HS code · 6-digit subheading
HS Code 2931.51 – Halogenated organo-phosphorous derivatives; methylphosphonic dichloride
HS code 2931.51 is the 6-digit subheading for halogenated organo-phosphorous derivatives, methylphosphonic dichloride. It is used for methylphosphonic dichloride, flame retardant intermediate, pesticide precursor, chemical synthesis reagent and polymer additive precursor.
What HS 2931.51 covers
HS code 293151 specifically covers methylphosphonic dichloride (MPDC), a critical halogenated organo-phosphorous derivative. MPDC is a highly reactive and toxic chemical intermediate, primarily used in the synthesis of various products, including flame retardants, pesticides, and certain specialty polymers. Due to its dual-use potential (also a precursor for chemical warfare agents), its international trade is subject to strict controls and regulations under conventions like the Chemical Weapons Convention. Importers are typically specialized chemical manufacturers and defense-related industries, while exporters are a limited number of chemical companies with the necessary licenses and security protocols. Key aspects of trade involve rigorous documentation, end-user declarations, and compliance with international non-proliferation treaties.
- Covers
- Methylphosphonic dichloride
- Flame retardant intermediate
- Pesticide precursor
- Chemical synthesis reagent
- Polymer additive precursor
- Examples
- Lanxess (Additives)
- ICL Group (Performance Products)
- specialty chemical manufacturers with CWC compliance
- Dow Chemical (historical)
Codes often confused with 2931.51
Common mistake. MPDC can be confused with other phosphonic halides like propylphosphonic dichloride (2931.52) or even non-organic phosphorus halides (e.g., phosphorus oxychloride 2812.10) if the organic methyl group is overlooked.
Top exporters and importers of HS code 293151, 2025
In 2025, the largest exporter of HS code 293151 in UN Comtrade data was Belgium, with 89% of world exports; the largest importer in UN Comtrade data was the United States, with 88% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Top exporters 2025 · share of world exports
- 1 Belgium $154K 89% of world exports
- 2 United Kingdom $17K 9.9% of world exports
- 3 Hungary $2K 0.9% of world exports
World total: $173K Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United States $205K 88% of world imports
- 2 Oman $10K 4.3% of world imports
- 3 Poland $7K 2.9% of world imports
World total: $232K Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM code for 2931.51
Brazil does not split HS 2931.51: its NCM code is 2931.51.00.
All Brazil NCM codes in heading 29.31 →
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text is official; the English is our translation.
Questions about HS 2931.51
What is HS code 293151?
HS code 293151 is a 6-digit subheading in the Harmonized System that covers: Halogenated organo-phosphorous derivatives; methylphosphonic dichloride. HS code 293151 specifically covers methylphosphonic dichloride (MPDC), a critical halogenated organo-phosphorous derivative. MPDC is a highly reactive and toxic chemical intermediate, primarily used in the synthesis of various products, including flame retardants, pesticides, and certain specialty polymers. Due to its dual-use potential (also a precursor for chemical warfare agents), its international trade is subject to strict controls and regulations under conventions like the Chemical Weapons Convention. Importers are typically specialized chemical manufacturers and defense-related industries, while exporters are a limited number of chemical companies with the necessary licenses and security protocols. Key aspects of trade involve rigorous documentation, end-user declarations, and compliance with international non-proliferation treaties.
What products fall under HS code 293151?
Methylphosphonic dichloride, flame retardant intermediate, pesticide precursor, chemical synthesis reagent, polymer additive precursor
What are common misclassifications for HS code 293151?
MPDC can be confused with other phosphonic halides like propylphosphonic dichloride (2931.52) or even non-organic phosphorus halides (e.g., phosphorus oxychloride 2812.10) if the organic methyl group is overlooked.
Which countries are the top exporters of goods under HS code 293151?
In 2025, the top exporters of HS code 293151 in UN Comtrade data were Belgium ($154K, 89% of world exports), the United Kingdom ($17K) and Hungary ($2K). World exports came to about $173K, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of goods under HS code 293151?
In 2025, the top importers of HS code 293151 in UN Comtrade data were the United States ($205K, 88% of world imports), Oman ($10K) and Poland ($7K). World imports came to about $232K, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
How is HS code 293151 structured?
HS code 293151 is a 6-digit subheading under the Harmonized System. The first 2 digits (29) identify the chapter, digits 3-4 (31) identify the heading, and digits 5-6 (51) specify the subheading. This code is standardized globally by the World Customs Organization.
What is the Brazil NCM code for HS code 293151?
In Brazil, HS code 293151 is NCM 2931.51.00. The last two digits are 00 because Brazil does not split this HS code further.