Much the same as packing the right clothing or boots, making sure that you’ve got a reliable way of keeping your favourite drinks warm is just as important when it comes to keeping the chill away. 

The popularity of flasks and bottles has soared in recent years as people look to shift away from single-use plastics – be that in regular water bottles or coffee cups – so that, today, there’s a good variety of choices out there. 

Plus, this added variety means more scope for personalisation than ever. So a flask needn’t be just a simple piece of kitchenware – it can also say a little bit about you. Here, we’ve rounded up some of the very best flasks on the market today. Plus, not only will they keep your drinks warm in winter, but they’ll double up to keep things chilled during summer. A win-win!

Stanley Legendary – from £44.99

For

• Classic appearance
• Plenty of capacity options
• Dishwasher safe

Against

• Heavier
• Only subdued colour options

Stanley has a rough-and-tough approach to its flasks. The Legendary flask, as you might expect, looks properly old-school, with a finish which feels similar to a newly-painted metal fence. 

But behind these classic looks, it’s got some really good specifications. Available in sizes ranging from thirst-quenching 750ml right the way through to a seriously-hydrating 1.9-litre, the Legendary promises the ability to keep hot drinks warm for 24 hours – and it’ll match that time when it comes to keeping cold drinks chilled, too. 

It’s got the added benefit of being dishwasher safe, so there’s no need to mess around with brushes and sponges at the end of the day. On larger capacity versions you also get the classic lid which doubles as a cup – particularly handy when you want to stop and enjoy your drink properly. 

Yeti Rambler – from £25

If there’s a company which has gone from strength to strength in recent years, it’s Yeti. Famed for its tough coolers, Yeti has also established a name for itself in the drinkwear segment. Its Rambler line-up – which covers both bottles and travel mugs – has got the same rock-solid build quality that we’ve come to expect from Yeti, while double-wall insulation means that they’ve got things covered in terms of heat retention too. 

Plus, the Rambler range has the added bonus of incorporating different types of caps and spouts that can be interchanged between the range. The chug cap, for instance, is a traditional open-mouth style but the ‘HotShot’ cap, in contrast, is more suited for when you’re drinking hot beverages on the go. 

The Rambler range does bring a weight penalty – particularly the larger-capacity bottles – but they feel nice and solid to use. It’s worth noting that there’s a bit of a trade-off between insulation and capacity – the Rambler does keep things very warm, but it’s not able to hold quite as much liquid as rivals as a result. 

For

• Solid construction
• Loads of colours to choose from
• Interchangeable caps

Against

• Heavy
• Some models might be too large for a car’s cupholders
• Capacity of some versions is down on rivals

SIGG Thermo Flask Gemstone – £36.99

Swiss outfit SIGG has been producing water bottles and flasks for a long while now, cementing itself a reputation for reliable and particularly sturdy products. The Thermo Flask is one of its key models and, like others here, it still uses that tried-and-tested double-wall insulation method.

However, the Gemstone collection of Thermo Flask differs through its copper coating inside which helps heat retention further, while a stainless steel exterior means it’ll be able to take sizeable drops and impacts. 

SIGG claims that the Thermo Flask is completely leakproof, but it cannot be cleaned in the dishwasher – this one is handwash only, too. However, a special type of construction means that the inside body of the Thermo Flask is thinner and therefore lighter. To feel, the Thermo Flask feels noticeably featherweight, in fact, yet it’s still got plenty of capacity inside. You can get it 500ml, 750ml and 1.1 litre sizes, too. 

Embossed lines help to make the flask’s construction even more solid and provide some handy grab points. However, the slightly slippery finish of the stainless steel exterior means that it could prove a little hard to keep hold of in the rain. 

For

• Really solid construction
• Surprisingly lightweight
• Good options in terms of capacity

Against

• Slippery exterior might be a pain in the wet
• Not dishwasher safe

Hydroflask – from £34.95

Hydroflask has a wide range of bottles to choose from. They come in a variety of different ‘mouth’ openings, too, and there’s the option to add a handy ‘flex straw cap’ which helps when drinking on the move or when you fancy using the bottle when exercising.

Hydroflasks says that its bottles should keep beverages hot for 12 hours – and cold drinks chilled for 24 hours – thanks to, you guessed it, a dual-wall construction. Thankfully BPA and toxin-free, Hydroflask’s bottles are also dishwasher safe which helps to make clean up a little easier at the end of the day. 

Each one comes with a flexible strap – similar to the Chilly’s – but it’s robust and reliable if you’re carrying the bottle from it or decide to lash it to a backpack. We’re also big fans of the Trail Series which, thanks to a different construction – including a perforated carry strap with aluminium pivots – to the ‘regular’ bottle, brings a 25 per cent weight saving which could really help when you’re trying to reduce bulkiness from a pack. 

For

• Solid construction
• Dishwasher safe
• Optional Trail Series helps to reduce weight

Against

• Not too many colour options
• Larger capacity versions with rounded design might be tricky to grip

What to look for in a thermal flask?

Keep-hot times

After all, keeping things hot is the name of the game here. So it’s worth comparing the ‘keep hot’ time that each flask is accompanied by. There’s quite a bit of variation, too, despite similar construction techniques. Of course, it depends on what you’ll be using the flask for – if you’re just taking it on simple day-hikes, then 12 hours of ‘keep hot’ will be more than enough. 

But if you’re doing an overnight camp and want to wake up to warm coffee in the morning, then you might want to look at a flask that’ll keep things hotter for longer. 

Dishwasher safe

Do you often get to the end of the day and run out of enthusiasm for cleaning up all of your kit? There’s definitely something appealing about being able to put your flask straight into the dishwasher – particularly if you’ve been having oaty or milky drinks in it. There’s no real drawback to having dishwasher-safe functionality, either. 

But likewise, most flask manufacturers do offer some kind of cleaning kit if you’d rather wash them by hand. Don’t want to buy a cleaning kit? Try a fresh toothbrush and some standard kitchen soap. 

Personalisation 

Personalisation is a big part of the flask business these days. You only need to look at Chilly’s, with its countless patterns and colour options, to see that making your flask ‘yours’ is a really popular thing. 

That said, if fancy colourways isn’t your thing then there are plenty of more traditional-looking bottles. 

Capacity

Capacity, capacity, capacity. As you’ll see from our list, you can get most flasks in a number of different capacities, so there’s always something to suit the kind of adventure you’re heading out on. But it’s worth remembering that most ‘large’ flasks do bring a weight penalty, so it’s a good idea to think about just how much you really need to carry with you. Short day hikes? Maybe a 500ml flask would do the trick. A few days on the trails? That one-litre flask might be better suited. 

If you do need that space but want a lighter option, then look out for flasks which have been designed to be as featherweight as possible. Hydroflask’s Trail Series, for example, is lighter without forsaking that keep-warm ability.