# HS heading 26.21: Other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste

> HS heading 26.21 covers other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste. It is in chapter 26 (ores, slag and ash). It is split into 2 subheadings: 2621.10 (ash and residues from the incineration of municipal waste) and 2621.90 (other). National tariff lines under heading 26.21 are live on border.bot for the United States (2 lines, also used by 1 other country).

Source: https://border.bot/hs-codes/2621
Last updated: 11 October 2026

[HS codes](https://border.bot/hs-codes) / [Chapter 26](https://border.bot/hs-codes/26) / [26.21](https://border.bot/hs-codes/2621)

## Key facts

- Heading: 26.21
- Description: Other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste
- Chapter: 26: Ores, slag and ash
- Subheadings: 2
- Edition: HS2022

## What this code covers

HS heading 26.21 covers other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste.

It is split into 2 subheadings: 2621.10 (ash and residues from the incineration of municipal waste) and 2621.90 (other).

- [2621.10](https://border.bot/hs-codes/262110) Ash and residues from the incineration of municipal waste
- [2621.90](https://border.bot/hs-codes/262190) Other

## What it doesn’t cover

Other goods of chapter 26 are classified in its other 20 headings, listed below.

- [26.01](https://border.bot/hs-codes/2601) Iron ores and concentrates, including roasted iron pyrites
- [26.02](https://border.bot/hs-codes/2602) Manganese ores and concentrates, including ferruginous manganese ores and concentrates with a manganese content of 20 % or more, calculated on the dry weight
- [26.03](https://border.bot/hs-codes/2603) Copper ores and concentrates
- [26.04](https://border.bot/hs-codes/2604) Nickel ores and concentrates
- [26.05](https://border.bot/hs-codes/2605) Cobalt ores and concentrates
- [26.06](https://border.bot/hs-codes/2606) Aluminium ores and concentrates
- [26.07](https://border.bot/hs-codes/2607) Lead ores and concentrates
- [26.08](https://border.bot/hs-codes/2608) Zinc ores and concentrates
- [26.09](https://border.bot/hs-codes/2609) Tin ores and concentrates
- [26.10](https://border.bot/hs-codes/2610) Chromium ores and concentrates
- [26.11](https://border.bot/hs-codes/2611) Tungsten ores and concentrates
- [26.12](https://border.bot/hs-codes/2612) Uranium or thorium ores and concentrates
- [26.13](https://border.bot/hs-codes/2613) Molybdenum ores and concentrates
- [26.14](https://border.bot/hs-codes/2614) Titanium ores and concentrates
- [26.15](https://border.bot/hs-codes/2615) Niobium, tantalum, vanadium or zirconium ores and concentrates
- [26.16](https://border.bot/hs-codes/2616) Precious metal ores and concentrates
- [26.17](https://border.bot/hs-codes/2617) Other ores and concentrates
- [26.18](https://border.bot/hs-codes/2618) Granulated slag (slag sand) from the manufacture of iron or steel
- [26.19](https://border.bot/hs-codes/2619) Slag, dross (other than granulated slag), scalings and other waste from the manufacture of iron or steel
- [26.20](https://border.bot/hs-codes/2620) Slag, ash and residues (other than from the manufacture of iron or steel) containing metals, arsenic or their compounds

## How it is structured

Heading 26.21 is one of 21 headings in chapter 26. Its first two digits, 26, are the chapter; the next two, 21, number the heading within it. Its subheadings add two more digits (2621.10, 2621.90).

## In other countries

National tariff lines under heading 26.21 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/26): 2 lines, used by 1 other country

- Previous heading: [26.20](https://border.bot/hs-codes/2620) Slag, ash and residues (other than from the manufacture of iron or steel) containing metals, arsenic or their compounds
- Next heading: [27.01](https://border.bot/hs-codes/2701) Coal; briquettes, ovoids and similar solid fuels manufactured from coal

## Frequently asked questions

### What does HS heading 26.21 cover?

HS heading 26.21 covers other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste.

### Which chapter is HS heading 26.21 in?

HS heading 26.21 is in chapter 26 (ores, slag and ash).

### How many subheadings does HS heading 26.21 have?

HS heading 26.21 has 2 subheadings: 2621.10 (ash and residues from the incineration of municipal waste) and 2621.90 (other).

### Which countries’ tariffs list national lines under HS heading 26.21?

National tariff lines under heading 26.21 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/2621.json