Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 2809.10.00.00 is the U.S. Harmonized Tariff Schedule classification for Diphosphorus pentaoxide. It's a 10-digit statistical line in Chapter 28: Inorganic chemicals; organic or inorganic compounds of precious metals, of rare-earth metals, of radioactive elements or of isotopes, Section VI: Products of the Chemical or Allied Industries, 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 →
Past CBP decisions classifying real products under this HTS code. Useful precedent when classifying a similar product — each ruling shows how CBP interpreted the code for a specific case.
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 2809.10.00.00 is the U.S. Harmonized Tariff Schedule classification for Diphosphorus pentaoxide. It belongs to Chapter 28 of the HTSUS.
The general (Column 1) duty rate for HTS 2809.10.00.00 is Free. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
The Column 2 rate for HTS 2809.10.00.00 is 25%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
No active Chapter 99 tariff overlays (Section 301, Section 232, IEEPA reciprocal, etc.) currently flag HTS 2809.10.00.00 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 2809.10.00.00 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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