Product classification
HS code for STPP: 2835.31
Polyphosphates, sodium triphosphate (sodium tripolyphosphate), whether or not chemically defined.
Classification of STPP under HS 2835.31
STPP, or Sodium Triphosphate (also known as sodium tripolyphosphate), is classified under HS code 2835.31. This classification falls under Chapter 28, which covers inorganic chemicals and precious metal compounds. Heading 2835 is dedicated to phosphinates (hypophosphites), phosphonates (phosphites), and phosphates, including polyphosphates. STPP is a polyphosphate, and subheading 2835.31 specifically identifies 'Sodium triphosphate (sodium tripolyphosphate).' This chemical is widely used in industrial applications, most notably as a builder in domestic and industrial detergents, and as a preservative in the food industry. The classification is based on its chemical structure as a salt of triphosphoric acid. Whether the product is in its anhydrous form or the hexahydrate form, it remains under this specific subheading as long as it is a separate chemically defined compound.
- Covers
- Technical grade sodium tripolyphosphate
- Food grade sodium triphosphate
- Anhydrous STPP powder
- STPP hexahydrate
- Granular sodium triphosphate for detergents
- Also under 2835.31
- P&G (detergents)
- Unilever (detergents)
- Innophos (food ingredients)
- ICL (industrial chemicals)
Codes often confused with 2835.31
Common mistake. A common misclassification for STPP is HS code 3402.20 or 3402.90, which covers detergent preparations. While STPP is a major component of many detergents, the pure chemical itself must be classified in Chapter 28. Only when it is mixed with surfactants and other additives to form a finished cleaning product does it move to Chapter 34. Another error is confusing it with other sodium phosphates, such as Disodium Phosphate, which is classified under 2835.22. It is critical to distinguish between simple phosphates (orthophosphates) and polyphosphates like STPP to ensure the correct subheading is applied.
Top exporters and importers of HS 283531 (the code used for STPP), 2025
In 2025, the largest exporter of HS 283531 (the code used for STPP) in UN Comtrade data was China, with 44% of world exports; the largest importer in UN Comtrade data was the United States, with 16% 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 283531, not only STPP.
Top exporters 2025 · share of world exports
- 1 China $224M 44% of world exports
- 2 Belgium $95M 19% of world exports
- 3 Canada $41M 8.2% of world exports
World total: $504M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United States $83M 16% of world imports
- 2 India $42M 8.0% of world imports
- 3 Brazil $28M 5.4% of world imports
World total: $519M 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 STPP
Brazil splits HS 2835.31 into 2 NCM codes. Pick the one that matches your product:
- 2835.31.10Food-grade sodium tripolyphosphate
- 2835.31.90Other sodium triphosphate (tripolyphosphate)
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about STPP
What is the HS code for STPP?
The HS code for STPP is 283531 (Polyphosphates; sodium triphosphate (sodium tripolyphosphate), whether or not chemically defined). The HS code for Sodium Triphosphate (STPP) is 2835.31.
How do I classify STPP for customs?
STPP is classified under HS code 283531 — Polyphosphates; sodium triphosphate (sodium tripolyphosphate), whether or not chemically defined. This is a 6-digit subheading level code.
Does food-grade STPP have a different HS code?
No, both technical-grade and food-grade sodium triphosphate are classified under HS code 2835.31 as they are the same chemical compound.
Which countries are the top exporters of STPP (HS 283531)?
In 2025, the top exporters of HS 283531 (the code used for STPP) in UN Comtrade data were China ($224M, 44% of world exports), Belgium ($95M) and Canada ($41M). World exports came to about $504M, 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 STPP (HS 283531)?
In 2025, the top importers of HS 283531 (the code used for STPP) in UN Comtrade data were the United States ($83M, 16% of world imports), India ($42M) and Brazil ($28M). World imports came to about $519M, 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 STPP the same in all countries?
The base HS code 283531 for STPP 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 STPP in Brazil?
Brazil splits HS 283531 into 2 NCM codes, so the right one for STPP depends on the product's details: 2835.31.10 (Food-grade sodium tripolyphosphate), 2835.31.90 (Other sodium triphosphate (tripolyphosphate)).