Washington state currently taxes bottled water, but it hasn’t always.
Bottled water became exempt from Washington sales and use tax on January 1, 2004, so the Evergreen State would be in compliance with the Streamlined Sales and Use Tax Agreement (SSUTA). Then on June 1, 2010, shortly after the SSUTA was amended to allow member states to tax bottled water, Washington began taxing bottled water again.
The tax on bottled water was set to expire in 2013, but in November 2010, Washington voters took the matter into their own hands. Initiative 1107 repealed state and local sales taxes on bottled water (and candy and gum). Water therefore became exempt from Washington sales and use tax effective December 2, 2010, just six months after it became taxable.
But hang on to your caps because bottled water became subject to Washington sales and use tax again starting August 1, 2017.
Washington does allow a sales tax refund for taxpayers who purchase bottled water with a prescription, and for those whose primary source of drinking water is unsafe. To qualify for a refund, a taxpayer must have paid at least $25 in sales tax for eligible bottled water, and the refund must be requested within four years of the end of the year in which the tax was paid.