Product classification
HS code for Heavy water: 2845.10
Heavy water (deuterium oxide).
Classification of heavy water under HS 2845.10
Heavy water, scientifically known as deuterium oxide (D2O), is classified under HS code 2845.10. This classification falls within Chapter 28, which covers inorganic chemicals and precious metal compounds. Specifically, heading 2845 is reserved for isotopes other than those of heading 2844 and their compounds. Heavy water is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium. Because it is an isotopic compound rather than a standard chemical or a radioactive isotope (which would fall under 2844), it is explicitly placed in 2845.10. This substance is primarily used in certain types of nuclear reactors as a neutron moderator and in scientific research for NMR spectroscopy. The classification is straightforward because deuterium oxide is the only product mentioned in this specific subheading, reflecting its unique physical properties and strategic importance.
- Covers
- Deuterium oxide (D2O)
- Heavy water (nuclear grade)
- Heavy water (laboratory grade)
- Solutions of deuterium oxide in water
- Also under 2845.10
- Cameco (Canada)
- Indian Heavy Water Board
- Sigma-Aldrich (for research grade D2O).
Codes often confused with 2845.10
Common mistake. Heavy water is occasionally misclassified under 2201.90 (ordinary water) by those unfamiliar with its chemical properties. However, because it is an isotopic compound, Chapter 28 takes precedence over Chapter 22. It may also be confused with 2844.40 if the user incorrectly assumes it is radioactive; while used in nuclear reactors, pure heavy water itself is not a radioactive isotope and thus belongs in 2845.10.
Top exporters and importers of HS 284510 (the code used for heavy water), 2025
In 2025, the largest exporter of HS 284510 (the code used for heavy water) in UN Comtrade data was India, with 45% of world exports; the largest importer in UN Comtrade data was the United States, with 40% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Figures cover everything classified under HS 284510, not only heavy water.
Top exporters 2025 · share of world exports
- 1 India $74M 45% of world exports
- 2 Canada $32M 20% of world exports
- 3 Iran* ~$23M 14% of world exports · partner records ↗
World total: $165M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United States $67M 40% of world imports
- 2 China $37M 22% of world imports
- 3 Switzerland $16M 9.6% of world imports
World total: $164M 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 marked * did not, so their figures add up what other countries recorded trading with them, and their exports are valued at buyers' CIF prices. 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 heavy water
Brazil classifies heavy water under NCM 2845.10.00: HS 2845.10 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about heavy water
What is the HS code for Heavy water?
The HS code for Heavy water is 284510 (Heavy water (deuterium oxide)). The specific HS code for heavy water (deuterium oxide) is 2845.10.
How do I classify Heavy water for customs?
Heavy water is classified under HS code 284510 — Heavy water (deuterium oxide). This is a 6-digit subheading level code.
Is heavy water classified as a hazardous chemical?
While HS classification 2845.10 identifies the substance, its status as a hazardous or controlled material depends on national regulations and its concentration, often requiring export licenses due to its use in nuclear applications.
Which countries are the top exporters of heavy water (HS 284510)?
In 2025, the top exporters of HS 284510 (the code used for heavy water) in UN Comtrade data were India ($74M, 45% of world exports), Canada ($32M) and Iran (about $23M). World exports came to about $165M, 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 heavy water (HS 284510)?
In 2025, the top importers of HS 284510 (the code used for heavy water) in UN Comtrade data were the United States ($67M, 40% of world imports), China ($37M) and Switzerland ($16M). World imports came to about $164M, 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.
Is the HS code for Heavy water the same in all countries?
The base HS code 284510 for Heavy water is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.
What is the NCM code for heavy water in Brazil?
In Brazil, heavy water (HS 284510) is classified under NCM 2845.10.00.