# HS code 2521.00: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement

> HS code 2521.00 covers limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement. It sits in heading 25.21 (limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement) in chapter 25 (salt; sulphur; earths and stone; plastering materials, lime and cement). It is the only subheading of heading 25.21, so every good of the heading is classified here. National tariff lines under 2521.00 are live on border.bot for the United States (1 line, also used by 1 other country).

Source: https://border.bot/hs-codes/252100
Last updated: 11 October 2026

[HS codes](https://border.bot/hs-codes) / [Chapter 25](https://border.bot/hs-codes/25) / [25.21](https://border.bot/hs-codes/2521) / [2521.00](https://border.bot/hs-codes/252100)

## Key facts

- HS code: 2521.00
- Covers: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement
- Heading: [25.21: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement](https://border.bot/hs-codes/2521)
- Chapter: [25: Salt; sulphur; earths and stone; plastering materials, lime and cement](https://border.bot/hs-codes/25)
- Edition: HS2022
- Duty in the United States: [See its 1 line](https://border.bot/countries/united-states/hs-codes/252100)

## What this code covers

HS code 2521.00 covers limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement.

The legal text of the subheading is “Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement”, in HS2022.

## What it doesn’t cover

It is the only subheading of heading 25.21, so every good of the heading is classified here.

## How it is structured

2521.00 is a six-digit subheading. Its first two digits, 25, are the chapter; the first four, 2521, are heading 25.21; the last two, 00, identify the subheading within the heading.

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

- Chapter 25: Salt; sulphur; earths and stone; plastering materials, lime and cement
- Heading 25.21: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement
- Subheading 2521.00: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement

## In other countries

National tariff lines under 2521.00 are live on border.bot for the United States (1 line, also used by 1 other country).

- [United States](https://border.bot/countries/united-states/hs-codes/252100): 1 line, used by 1 other country

- Previous subheading: [2520.20](https://border.bot/hs-codes/252020) Plasters
- Next subheading: [2522.10](https://border.bot/hs-codes/252210) Quicklime

## Frequently asked questions

### What does HS code 2521.00 cover?

HS code 2521.00 covers limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement.

### Which heading and chapter is HS code 2521.00 in?

HS code 2521.00 is in heading 25.21 (limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement) in chapter 25 (salt; sulphur; earths and stone; plastering materials, lime and cement).

### Where are goods of heading 25.21 classified when 2521.00 doesn’t fit?

2521.00 is the only subheading of heading 25.21, so every good of the heading is classified there.

### Which countries’ tariffs list national lines under HS code 2521.00?

National tariff lines under 2521.00 are live on border.bot for the United States (1 line, 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/252100.json