2831.10.10.00
Sodium formaldehyde sulfoxylate
Classification path
- Dithionites and sulfoxylates
- Of sodium
- Sodium formaldehyde sulfoxylate
Rates of duty
- General (MFN)
- Free
- Column 2Cuba, North Korea, Russia, Belarus
- 35%
- Unit of quantity
- kg
Related lines in heading 2831
About heading 2831
Dithionites and sulfoxylates
Heading 2831 covers dithionites (also called hydrosulfites) and sulfoxylates, which are inorganic sulfur-oxygen salts used mainly as reducing and bleaching agents. The heading splits first by metal: lines under 2831.10 are for sodium compounds, and 2831.90.00.00 covers all other dithionites and sulfoxylates. Within the sodium group, sodium formaldehyde sulfoxylate has its own free line, and all other sodium dithionites and sulfoxylates fall on the residual 5.5% line.
Full guide to heading 2831Products in this heading
- Sodium dithionite (sodium hydrosulfite), the common reductive bleach for textiles and pulp
- Sodium formaldehyde sulfoxylate
- Zinc dithionite
- Potassium dithionite
- Calcium dithionite
- Sodium sulfoxylate salts used as polymerization activators
Frequently asked questions
What is the HTS code for sodium dithionite?
Sodium dithionite (sodium hydrosulfite) is classified under 2831.10.50.00, the residual line for sodium compounds of this heading. The general (MFN) rate for that line is 5.5%.
What is the duty on sodium formaldehyde sulfoxylate?
Sodium formaldehyde sulfoxylate falls under 2831.10.10.00. The general (MFN) rate for that line is Free.
How do I classify a dithionite that is not a sodium salt?
Non-sodium dithionites, such as zinc or potassium dithionite, go in 2831.90.00.00. The general (MFN) rate for that line is 5.5%.
Source: USITC Harmonized Tariff Schedule, retrieved October 21, 2026.