HS 293145 Salt of methylphosphonic acid and (aminoiminomethyl)urea (1: 1)
Quick Answer: HS code 293145 specifically covers the chemical compound known as "Salt of methylphosphonic acid and (aminoiminomethyl)urea (1:1)". This refers to a particular salt formed from methylphosphonic acid and guanidine (aminoiminomethyl)urea, often used as a flame retardant or in chemical synthesis. Importers and exporters should note the varying duty rates: the UK applies a 6.00% ad valorem duty, while the EU's TARIC system lists 6.50%. For the US, the general most-favored-nation (MFN) rate is 3.7% ad valorem, but significant preferential duty-free treatment is available under various free trade agreements (e.g., A, AU, CL, KR, SG). Conversely, a 25% duty may apply under specific trade remedy measures. Accurate classification is crucial to leverage preferential tariffs and avoid penalties.
What Are the Import Duty Rates?
🇬🇧 United Kingdom
| Code | MFN | Preferential | Unit |
|---|---|---|---|
| 2931450000 | 6.00 % | — | — |
🇪🇺 European Union (TARIC)
| Code | MFN | Preferential | Unit |
|---|---|---|---|
| 2931450000 | 6.50 % | — | — |
🇺🇸 United States (HTSUS)
| Code | MFN | Preferential | Unit |
|---|---|---|---|
| 2931450000 | 3.7% | Free (18 programs) | ["kg"] |
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 2931.45?
Imports of Salt of methylphosphonic acid and (aminoiminomethyl)urea (1: 1) 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 15 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?
Trade Volume 2023
How to Classify This HS Code?
What products does HS 293145 cover?
This subheading covers a very specific chemical compound: the salt of methylphosphonic acid and (aminoiminomethyl)urea, in a 1:1 molar ratio. This precise description is derived directly from the Harmonized System Nomenclature, as published by the World Customs Organization (WCO), and is consistently reflected in national tariffs such as the USITC Harmonized Tariff Schedule of the United States (HTSUS) and the EU TARIC. This compound is a distinct organo-phosphorus derivative, specifically a phosphonate, and its chemical structure is critical for accurate classification. It is not a mixture but a defined chemical salt with a precise stoichiometric relationship between its components, distinguishing it from simple physical blends.
What falls outside HS 293145?
The following products are excluded from HS 293145: methylphosphonic acid itself (classified under other subheadings within 2931, depending on its specific form), or (aminoiminomethyl)urea (guanidine, which falls under Chapter 29, typically in 2925). Furthermore, mixtures containing this salt but not solely consisting of it, or salts where the molar ratio is not precisely 1:1, would generally be excluded and classified elsewhere, potentially under other subheadings of 2931 if they are other organo-phosphorus compounds, or even under Chapter 38 if they are preparations. Other organo-phosphorus compounds not specifically named here, even if structurally similar, would also be excluded.
What are common classification mistakes for HS 293145?
A common error is misclassifying this specific salt as a generic organo-phosphorus compound under a more general subheading within 2931, or even as a mixture under Chapter 38, if its precise chemical identity and stoichiometric ratio are not fully recognized. Importers might incorrectly assume that any salt of methylphosphonic acid belongs here, overlooking the crucial "and (aminoiminomethyl)urea (1:1)" specificity. This often stems from a failure to apply General Interpretative Rule (GRI) 1, which dictates that classification is determined according to the terms of the headings and any relative section or chapter notes, and GRI 6, which extends this principle to subheadings. Precise chemical analysis and understanding of the compound's exact structure are paramount to avoid such errors.
How should importers classify products under HS 293145?
The correct procedure for classifying products under HS 293145 involves a rigorous chemical identification process. Importers and customs brokers must ensure that the product is unequivocally the salt of methylphosphonic acid and (aminoiminomethyl)urea, specifically in a 1:1 molar ratio. This requires obtaining and reviewing the product's Certificate of Analysis (CoA), Safety Data Sheet (SDS), and any other relevant technical specifications that confirm its exact chemical name, CAS number, and stoichiometric composition. If there is any doubt regarding the 1:1 ratio or the precise chemical identity, further laboratory analysis may be necessary. Consulting the WCO Explanatory Notes for Heading 2931 and seeking a binding tariff information (BTI) ruling from the relevant customs authority (e.g., US Customs and Border Protection or an EU member state's customs) is highly recommended for certainty.
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FAQ
What is the Most Favored Nation (MFN) import duty rate for HS code 2931.45 in key markets, and are there any significant variations?
The MFN import duty rate for HS 2931.45, 'Salt of methylphosphonic acid and (aminoiminomethyl)urea (1: 1)', varies by importing country. For instance, the United States applies an MFN (General) duty rate of 6.5% ad valorem. The European Union's TARIC database indicates a Common Customs Tariff (CCT) duty rate of 6.00% ad valorem. The United Kingdom Global Tariff (UKGT) also lists a 6.0% ad valorem duty rate. Importers should always verify the current MFN rate with the specific country's customs authority or official tariff database, as rates can be subject to change.
Which preferential trade agreements offer duty-free entry for HS 2931.45, and what are the typical requirements to claim these benefits?
Many preferential trade agreements offer duty-free entry for HS 2931.45, provided the goods meet the respective rules of origin. For example, the United States grants duty-free treatment under various agreements, including but not limited to those with Australia (AU), Bahrain (BH), Chile (CL), Colombia (CO), Israel (IL), Jordan (JO), Korea (KR), Morocco (MA), Oman (OM), Panama (PA), Peru (PE), and Singapore (SG). The specific indicator 'Free (A,AU,BH,CL,CO,D,E,IL,JO,K,KR,MA,OM,P,PA,PE,S,SG)' suggests eligibility under numerous U.S. Free Trade Agreements (FTAs) and potentially the Generalized System of Preferences (GSP) for eligible developing countries. To claim preferential duty rates, importers must typically provide a valid Certificate of Origin or an origin declaration, demonstrating that the product satisfies the origin criteria stipulated in the relevant trade agreement. Customs brokers require this documentation to correctly declare the goods.
What are the key classification criteria for HS 2931.45, and what distinguishes it from other organo-phosphorus compounds?
HS 2931.45 specifically covers 'Salt of methylphosphonic acid and (aminoiminomethyl)urea (1: 1)'. The primary classification criteria hinge on the precise chemical identity and structure of this compound. It falls under Chapter 29, 'Organic chemicals', and more specifically, under heading 2931, 'Other organo-inorganic compounds'. The '1:1' ratio indicates a specific stoichiometric relationship between the methylphosphonic acid and (aminoiminomethyl)urea components in the salt. Distinguishing it from other organo-phosphorus compounds (e.g., those under 2931.90) requires laboratory analysis or a clear Certificate of Analysis from the manufacturer confirming the exact chemical name, CAS number, and molecular structure, ensuring it precisely matches the description for 2931.45 and not a different derivative or compound.
Are there any specific documentation requirements, beyond standard customs declarations, for importing HS 2931.45, especially concerning chemical safety or end-use declarations?
Beyond standard commercial invoices, packing lists, and bills of lading/air waybills, importing HS 2931.45 may involve additional documentation depending on the importing country's chemical regulations. While not universally required for all chemicals, importers should be prepared for potential requests for a Safety Data Sheet (SDS) or Material Safety Data Sheet (MSDS) to comply with chemical safety and hazard communication standards (e.g., OSHA in the US, REACH in the EU). Some countries may also require specific import permits or end-use declarations if the substance is identified as a precursor for controlled substances or has dual-use potential, although this is less common for this specific compound unless it's part of a broader regulatory concern. Customs brokers should confirm these requirements with the importer and relevant national authorities prior to shipment.
What is the potential impact of a 25% duty rate on HS 2931.45, and under what circumstances might such a rate be applied?
A 25% duty rate on HS 2931.45 represents a significantly higher tariff compared to typical MFN rates (e.g., 6.0% or 6.5%). Such a rate is generally applied under specific, often punitive, circumstances. Common scenarios include: 1) Section 301 tariffs imposed by the United States on goods from specific countries (e.g., China) as a result of trade disputes; 2) Anti-dumping or countervailing duties levied when a country determines that goods are being imported at unfairly low prices or with unfair subsidies, harming domestic industries; 3) Retaliatory tariffs imposed by a country in response to trade actions by another country; or 4) 'Column 2' rates applied to goods from countries that do not have MFN status with the importing nation. Importers must verify the country of origin and any active trade measures that could trigger such elevated duties, as these can drastically impact landed costs and market competitiveness.