: Other
- Next subheading: [3816.00](https://border.bot/hs-codes/381600) Refractory cements, mortars, concretes and similar compositions, including dolomite ramming mix, other than products of heading 38.01

## Frequently asked questions

### What does HS code 3815.90 cover?

HS code 3815.90 covers reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included, other than those classified in 3815.11, 3815.12 and 3815.19.

### Which heading and chapter is HS code 3815.90 in?

HS code 3815.90 is in heading 38.15 (reaction initiators, reaction accelerators and catalytic preparations, not elsewhere specified or included) in chapter 38 (miscellaneous chemical products).

### Where are goods of heading 38.15 classified when 3815.90 doesn’t fit?

Other goods of heading 38.15 are classified under 3815.11 (supported catalysts, with nickel or nickel compounds as the active substance), 3815.12 (supported catalysts, with precious metal or precious metal compounds as the active substance) and 3815.19 (supported catalysts, other).

### Which countries’ tariffs list national lines under HS code 3815.90?

National tariff lines under 3815.90 are live on border.bot for the United States (4 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/381590.json