If you've purchased a bottle of water this week, you might have paid a little extra for it.

That's because all bottled water sales in Washington State became subject to sales or use tax on Tuesday.

Bottled water is classified as any water that's sold in a safety-sealed container. It includes water that's delivered in a reusable container, but it does not include water that comes from a self-service dispenser.

All stores must collect the sales tax unless the purchase is made using the Supplemental Nutrition Assistance Program (SNAP), which used to be known as the food stamp program, according to the Washington Department of Revenue.

If you don't have a source of safe water, or if you have a prescription for bottled water, you can claim exemption from the sales tax and file for a refund. To be eligible for the refund, the total amount of sales tax paid on bottled water must exceed $25 and a receipt must show proof.

Learn more about the tax.