How Often Should You Wash Your Water Bottle?

The honest answer: ideally every day, realistically as often as you can manage — and definitely don't let it go for days. A water bottle stays damp inside, which is exactly the environment where bacteria and film build up. Even "just water" leaves enough residue, plus backwash from your mouth, to warrant a daily wash.

A practical routine: a proper wash with soap and a bottle brush daily (or near-daily), with extra attention to the lid and gasket where buildup hides, and a deeper baking-soda soak every week or two. Always air-dry with the lid off rather than capping it wet. If you only ever rinse it, odor and film will eventually win. A non-porous steel interior makes it easier, since it cleans up fully. More in keeping water clean on the go.

Try the Steely vacuum flask.