Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 2931.90.90.10 is the U.S. Harmonized Tariff Schedule classification for Other organo-inorganic compounds, organo-silicon compounds. It's a 10-digit statistical line in Chapter 29: Organic chemicals, Section VI: Products of the Chemical or Allied Industries, used by U.S. Customs and Border Protection to determine the duty rate at entry. 2 Chapter 99 tariff modifications currently stack on top of the base rate.
New to HTS codes? Read our guide on how HTS classification works →
Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.88.04 | section_301 | The duty provided in the applicable subheading + 25% |
| 9903.88.16 | section_301 | The duty provided in the applicable subheading + 15% |
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 Trimethylsilane (CAS # 993-07-7) and Tetramethylsilane (CAS # 75-76-3) from China
The tariff classification of Hydrolyzed or Polymerized Alkoxysilanes or Organosilanes from Germany, China or Japan
The tariff classification of SF1173 (D4) and SF1202 (D5) from China
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 2931.90.90.10 is the U.S. Harmonized Tariff Schedule classification for Other organo-inorganic compounds, organo-silicon compounds. It belongs to Chapter 29 of the HTSUS.
The general (Column 1) duty rate for HTS 2931.90.90.10 is 3.7% . This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 2931.90.90.10 from countries party to a trade program (such as USMCA, KORUS, GSP, or the African Growth and Opportunity Act) may qualify for the special rate: Free (A*,AU,BH,CL,CO,D,E,IL,JO,K,KR,MA,OM,P,PA,PE,S,SG). Eligibility depends on rules of origin and certification.
The Column 2 rate for HTS 2931.90.90.10 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).
Yes — HTS 2931.90.90.10 is covered by section_301 provision 9903.88.04 (The duty provided in the applicable subheading + 25%). 1 additional overlay also touch this code. Open the code page for the full overlay stack with effective dates and country scopes.
No active AD/CVD orders currently flag HTS 2931.90.90.10 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
Free Trade Agreement and special-program eligibility
Tandom guides relevant to this code
How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
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