SALT Report 2118 – The Washington Department of Revenue issued guidance regarding the taxability of chemicals used to treat drinking water.
Chemicals that remain in the water after treatment and are present in the water when it is delivered to customers may be purchased exempt. Examples include: fluoride and chlorine.
Chemicals consumed in the process of treating drinking water and are not present in the water when it is delivered to customers are taxable. Examples include: ozone.
You must have a reseller permit to claim the exemption. If you have previously paid sales or use tax on exempt water treatment chemicals, you may apply for a refund online.
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