Product classification

HS code for Calcium hypophosphite: 2835.10

Phosphinates (hypophosphites) and phosphonates (phosphites), whether or not chemically defined.

Classification of calcium hypophosphite under HS 2835.10

Calcium hypophosphite is classified under HS code 2835.10, which specifically covers phosphinates (hypophosphites) and phosphonates (phosphites). This classification is part of Chapter 28, which deals with inorganic chemicals. Heading 2835 is structured to include phosphinates, phosphonates, phosphates, and polyphosphates. Calcium hypophosphite, with the chemical formula Ca(H2PO2)2, is the calcium salt of hypophosphorous acid. Under the Harmonized System, the first subheading (2835.10) is dedicated to the salts of phosphinic and phosphonic acids. Since calcium hypophosphite is a phosphinate, it is accurately placed here. The classification is determined by the chemical structure of the anion; hypophosphites contain phosphorus in a lower oxidation state compared to phosphates. To qualify for this code, the substance must be a separate chemically defined compound. It is widely used as a flame retardant in polymers and as a nutritional supplement in animal feed, but its chemical identity as a phosphinate remains the primary driver for its 2835.10 classification.

Covers
  • Calcium hypophosphite technical grade
  • Calcium hypophosphite pharmaceutical grade
  • Calcium hypophosphite used as a flame retardant additive
  • Calcium hypophosphite for animal nutrition
Also under 2835.10
  • Electroless Nickel Plating Solutions (Atotech, MacDermid Enthone)
  • Polymer Stabilizers (BASF, Songwon)
  • Antioxidants (various chemical suppliers)
  • Chemical Intermediates

Codes often confused with 2835.10

Common mistake. The most common misclassification for this product is under HS code 2835.26, which covers phosphates of calcium. While both contain calcium and phosphorus, phosphates (2835.26) are salts of phosphoric acid, whereas hypophosphites (2835.10) are salts of phosphinic acid. Another potential error is 2835.29, which is a residual category for other phosphates. It is critical to identify the oxidation state of the phosphorus to distinguish between these subheadings.

2835.26Phosphates; of calcium n.e.c. in item no. 2835.25, whether or not chemically defined2835.29Phosphates; (other than of mono- or disodium, other than of potassium or of calcium hydrogenorthophosphate (dicalcium phosphate) and excluding other phosphates of calcium), whether or not chemically defined

Top exporters and importers of HS 283510 (the code used for calcium hypophosphite), 2025

In 2025, the largest exporter of HS 283510 (the code used for calcium hypophosphite) in UN Comtrade data was China, with 43% of world exports; the largest importer in UN Comtrade data was Malaysia, with 11% 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 283510, not only calcium hypophosphite.

Top exporters 2025 · share of world exports

  1. 1 China $122M
  2. 2 Indonesia $107M
  3. 3 Switzerland $8.0M

World total: $284M Reported figures on UN Comtrade ↗

Top importers 2025 · share of world imports

  1. 1 Malaysia $21M
  2. 2 United States $20M
  3. 3 Germany $16M

World total: $181M 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 codes for calcium hypophosphite

Brazil splits HS 2835.10 into 4 NCM codes. Pick the one that matches your product:

Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.

Questions about calcium hypophosphite

What is the HS code for Calcium hypophosphite?

The HS code for Calcium hypophosphite is 283510 (Phosphinates (hypophosphites) and phosphonates (phosphites), whether or not chemically defined). The HS code for calcium hypophosphite is 2835.10, covering phosphinates and phosphonates.

How do I classify Calcium hypophosphite for customs?

Calcium hypophosphite is classified under HS code 283510 — Phosphinates (hypophosphites) and phosphonates (phosphites), whether or not chemically defined. This is a 6-digit subheading level code.

Can calcium hypophosphite be classified in Chapter 29?

No, because calcium hypophosphite is an inorganic salt, it is excluded from Chapter 29 (organic chemicals) and must be classified in Chapter 28.

Which countries are the top exporters of calcium hypophosphite (HS 283510)?

In 2025, the top exporters of HS 283510 (the code used for calcium hypophosphite) in UN Comtrade data were China ($122M, 43% of world exports), Indonesia ($107M) and Switzerland ($8.0M). World exports came to about $284M, 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 calcium hypophosphite (HS 283510)?

In 2025, the top importers of HS 283510 (the code used for calcium hypophosphite) in UN Comtrade data were Malaysia ($21M, 11% of world imports), the United States ($20M) and Germany ($16M). World imports came to about $181M, 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 Calcium hypophosphite the same in all countries?

The base HS code 283510 for Calcium hypophosphite 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 calcium hypophosphite in Brazil?

Brazil splits HS 283510 into 4 NCM codes, so the right one for calcium hypophosphite depends on the product's details: 2835.10.11 (Sodium phosphinate (hypophosphite)), 2835.10.19 (Other phosphinates (hypophosphites)), 2835.10.21 (Dibasic lead phosphonate (phosphite)), 2835.10.29 (Other phosphonates (phosphites)).