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HS Heading 2521 : Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement

HEADING DEFINITION & DISAMBIGUATION

HS Heading 2521 encompasses limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement. It classifies 1 6-digit WCO subheadings within Chapter 25 under the Harmonized System [USITC HTS 2026].

Chapter

Ch 25

Heading

2521

Subheadings

1 HS6

Status

Verified 2026

Subheadings Under Heading 2521

HS Code	WCO 6-Digit Subheading Description	Chapter	Operational Package
2521.00	Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement	25	View 2521.00 Package →

DISAMBIGUATION & CLASSIFICATION GUIDE

How to Select the Correct Subheading Under Heading 2521

Commercial shipments must be declared under the exact 6-digit WCO subheading that matches physical, chemical, or processing characteristics. Review the subheading descriptions above and verify against binding CBP CROSS rulings prior to entry filing.

Official Primary Sources & Authority References

USITC HTS Heading 2521 ↗

United States International Trade Commission official Harmonized Tariff Schedule.

CBP CROSS Rulings ↗

CBP e-Rulings database for Heading 2521 precedent rulings.

WCO Nomenclature ↗

World Customs Organization Harmonized System 2022 nomenclature standard.

U.S. Census Foreign Trade ↗

U.S. Census Bureau HTS-to-NAICS concordance and Schedule B export database.

Heading 2521 Frequently Asked Questions (FAQ)

What commercial articles are grouped under HS Heading 2521?

HS Heading 2521 covers Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement, grouping 1 6-digit WCO subheadings.

How are 6-digit subheadings structured under Heading 2521?

Subheadings under Heading 2521 range from 2521.11 to 2521.90, classifying goods by processing state, origin, or material composition.

What is the representative US import duty rate for Heading 2521?

US MFN general duty rates for Heading 2521 commodities range from Duty-Free up to representative ad valorem percentages under the 2026 US HTS.

Are Section 301 tariffs applicable to goods under Heading 2521?

Section 301 additional tariffs depend on the specific 8-digit or 10-digit US HTS code and country of origin (e.g. China Lists 1–4A).

What PGA message set flags apply to Heading 2521?

Partner Government Agency flags (FDA, USDA APHIS, EPA) apply depending on the specific commodity sub-classification.

How do I distinguish between subheadings under Heading 2521?

Review WCO subheading terms and candidate descriptions. For example, unroasted vs. roasted or decaffeinated vs. non-decaffeinated.

Can goods under Heading 2521 enter duty-free under USMCA?

Yes. Goods originating in USMCA territories (US, Mexico, Canada) enter duty-free under SPI code P with a valid Certificate of Origin.

What is the Section 321 de minimis limit for Heading 2521?

Eligible import shipments valued at $800 USD or less imported by one person on one day enter duty-free under 19 U.S.C. 1321.

What documents are required for formal customs entry of Heading 2521?

Commercial Invoice, Packing List, Bill of Lading, and CBP Form 7501 are mandatory for entries exceeding $2,500 USD.

How can an importer get a binding CBP classification ruling for Heading 2521?

Importers may apply for a binding ruling via CBP National Commodity Specialist Division under 19 CFR Part 177.