How to choose and clean a reusable water bottle

2026-10-30

For most people, the best reusable bottle is a stainless steel or glass one of about 500 to 750 ml (17 to 25 fl oz), with a wide enough opening to clean and a lid with as few hidden parts as possible. Rinse it and let it dry every day, wash it with hot soapy water and a brush every day or two, and give it a deeper clean once a week. The material matters less than how often you clean it and whether you actually carry it.

Why a reusable bottle helps

A bottle you like and keep within reach is one of the simplest ways to drink more, because water becomes the easy default instead of something you have to go and get. It's also cheaper than buying bottled water, and in most of Europe and North America tap water is safe and tightly regulated (more in tap water vs bottled water).

Choosing the material

Stainless steel

The most popular choice, for good reasons.

Pros: durable, doesn't hold on to flavors much, no plastic in contact with your water. Double-walled vacuum-insulated bottles keep water cold for many hours and can carry hot tea in winter.
Cons: heavier than plastic, can dent, and you can't see how much is left or whether the inside is clean.
Look for: food-grade stainless steel (often labeled 18/8 or 304). Some insulated bottles shouldn't go in the dishwasher, so check the instructions.

Glass

Pros: completely inert, no taste, easy to see when it's clean, dishwasher-safe.
Cons: heavy and breakable. A silicone sleeve helps.
Best for: your desk, home, or office rather than hiking or the gym.

Plastic

Pros: light, cheap, often transparent so you can see your progress. Good for sport and children.
Cons: scratches over time (scratches are harder to clean), can keep smells, and many aren't suitable for hot drinks.
About BPA: bisphenol A was long used in hard polycarbonate bottles. Regulators disagree about the risk at everyday exposure levels: the US FDA considers its approved uses safe, while EFSA concluded in 2023 that dietary exposure is a health concern and lowered its tolerable daily intake sharply. The European Commission then banned BPA in food contact materials, with transition periods for existing products. Most reusable plastic bottles sold today are labeled BPA-free (often made from copolyester such as Tritan, or polypropylene). If you want to avoid the question altogether, choose steel or glass.

Aluminum and others

Aluminum bottles are light but need an internal coating, and older coatings sometimes contained BPA, so newer stainless steel is usually the simpler choice. Collapsible silicone bottles are handy for travel but harder to clean thoroughly.

Can you reuse single-use plastic bottles?

Refilling a disposable PET bottle a few times isn't dangerous, but they're thin, scratch easily and are hard to clean properly, so they're not a good long-term bottle. Recycle them and use a real reusable one.

Choosing the size

Think about where you'll refill and what your daily goal is.

350 to 500 ml (12 to 17 fl oz): fits in a bag or cup holder, easy to carry all day. You'll refill often, which isn't a bad thing if you're near a tap.
750 ml (25 fl oz): a good all-round size for a desk or the gym.
1 liter or more (34 fl oz+): good when refills are hard to come by: long drives, hikes, shifts without breaks. Heavier when full.

A handy trick is to count your goal in bottles. If your goal is 2 liters, that's four 500 ml bottles, or two refills of a 1 liter bottle. "One bottle before lunch, one after" is easier to stick to than counting glasses. To work out your own goal, see how to calculate your water intake from body weight. Remember that other drinks and food count too, so your bottle doesn't need to cover everything.

The lid matters more than you think

Lids are where dirt hides.

Simple screw caps are the easiest to clean.
Wide mouths (around 5 cm or more) let you fit a brush and ice cubes inside.
Straw lids and bite valves are convenient but have narrow tubes and soft parts that trap moisture. Choose one that comes apart completely, and clean every part.
Spare seals: silicone rings collect residue; good brands sell replacements.

How to clean a reusable bottle

Every day

Empty the bottle at the end of the day instead of leaving water in it overnight.
Rinse it and the lid with warm water.
Leave it open, upside down or on its side, to air-dry completely. Moisture trapped under a closed lid is what makes bottles smell.

Every day or two (and always after anything but water)

Take the lid apart: seals, straws and valves.
Wash everything with hot water and dish soap. Use a bottle brush for the inside and a small straw brush for the lid and straw.
Rinse well and let all parts air-dry before reassembling.

If you put juice, smoothies, sports drinks or milk in your bottle, wash it the same day. Sugar and protein feed bacteria much faster than plain water does.

Once a week: deep clean

Dishwasher: if the manufacturer says the bottle and lid are dishwasher-safe, a hot cycle is the simplest option. Put small parts in the top rack or a basket.
Bleach solution: for bottles that can't go in the dishwasher, you can use the method the CDC recommends for water containers: wash with soap first, then add 5 ml (1 teaspoon) of unscented household bleach per liter of water, close and shake so it touches every surface, wait at least 30 seconds, pour it out and let it air-dry or rinse with clean water. Don't use bleach on materials the manufacturer warns against.
Smells or limescale: soak with a solution of white vinegar and water, or a spoon of baking soda in warm water, then wash and rinse. These help with odors and mineral deposits; they're not a substitute for proper washing.

Never mix bleach with vinegar or other cleaning products: the combination releases toxic gas. Use one method at a time and rinse between them.

When to replace a bottle

cracks, deep scratches or a cloudy surface you can't clean
a smell or taste that remains after a deep clean
black spots in seals or straws that don't come off (replace the part, or the bottle)
a damaged insulating wall: if a steel bottle no longer keeps drinks cold, the vacuum has failed

Make the bottle work for you

A bottle only helps if you use it. A few habits that make it stick:

Fill it the night before and put it by your keys, or fill it first thing in the morning.
Keep it in sight on your desk; out of sight usually means out of mind. More ideas in how to drink enough water at work.
Refill it every time you finish it, not when you remember.
Log each bottle as you finish it, so you know where you stand.

That last step takes one tap in Water Tracker: you can log a glass, a bottle or any custom amount, so it's worth setting the amount to match your own bottle. Reminders go quiet once you've reached your goal.

Bottom line

Choose a bottle you'll actually carry: stainless steel or glass if you want to avoid plastic, a BPA-free plastic one if weight matters most, in a size that matches your day and your refill options. Keep it clean with a daily rinse and air-dry, regular hot soapy washes with a brush, and a weekly deep clean, paying special attention to the lid.

This article is general information, not medical advice. If you have a health condition, are pregnant or take medication, ask your doctor how much you should drink.