Heading 2839

Silicates; commercial alkali metal silicates

4 declarable lines

Heading 2839 covers silicates and commercial alkali metal silicates. The heading is split first by metal: sodium silicates in 2839.11 and 2839.19, everything else in 2839.90. Sodium silicates are further split between sodium metasilicates and other sodium silicates, while the residual group is split between potassium and other.

Products in this heading

Sodium metasilicate, anhydrous or hydrated
Sodium silicate solution (water glass) used as a binder or detergent builder
Sodium orthosilicate
Potassium silicate used in welding electrode coatings
Commercial alkali metal silicate mixtures sold dry
Sodium silicate powder for cements and refractories

How to choose the right subheading

Identify the metal in the silicate: sodium, potassium, or another metal.
For sodium silicates, decide whether the product is a metasilicate or another sodium silicate.
Check whether the goods are sold as commercial alkali metal silicates, since that commercial form is named in the heading text.
Confirm the product is a silicate salt and not silica, a hydroxide, or a carbonate.

Often confused with

Silica (silicon dioxide) powder or gel
Silicon dioxide is an oxygen compound of a nonmetal, not a silicate salt.
Heading 2811
Sodium hydroxide (caustic soda)
A hydroxide of sodium, classified in the hydroxide heading, not with silicates.
Heading 2815
Aluminum hydroxide
Aluminum oxide and hydroxide have their own heading.
Heading 2818
Sodium carbonate (soda ash)
Carbonates are classified separately from silicates.
Heading 2836
Sodium borate (borax)
Borates and peroxoborates are classified in heading 2840.
Heading 2840

Frequently asked questions

What is the HTS code for sodium metasilicate?

Sodium metasilicates are classified under 2839.11.00.00, with a general (MFN) rate of 1.1%.

What is the duty on potassium silicate?

Potassium silicates fall under 2839.90.10.00, and the general (MFN) rate is 3.1%.

How do I classify a sodium silicate that is not a metasilicate?

Other sodium silicates go in 2839.19.00.00, which carries a general (MFN) rate of 1.1%. Silicates of metals other than sodium or potassium go in 2839.90.50.00 at a general (MFN) rate of 3.1%.

Guide written from the official schedule text. Rates quoted are general (MFN) rates; check the line page for trade agreement rates and the classification of your exact product.