HS 281000 Diboron trioxide
Quick Answer: HS code 281000 covers Diboron trioxide, also known as boric oxide or boron trioxide. This inorganic chemical compound is primarily used in the manufacture of borosilicate glass, ceramics, enamels, and as a fluxing agent in metallurgy. For importers and exporters, understanding the varying duty rates is crucial. The UK Trade Tariff generally applies a 0.00% ad valorem duty rate. The EU TARIC system shows rates ranging from 0.00% to 3.70% ad valorem, depending on the specific product and origin. In the United States, the general Most Favored Nation (MFN) duty rate is 8.5% ad valorem, though many countries benefit from preferential duty rates, such as 1.5% or Free under various Free Trade Agreements (e.g., A, AU, BH, CL, CO, D, E, IL, JO, KR, MA, OM, P, PA, PE, S, SG). Importers should verify specific origin-based preferences to optimize landed costs.
What Are the Import Duty Rates?
🇬🇧 United Kingdom
| Code | MFN | Preferential | Unit |
|---|---|---|---|
| 2810001000 | 0.00 % | — | — |
| 2810009000 | 0.00 % | — | — |
🇪🇺 European Union (TARIC)
| Code | MFN | Preferential | Unit |
|---|---|---|---|
| 2810001000 | 0.00 % | — | — |
| 2810009000 | 3.70 % | — | — |
🇺🇸 United States (HTSUS)
| Code | MFN | Preferential | Unit |
|---|---|---|---|
| 2810000000 | 1.5% | Free (17 programs) | ["t"] |
Special rates available under trade agreements including USMCA, KORUS, GSP.
Duty rates sourced from the USITC (US International Trade Commission) Harmonized Tariff Schedule (HTS) (accessed 2/22/2026), EU TARIC – DG TAXUD (Directorate-General for Taxation and Customs Union) (accessed 2/22/2026), and UK Trade Tariff – HMRC (His Majesty's Revenue and Customs) (accessed 2/22/2026).
Data compiled and presented by HSRates.
Which Trade Agreements Reduce Duties for HS 2810.00?
Imports of Diboron trioxide may qualify for reduced or zero duty rates under free trade agreements and preferential programs. The overview below shows available preferential arrangements by jurisdiction, compiled by HSRates from official tariff and trade agreement data.
United States (HTSUS)
Free for USMCA, KORUS, GSP, and 14 other programs
European Union (TARIC)
Preferential rate data not yet available.
United Kingdom
Preferential rate data not yet available.
Preferential rates require proof of origin and may be subject to quotas or conditions. Always verify eligibility with a licensed customs broker.
Data compiled by HSRates.
Which Preferential Rates Apply to Your Origin Country?
Select an origin country to see if preferential rates apply.
Preferential rates based on available trade agreements. Actual rates may vary.
How Has Trade Volume Developed?
How to Classify This HS Code?
What products does HS 281000 cover?
This subheading covers diboron trioxide, also known as boric anhydride or boron oxide, which is a chemical compound with the formula B2O3. It is a white, glassy solid that is hygroscopic and typically used as a fluxing agent in glass and ceramics manufacturing, as well as in the production of other boron compounds. The WCO Harmonized System Explanatory Notes for Chapter 28, Heading 2810, specifically identify boron oxides, including diboron trioxide, as falling within this classification. Official definitions from the USITC Harmonized Tariff Schedule (HTS) and the EU TARIC system consistently align with this scope, encompassing the pure chemical compound.
What falls outside HS 281000?
The following products are excluded from HS 281000: natural borates and concentrates thereof, which are classified under Heading 2528. For instance, crude natural borax (sodium tetraborate decahydrate) is classified under 2528.00.00. Additionally, prepared glazes, enamels, or other ceramic preparations containing diboron trioxide as an ingredient, but not being the pure compound itself, would be classified elsewhere, typically in Chapter 32. Boron carbide, a different boron compound used as an abrasive, is classified under Heading 2849.00.10, as it is a carbide, not an oxide of boron.
What are common classification mistakes for HS 281000?
A common error is misclassifying natural borate minerals or their concentrates under 281000, instead of their correct classification under Heading 2528. Importers sometimes confuse the pure chemical compound diboron trioxide with naturally occurring boron-containing ores. Another mistake involves classifying mixtures or preparations where diboron trioxide is merely an ingredient, rather than the primary substance, under this heading. According to General Interpretative Rule (GRI) 1, classification is determined by the terms of the headings and any relative section or chapter notes. GRI 3(b) would apply if it were a mixture, but for pure diboron trioxide, GRI 1 is paramount, requiring it to be the distinct chemical compound.
How should importers classify products under HS 281000?
The correct procedure for classifying products under HS 281000 involves verifying that the product is indeed pure diboron trioxide (boron oxide, B2O3) and not a natural ore, concentrate, or a prepared mixture. Importers and customs brokers should obtain a Certificate of Analysis (CoA) or a Safety Data Sheet (SDS) from the manufacturer, which clearly states the chemical name, CAS number (typically 1303-86-2 for diboron trioxide), and chemical formula. This documentation provides definitive proof of the product's identity and purity. Cross-referencing with the WCO Explanatory Notes for Chapter 28, Heading 2810, will confirm that "boron oxides" are specifically included, ensuring accurate classification under this 8-digit or 10-digit subheading.
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FAQ
What is the Most Favored Nation (MFN) import duty rate for HS code 281000 (Diboron trioxide) in key markets?
The MFN duty rates for HS code 281000 (Diboron trioxide) vary by importing country. For example, the United States generally applies a 'Free' (0.00% ad valorem) MFN duty rate. The European Union's TARIC database also indicates a 0.00% ad valorem MFN duty rate. The UK Global Tariff similarly lists a 0.00% ad valorem MFN duty rate. However, other countries may apply different rates, such as 3.70% or 8.5% ad valorem. Importers should always consult the official tariff schedule of the specific importing country (e.g., USITC Harmonized Tariff Schedule, EU TARIC, UK Trade Tariff) for the most current and accurate information.
Are there any preferential duty rates available for Diboron trioxide (HS 281000) under free trade agreements?
Yes, preferential duty rates, often 'Free' (0.00% ad valorem), are commonly available for Diboron trioxide (HS 281000) when imported under various Free Trade Agreements (FTAs) or Generalized System of Preferences (GSP) programs. For instance, the United States offers preferential 'Free' rates for imports from countries eligible under agreements such as A (Generalized System of Preferences), AU (Australia FTA), BH (Bahrain FTA), CL (Chile FTA), CO (Colombia TPA), D (Andean Trade Preference Act), E (African Growth and Opportunity Act), IL (Israel FTA), JO (Jordan FTA), KR (Korea FTA), MA (Morocco FTA), OM (Oman FTA), P (Panama TPA), PA (Peru TPA), PE (Peru TPA), S (Singapore FTA), and SG (Singapore FTA). Importers must ensure compliance with the specific Rules of Origin for the relevant agreement and provide proper documentation, such as a Certificate of Origin, to claim preferential treatment.
What are the key classification criteria for Diboron trioxide under HS code 281000?
HS code 281000 specifically covers 'Oxides of boron; boric acids.' Diboron trioxide (B2O3) falls squarely within this heading as it is an oxide of boron. The classification is generally straightforward for chemically pure diboron trioxide. Key criteria for classification under this heading include the chemical composition (presence of boron and oxygen), its identity as an oxide, and its form (e.g., powder, flakes, glassy solid). Importers should ensure that the product's chemical name and CAS number (e.g., CAS 1303-86-2 for Diboron trioxide) align with the description for HS 281000. If the product is a mixture or preparation containing diboron trioxide, its classification might fall under a different heading based on the predominant component or essential character, as per the General Rules of Interpretation (GRIs).
What documentation is typically required for importing Diboron trioxide (HS 281000)?
Standard import documentation for Diboron trioxide (HS 281000) includes a commercial invoice, packing list, bill of lading or air waybill, and a customs declaration form. To claim preferential duty rates under a free trade agreement, a valid Certificate of Origin (e.g., a Free Trade Agreement Certificate of Origin or GSP Form A) issued by the exporter or producer is essential. Depending on the importing country and the specific end-use, additional documentation such as a Material Safety Data Sheet (MSDS) may be requested for chemical products to ensure compliance with environmental, health, and safety regulations. Importers should verify specific country-level requirements with their customs broker or the relevant customs authority prior to shipment.