I tested 42 water bottles to find the best for leaks, looks and sustainability: here are my favourites

The Guardian

3 days ago

If you think a water bottle is just a water bottle, it's time to wake up. In 2025, there's a lot riding on your choice of drinking vessel. The heady combination of worrying about the planet and, on a more day-to-day level, staying hydrated has made reusable water bottles a must-have.
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Once the preserve of hikers and gym-goers, water bottles have become a small but significant act of environmental virtue signalling. Not all bottles are created equal, though. Some are insulated, some leak, some weigh as much as a toddler, and some even infuse your water with hydrogen (more on that later). The choice is dizzying.
It's time to lock in, reader. I've dedicated months to finding the best water bottles. I've bored my friends and family with tales of weight v capacity. I've thrown water bottles around my garden. Join me in the quest to stay hydrated and vaguely hopeful about the planet – and find your perfect water bottle along the way.
Best water bottle overall:Owala FreeSip
Best budget water bottle:Ion8 stainless-steel water bottle
Best stainless-steel water bottle:Frank Green ceramic reusable water bottle
Best water bottle for kids:
Yeti Rambler Jr kids' water bottle
Best sustainable water bottle:Ocean Bottle Go water bottle
I've been testing products professionally for more than four years. I've assessed so many things, from tablets and trampolines to slow cookers and SPF. My family has become used to rating anything they come across out of five (not so welcome when it's my cooking that's being rated, if I'm honest).
I've tested kids' water bottles and cups before, and I'm also on a quest to better hydrate myself after several medical professionals told me I'm so dehydrated that I'm virtually desiccated (they didn't use that actual term).
In that quest, I've experienced school bags filled with water, mouldy water bottles that are impossible to clean and straws that melt in the dishwasher. Here, I've included only water bottles that went through my rigorous testing and came out on top. Life is too short to suffer a rubbish water bottle.
I spent two months testing water bottles, trying out 42. I recruited my family as co-testers, and let my three children put the kids' water bottles through what feels like the ultimate test: a day at a British primary school.
During testing, I weighed the water bottles when empty and full. I dropped them from waist height on to a hard floor to see how they withstood the impact. I also put each water bottle on its side in a bag and hung them from my washing line for 30 minutes to see if they leaked. If the water bottles were insulated, I checked how quickly the liquid warmed over a few hours.
As well as performance, I did a deep dive into sustainability. I wanted to see which water-bottle brands were all mouth in the eco-friendly stakes – what initiatives did they have beyond creating a reusable water bottle? And how durable and recyclable were the bottles? After testing the water bottles, I donated them to charity for resale.
Here are the nine water bottles that performed best in my tests.
I challenge you to get through a TikTok doomscroll without coming across an Owala FreeSip water bottle. It's been the 'it' water bottle for a while, and it actually deserves the gen Z hype.
The bottle comes in three sizes: 24oz, 32oz and 40oz. In my opinion, the 24oz (just over 700ml) is a perfect size: it fits in cup holders yet doesn't need refilling every hour. The stainless-steel design is triple insulated and has a one-handed flip-lid opening. What sets the FreeSip apart is the spout – you can sip your drink through a straw or gulp it from the free pour.
Why we love it
This is the water bottle I went back to during and after testing. A FreeSip is sitting next to me as I type this.
Owala sells this bottle in a fun range of colours, so you can find one that fits your style. It's also practical: the FreeSip doesn't weigh much considering it offers decent insulation (it keeps drinks icy for hours, even in a heatwave).
The FreeSip is also easy to clean – its lid screws off and the bottle is wide enough to really get in there and blitz it. The rigid straw is easy to scrub using a bottle brush, and so is the spout. There's a removable silicone seal, which I haven't found harbours any mould; I give this a soak and find it's an easy job.
Most importantly, I can chuck my FreeSip in any bag and be confident it won't leak – I'm even happy to throw it in a bag with my laptop, which I'd be wary about with most other water bottles. It also survived the drop test, and I'm confident it's built to last.
During testing, many of my friends remarked on my FreeSip and then went out and bought their own, becoming converts themselves. OK, it's more pricey than other bottles on this list (especially when you take into account shipping costs), but you'll never get water-bottle envy again.
It's a shame that … the shipping costs and taxes on these water bottles are so high.
Dishwasher safe: lid, yes; bottle body, hand-washBPA free: yesSizes available: 24oz (710ml), 32oz (910ml), 40oz (1.2l)Weight empty (710ml): 390g
Weight filled (710ml): 1.07kg
The Ion8 water bottle offers much of the same functionality as others on this list, but at a fraction of the price. It's stainless steel and has a flip-lid spout, with a carry hook in the lid. It's not thermally insulated, though, which may account for why it's more affordable.
Ion8 produces this water bottle in an array of colours, so you're sure to find something you like. At 400ml capacity, it can be slipped easily into most bags.
Why we love itThis bottle passed most of my testing criteria with flying colours. Perhaps most importantly, it didn't leak in a bag when laid flat for an extended period. It's lightweight too – it offers less capacity than many bottles on this list, but it's great for the commute and chucking in your bag on the run.
My kids also liked it for taking to school and sports clubs. I appreciated that it fitted in my car's cup holder – so many water bottles I tested didn't.
It remained unfazed by the drop test, too, so it's durable. As it's a tip-and-pour bottle rather than a straw water bottle (there's an optional straw included, but I went without), it's easier to clean. I personally found the carry handle uncomfortable to use, though: the loop is small and got stuck on my fingers.
It's a shame that … Ion8 says this is a one-handed opening flip lid, but I found it clunky. I needed two hands to open the bottle, and I usually like to think of myself as fairly dexterous.
Dishwasher safe: yes, on a cool cycleBPA free: yesSizes available: 400ml, 600ml, 1lWeight empty (600ml): 259g (including straw)
Weight filled (600ml): 676g
I'd heard about how indestructible Frank Green water bottles are, so I was keen to see how they fared in my own tests. They're customisable right down to the colour of the lid, bottle and style of straw. There was a menu of 17 bottle colours at the time of writing, from pretty pastels to utilitarian navy and khaki.
The bottle I tested had a flip-straw lid, but there are five lid options to choose from. You can open the flip-straw lid with one hand, with the spout flicking open for you to sip from. It also comes with a flexible carry handle that's big enough to be useful, plus impressive triple-walled insulation.
Why we love it
It's perhaps superficial, but I found the colours on offer appealing. My mint-green water bottle is easy to spot in my Mary Poppins-style tote bag without looking garish. And, during its time in residence at the bottom of said bag, I was pleased to find it didn't leak a drop. The bottle also performed well in my drop test, looking as good as new despite plummeting on to a hard floor from a height.
The mechanism on the flip-straw lid is smooth, even after several washes. Frank Green lines its water bottles with a ceramic coating, which it claims prevents that weird metal-tainted water taste you sometimes get. It's hard to test this against rivals, but I never noticed a metallic taste. The straw inside is made from metal, which felt more durable – I'm all for less plastic in general.
It's a shame that … even the smallest (595ml) bottle becomes heavy when filled, perhaps because of the heavy-duty insulation.
Dishwasher safe: lid, yes; bottle body, noBPA free: yesSizes: 595ml, 1l and 2lWeight empty (595ml): 340g
Weight filled (595ml): 870g
Yeti specialises in heavy-duty apparel, and no one needs a heavy-duty water bottle more than kids – specifically my kids. Everything about this insulated water bottle is robust, from the (slightly stiff) screw-on lid to the large, tactile carry handle. And adding to the utility feel, the bottle's opening is wide – great for jamming in loads of ice, if you want.
The double-walled insulation kept my kids' drinks icy for about three hours, even on hot days. The Rambler Jr comes in nine bright colours, which will make it easy to spot in the classroom.
Why we love it
One of the most important tests for kids' water bottles, if you ask me, is the leak test. Too many times I've seen my kids' reading books end up in a pool of water in their bags. Thankfully, the Yeti Rambler Jr passed this test.
It's easy to open one-handed, even for younger hands with less developed fine-motor skills. A rigid straw flicks up when you exert pressure on the tab. And this spout survived my kids knocking it around on the playing field at school, and didn't seem to suffer any bite marks either.
I liked that this bottle comes with two straws; it's always nice to have a spare. And, as a time-poor parent, I was happy to find that the whole thing washes well in the dishwasher.
It's a shame that … there isn't a wider selection of designs.
Dishwasher safe: yesBPA free: yesSizes: 355mlWeight empty: 500g
Weight filled: 855g
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As far as reusable water bottles go, Ocean Bottle goes above and beyond in terms of sustainability. It's a certified B Corp, and makes impressive pledges with every bottle you buy.
As well as its eco credentials, I loved using the Ocean Bottle Go. It's lightweight, has a flip-lid cap and a silicone straw inside. These bottles come in a range of shades and have a coating on the outside to stop them slipping through your fingers.
Why we love it
The Ocean Bottle Go is brilliant for use on the go. It's lightweight and small enough to slip into most bags, while the anti-slip coating means it doesn't become slippery even when wet.
It's insulated as well, and kept the ice in my drink icy for almost 90 minutes – and pleasingly cold for a lot longer. This bottle passed my leak test with flying colours, too.
As well as this, Ocean Bottle says revenue from each bottle sold funds the collection of 11.4kg of plastic – the equivalent of 1,000 plastic bottles – that would otherwise be bound for the ocean.
Using near-field communication and an app on your phone, you can track how many times you've refilled your bottle. From here, you can monitor your hydration, and if you're using an iPhone, it will also transfer this info to your Health app – although you can switch this off. Each time you log a refill in the app, Ocean Bottle funds the collection of an additional five ocean-bound plastic bottles. You can see your 'impact progress' in the app.
I found this feature a faff, as you have to wave your bottle near your phone every time you refill, but I loved seeing my hydration and impact clocking up.
It's a shame that … for the price, the capacity isn't larger (Ocean Bottle does offer larger sizes of its Original bottle, though).
Dishwasher safe: yesBPA free: yesSizes: 500mlWeight empty: 287g
Weight filled: 752g
Best for: hydration obsessives
I first learned about hydrogen water bottles this year, and I was a sceptic. I mean, look at the price tag – are people really paying that for a water bottle? Then I got the Echo Flask in for review, and was converted.
You plug your water bottle into the wall (I know, but stick with me here …) and charge it up. You then use the touchscreen on the water bottle to start a 10-minute cycle of releasing hydrogen into the water inside.
There is a school of thought that introducing more hydrogen into your water reduces oxidative stress, improves your athletic performance and shortens recovery time. Some studies have been done to prove this theory, including one on rats. The jury remains out on exactly how amazing hydrogen water is for humans.
It's impossible to test these claims as I am just one person without access to a lab, but here's my anecdotal experience: I drank from this water bottle every morning and noticed I didn't get dehydration headaches, and never suffered a hangover.
As you may expect for the price, the bottle pairs with a smartphone via Bluetooth and gives you lots of data to keep you motivated, if that's your thing. This includes how many 'flasks' you've consumed v the goals you've set, the length of your goal-meeting streak, and how much water and hydrogen you've consumed. It will also send you reminders on your phone for you to drink, should you forget.
It didn't make the final cut because … the price made me balk. And the lid leaked during testing.
Dishwasher safe: No, but it mostly cleans itself. There's a self-clean cycle you can select onscreen – for a deep clean, add a drop of white wine vinegar to the clean cycle.BPA free: yesSizes: 12oz (350ml)Weight empty: 487g
Weight filled: 793g
Best for: drinking on the go
The beauty of this bottle is its simplicity. There's no Bluetooth connectivity or dual spouts here. So, if your water-bottle preference is free pour rather than straw, Chilly's Series 2 is a great option.
It's well made and durable. The spout is curved to prevent spillages when on the move or in a rush, and I found it comfortable to drink from. It's easy to clean, too.
The metal bottle is double-wall insulated, and it kept my drink cold for hours. I liked the rubber base, which gave it a soft landing and protected it from bumps. A simple carry strap can be used, which I found useful (often on water bottles, I've found the straps superfluous to my needs).
It didn't make the final cut because … it's pricey for a simple water bottle.
Dishwasher safe: noBPA free: yesSizes: 350ml, 500ml, 1lWeight empty (500ml): 302g
Weight filled (500ml): 805g
Best for: those who hate water
Mark my words, this water bottle (which has enjoyed premium status in tweens' lives for a good few years) is for kids more than adults. The idea is that you attach a scented ring-shaped plastic pod around the straw, and your mind is tricked into thinking the water is flavoured as you sip.
I'm not convinced by this functionality. It works for a sip or two, but then my brain quickly realises it's being tricked. However, my kids loved the concept and all the many child-friendly flavours the pods come in. All the scents are made from natural flavours extracted from fruits, spices and herbs. It's worth bearing in mind that the pods need replacing when they lose their scent, and they cost from £4.99 for a pack of three.
I liked that the lid stays attached on the Click – previous versions didn't offer this. Now kids can't lose the lids in the school playground. Honestly, anything that gets my kids to drink water at this point is a win.
It didn't make the final cut because … it didn't pass the leak test.
Dishwasher safe: yesBPA free: yesSizes: 600mlWeight empty: 170g
Weight filled: 770g
Best for: working from home
When staying hydrated crosses over into a personality trait, many people – particularly gen Z – seem to reach for a Stanley Quencher. Make no mistake, the Quencher is a style statement. It comes in an array of shades and limited editions with cutesy names such as 'hydrangea' and 'dried pine'.
The 1.8l bottle I tested is enormous – my heart sank when I had to take it out of the house, despite the massive handle on it. It honestly took me back to the days when I used to carry a toddler on my hip, such is the size and weight. However, at home I was deeply into the Quencher. I found it brilliant during the working day as I didn't have to refill it as often.
There are three positions for the lid – covered, straw or sip. I tended to opt for the straw, but it's not leakproof, so if you're on the go, you'll have to make do without it. Stanley says it keeps drinks cold for 12 hours – but I noticed my drink slightly warming after about four hours in my tests.
It didn't make the cut because … it's impractically big, and therefore lacks the versatility of other bottles on this list (but it does fit car cup holders).
Dishwasher safe: yesBPA free: yesSizes: 590ml, 890ml, 1.18lWeight empty (1.18l): 658g
Weight filled (1.18l): 1.8kg
The key features are capacity and lid or spout style; make sure these fit your preferences and lifestyle. If you'll be taking your water bottle out with you a lot, you'll need to balance capacity against how heavy it is. You'll also want something that's reliably leak-free – look at the lid design and check the seals.
Insulation is worth considering. Having used an insulated water bottle, I could never go back. Why suffer tepid water if you don't have to?
Most insulated water bottles are made from metal, which means they're typically recyclable, durable and, importantly, BPA free. BPA (bisphenol A) is a synthetic chemical used in some rigid plastic food containers, and repeated exposure may cause health problems. Always look for BPA-free water bottles – all the ones on this list are.
Take your time to find a water bottle you love, and you shouldn't be tempted to replace it; this will not only serve you well, but the environment too. Ideally, you should opt for sustainable water bottles that are made from recycled materials and designed for long-term use.
Regular cleaning helps prevent bacteria and mould from building up in your water bottle. To keep your bottle hygienic, you should clean it properly at least once a day.
That means taking it apart and giving it a good wash in warm, soapy water – a quick rinse under the tap won't cut it. Soak your bottle for 10 minutes, then rinse with more hot water. It's best to let it air dry rather than drying it by hand. Stick to environmentally friendly washing-up liquid if you're keen to reduce your environmental impact. If your bottle is dishwasher safe, you can pop it in there instead.
Reusable water bottles are undeniably better for the environment when compared with their single-use plastic counterparts. In the UK alone, an estimated 35.8m plastic bottles are used every day, and just 55% are recycled.
Producing a reusable bottle requires more energy upfront, but that impact is offset over time. The key is repeated use: an MIT study estimates that a reusable bottle needs to be used between 10 and 20 times to break even with the carbon footprint of a single-use bottle.
The more durable the bottle, the better. A water bottle that has a fully stainless-steel body is best, despite the carbon footprint involved in producing it. Stainless steel lasts longer, has a lower impact over its lifetime, and is easier to recycle at the end of its life than plastic alternatives.
Zoë Phillimore is a journalist with 20 years of experience. She's tested many things, from mattresses to makeup, and she's slightly obsessed with finding small new businesses to spotlight. Aside from this, Zoë loves travel, being outside – especially on the beach – and finding screen-free things to keep her three very active children busy, as well as sharing her finds on her social media accounts