How to Clean a Water Bottle to Prevent Germs, Mold, and Buildup

Jun 16, 2023

Your water bottle may go with you everywhere, but there’s one thing it can’t do—clean itself.

Emily Estep is a plant biologist and journalist who has worked for a variety of online news and media outlets, writing about and editing topics that range from film and beauty to science and the automobile industry. Her plant biology degree has a focus on sustainable agriculture, and she's an expert on growing your own food, environmental sciences, and all topics relating to houseplants.

Is there anything as underrated as your reusable water bottle? This handy item goes with you to the gym, your desk, the grocery store, and on daily dog walks. It might be in your favorite color and keep ice water cold for hours on end, but it might also be host to bacteria, buildup, and even mold. With so many reusable types available, it's sometimes confusing to understand how to clean a water bottle.

Experts say you should wash your water bottle after every use. According to researchers at Treadmill Reviews, athletes' water bottles, on average, host 313,499 colony-forming units (CFU) per square centimeter. For comparison, the average pet toy has just 2,937 CFU per square centimeter. That's a lot of germs. Plus, any warm, damp place is a breeding ground for mold growth. So check out our tips for how to clean a water bottle to ensure you're drinking from a safe, clean vessel.

BHG / Elizabeth Seely

Some water bottles are dishwasher safe. If so, toss yours into the dishwasher every time you run a cycle. However, even if the base of the bottle can go in the dishwasher, the lid might not. If your water bottle isn't dishwasher-safe, use these common cleaning agents to get the job done.

For everyday washes, warm, soapy water will do the trick.

Vinegar is our favorite go-to cleaning agent.

This is a particularly good way to clean a stainless steel water bottle.

BHG / Elizabeth Seely

For hard-to-clean grime and mildew, consider cleaning your water bottle with bleach.

If your bottle is dishwasher friendly, we suggest running it through a cycle.

New water bottles come with all the bells and whistles, including reusable straws, BPA-free materials, insulated double-wall interiors, and more. However, these features come with special cleaning issues. Here's how to clean specific types of water bottles when traditional cleaning techniques just won't suffice.

Water bottles that feature lids with built-in straws with a soft plastic bite valve ($16, Amazon) are great for eliminating spills mid-workout. However, that handy feature can also harbor some serious germs and mold.

According to CamelBak, you should clean a soft plastic bite valve by removing it from the lid.

Most tumblers can be cleaned in the dishwasher or with the above water bottle cleaning methods. The reusable straws, however, need special care. We recommend purchasing a set of straw brushes. When you're ready to clean your tumbler straw, rinse it with warm water, place a small amount of dish soap on your straw brush, and scrub the interior and exterior. If that's not getting the job done, you can add baking soda, which will act as an abrasive.

Travel mugs are typically used for hot drinks, but several water bottle companies use the same flip-top lid. If you plan to wash your travel mug in the dishwasher, use the top rack. However, you'll want to hand wash it if it's insulated. Wash the lid by removing the rubber seal around the base and scrubbing it with warm, soapy water. Be sure to get every nook and cranny of the top, as it can be a hot spot for mold.