HS code · 6-digit subheading
HS Code 2904.35 – Derivatives of hydrocarbons; salts of perfluorooctane sulphonic acid n.e.c in heading no. 2904, whether or not halogenated
HS code 2904.35 is the 6-digit subheading for derivatives of hydrocarbons, salts of perfluorooctane sulphonic acid n.e.c in heading no. 2904, whether or not halogenated. It is used for sodium perfluorooctane sulfonate, calcium perfluorooctane sulfonate, magnesium perfluorooctane sulfonate, zinc perfluorooctane sulfonate and organic amine salts of PFOS.
What HS 2904.35 covers
This HS code serves as a residual category for salts of Perfluorooctane Sulphonic Acid (PFOS) not specifically enumerated in other subheadings under 2904. This includes various other metallic or organic salts of PFOS beyond ammonium, lithium, and potassium. Historically, these "not elsewhere specified" PFOS salts would have been used in similar applications to their more common counterparts, leveraging their surfactant properties for water and oil repellency in textiles, paper, fire-fighting foams, and metal plating. However, like all PFOS derivatives, these compounds are now subject to stringent international regulations, including bans and restrictions under the Stockholm Convention, due to their environmental persistence, bioaccumulation, and potential toxicity. Consequently, global trade in these miscellaneous PFOS salts is extremely limited, primarily confined to specific, critically exempted uses or for the management of existing stockpiles. Importers and exporters must adhere to strict international chemical control regulations and provide thorough documentation for any permitted transactions.
- Covers
- Sodium perfluorooctane sulfonate
- Calcium perfluorooctane sulfonate
- Magnesium perfluorooctane sulfonate
- Zinc perfluorooctane sulfonate
- Organic amine salts of PFOS
- Examples
- 3M (historical producer)
- Chemours (fluorochemicals, but PFOS salts largely restricted)
- Daikin (fluorochemicals, but PFOS salts largely restricted)
Codes often confused with 2904.35
Common mistake. This "n.e.c." code is specifically for PFOS salts not covered by 290432, 290433, or 290434; misclassification could occur if a specific PFOS salt is incorrectly placed here instead of its dedicated subheading, or if other PFAS compounds are mistakenly included.
Top exporters and importers of HS code 290435, 2025
In 2025, the largest exporter of HS code 290435 in UN Comtrade data was the United States, with 78% of world exports; the largest importer in UN Comtrade data was Canada, with 83% 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 United States $766K 78% of world exports
- 2 South Africa $129K 13% of world exports
- 3 France $73K 7.4% of world exports
World total: $985K Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Canada $1.0M 83% of world imports
- 2 Zambia* ~$101K 8.3% of world imports · partner records ↗
- 3 Malawi $49K 4.0% of world imports
World total: $1.2M 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 2904.35
Brazil does not split HS 2904.35: its NCM code is 2904.35.00.
All Brazil NCM codes in heading 29.04 →
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text is official; the English is our translation.
Questions about HS 2904.35
What is HS code 290435?
HS code 290435 is a 6-digit subheading in the Harmonized System that covers: Derivatives of hydrocarbons; salts of perfluorooctane sulphonic acid n.e.c in heading no. 2904, whether or not halogenated. This HS code serves as a residual category for salts of Perfluorooctane Sulphonic Acid (PFOS) not specifically enumerated in other subheadings under 2904. This includes various other metallic or organic salts of PFOS beyond ammonium, lithium, and potassium. Historically, these "not elsewhere specified" PFOS salts would have been used in similar applications to their more common counterparts, leveraging their surfactant properties for water and oil repellency in textiles, paper, fire-fighting foams, and metal plating. However, like all PFOS derivatives, these compounds are now subject to stringent international regulations, including bans and restrictions under the Stockholm Convention, due to their environmental persistence, bioaccumulation, and potential toxicity. Consequently, global trade in these miscellaneous PFOS salts is extremely limited, primarily confined to specific, critically exempted uses or for the management of existing stockpiles. Importers and exporters must adhere to strict international chemical control regulations and provide thorough documentation for any permitted transactions.
What products fall under HS code 290435?
Sodium perfluorooctane sulfonate, Calcium perfluorooctane sulfonate, Magnesium perfluorooctane sulfonate, Zinc perfluorooctane sulfonate, Organic amine salts of PFOS
What are common misclassifications for HS code 290435?
This "n.e.c." code is specifically for PFOS salts not covered by 290432, 290433, or 290434; misclassification could occur if a specific PFOS salt is incorrectly placed here instead of its dedicated subheading, or if other PFAS compounds are mistakenly included.
Which countries are the top exporters of goods under HS code 290435?
In 2025, the top exporters of HS code 290435 in UN Comtrade data were the United States ($766K, 78% of world exports), South Africa ($129K) and France ($73K). World exports came to about $985K, 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 290435?
In 2025, the top importers of HS code 290435 in UN Comtrade data were Canada ($1.0M, 83% of world imports), Zambia (about $101K) and Malawi ($49K). World imports came to about $1.2M, 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 290435 structured?
HS code 290435 is a 6-digit subheading under the Harmonized System. The first 2 digits (29) identify the chapter, digits 3-4 (04) identify the heading, and digits 5-6 (35) specify the subheading. This code is standardized globally by the World Customs Organization.
What is the Brazil NCM code for HS code 290435?
In Brazil, HS code 290435 is NCM 2904.35.00. The last two digits are 00 because Brazil does not split this HS code further.