2528.00.00.10—Natural calcium boratesGeneral
Free
Units
kg
Column 2
Free
Special
—
Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 2528.00.00.10 is the U.S. Harmonized Tariff Schedule classification for Natural calcium borates. It's a 10-digit statistical line in Chapter 25: Salt; sulfur; earths and stone; plastering materials, lime and cement, Section V: Mineral Products, used by U.S. Customs and Border Protection to determine the duty rate at entry. No Chapter 99 tariff modifications (Section 301, Section 232, IEEPA) or AD/CVD orders currently flag this code in Tandom's catalog.
New to HTS codes? Read our guide on how HTS classification works →
HTS 2528.00.00.10 is the U.S. Harmonized Tariff Schedule classification for Natural calcium borates. It belongs to Chapter 25 of the HTSUS.
The general (Column 1) duty rate for HTS 2528.00.00.10 is Free. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
No active Chapter 99 tariff overlays (Section 301, Section 232, IEEPA reciprocal, etc.) currently flag HTS 2528.00.00.10 in Tandom's catalog. Use the calculator's date + origin inputs to confirm against any retroactive overlay you may be filing.
No active AD/CVD orders currently flag HTS 2528.00.00.10 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
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