2621.90.00.00—Other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste, otherGeneral
Free
Units
t
Column 2
Free
Special
—
Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 2621.90.00.00 is the U.S. Harmonized Tariff Schedule classification for Other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste, other. It's a 10-digit statistical line in Chapter 26: Ores, slag and ash, 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 →
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.
The tariff classification of rice hull (husk) ash from India
The tariff classification of cenospheres from Germany
The tariff classification of cenospheres from China and India
Revocation of Headquarters Ruling Letter (HQ) 955742, dated April 7, 1994; Classification of micro silica sand.
The tariff classification of granulated copper slag from India
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 2621.90.00.00 is the U.S. Harmonized Tariff Schedule classification for Other slag and ash, including seaweed ash (kelp); ash and residues from the incineration of municipal waste, other. It belongs to Chapter 26 of the HTSUS.
The general (Column 1) duty rate for HTS 2621.90.00.00 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 2621.90.00.00 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 2621.90.00.00 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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