The need for caffeine in the world of work cannot be understated.
Indeed, I write this on my second cup of steaming hot Joe this morning, and that's before the clock has even struck 11am.
We’re not saying it’s particularly healthy that such a substantial proportion of the workforce needs a shot or two of piping-hot liquid gold every morning, but it’s certainly something to ponder.
Of course, some enjoy coffee in a slightly healthier, more artisan manner. We’re talking about the folks who enjoy the occasional cuppa as a treat, alongside a sweet bite like a cronut, or a cruffin – or some other strange pastry hybrid sensation.
Hot coffee and tea can also warm you up from the inside out whether you're commuting or flinging yourself around in the name of sport in horrible weather.. Like TikToker Ben Kielesinski, who always enjoys a cup of coffee with a view somewhere in the Canadian wilderness. How we’d like to be him.
No matter how you consume your hot drink of choice – be it coffee, herbal tea, hot chocolate or even soup – chances are you’d like that drink to remain hot wherever you’re sipping it. In fact, 90 per cent of the reason that I’m already two cups of caffeine down, is because my first serving cooled far too quickly.
The answer to all our collective, rapidly cooling hot drink woes? A vacuum-insulated flask.
What is a vacuum-insulated flask and how does it work?
Think of a vacuum flask as a cup within a cup. The space between the two vessels is evacuated of any air, creating a partial vacuum. This reduces the ability for heat to be conducted away, and it is therefore retained within the innermost vessel.
In your search for the perfect vacuum insulated flask, you might have also seen the gadget referred to simply as a ‘thermos’. The contraption soared in popularity after the eponymous American brand launched the very first Thermos product in 1904, after its founders domesticated the vacuum insulated technology which had been pioneered by Scottish scientist Sir James Dewar in 1892. As such, the term for a hot water flask has become synonymous with Thermos.
Best vacuum insulated flasks at a glance
- Best for a lifetime guarantee: Stanley Classic Legendary Bottle - £43.17, Amazon
- Best for saving the planet: Ocean Bottle x Wild Nutrition - £40, Wild Nutrition
- Best for good looks: Hydro Flask (355ml) Coffee with Flex Sip Lid - £28.95, Amazon
- Best for a tried-and-true classic: Thermos 470ml Stainless Steel Flask – Red - £21.59, Robert Dyas
- Best for a hi-tech, yet value for money option: Homealexa Vacuum Insulating Travel Mug - £11.99, Amazon
- Best for extra warmth and protection: Thermos Ultimate Flask 900ML / 900ML Pouch Set - £40, Thermos
- Best for tea lovers: Sigg Tea Set Small White - £42.38, Sigg
- Best for a long coffee break with a pal: Thermos Mondial Flask - 1.8L - £18, Argos
- Best forlong-term temperature maintenance: S’well Stainless Steel Traveler - £27.44, Amazon
- Best for an integrated French Press: GSI Outdoors Microlite Commuter Java Press - £37, Ordnance Survey
- Best for fresh espresso on the go: Wacaco Minipresso NS Portable Espresso Machine - £55.90, Amazon
To help keep your drinks warm, we've rounded up the best vacuum-insulated thermos flasks below.Shop now
Stanley Classic Legendary Bottle
Best for: a lifetime guarantee
First and foremost, we thought it fitting to include the vintage-inspired flask that Ben Kielesinski uses in his many adventure TikToks. Named the ‘legendary classic’ for a reason, this durable and reliable flask is made from BPA-free stainless steel and equipped with double-walled vacuum insulation. Available in either a 1L or 1.9L capacity, we were instantly drawn to its attractive sage green hue.
It’ll keep your hot drinks hot, and your cold drinks cold, for a whopping 24 hours, and is also dishwasher safe. It’s a winner in our eyes.
Buy now £43.17, Amazon
Ocean Bottle x Wild Nutrition
Best for: saving the planet
Every time one of these insulated bottles is purchased, funding is provided for the collection of the equivalent of 1,000 bottles worth of plastic from the coastline. Available in a beautiful deep turquoise hue thanks to a limited-edition collaboration with Wild Nutrition, this bottle is made from stainless steel, recycled ocean-bound plastic, is vacuum insulated, and has an integrated cup with a dual-opening for easy refilling.
Buy now £40.00, Wild Nutrition
Hydro Flask (355ml) Coffee with Flex Sip Lid
Best for: good looks
A little shorter than your cult classic double-walled vacuum insulated Hydro Flask, this 354ml option is designed specifically for keeping your favourite hot drinks safe, secure and at the optimum drinking temperature. Equipped with a handy leak-proof, flex sip lid, this model – like all Hydro Flasks –is also made from BPA free materials and is dishwasher safe.
Buy now £28.95, Amazon
Thermos 470ml Stainless Steel Flask – Red
Best for: a tried-and-true classic
You simply can’t go wrong with purchasing an insulated flask from the one and only Thermos. This cherry red option keeps its contents hot for 18 hours, or cold for 24 hours. The integrated stainless steel serving cup keeps your beverage extra warm while you’re sipping away, and we’re big fans of the fact that you can pour hot drinks without removing the twist stopper—which further prevents any heat from escaping.
Buy now £21.59, Robert Dyas
Homealexa Vacuum Insulating Travel Mug
Best for: a hi-tech, yet value for money option
With almost 4,000 positive reviews for this hi-tech vacuum insulating flask, we simply couldn’t believe the bargain price. The integrated LED screen displays the real-time temperature of your beverage, which is especially helpful for the eager beavers who often burn their tongues after some risky guesswork regarding just how hot their drink actually is.
It’s powered by a high-performance lithium-ion battery which intelligently functions on low power at all times, which means you’ll only need to replace the battery – at the very least – every two years. It keeps drinks hot for six hours, and cold for five hours.
Buy now £11.99, Amazon
Thermos Ultimate Flask 900ML / 900ML Pouch Set
Best for: extra warmth and protection
Another option from the iconic Thermos brand, this 900ml flask and pouch set is perfect for keeping your hot drinks extra hot during lengthy outdoor excursions and camping trips. Unlike many stainless-steel flasks, this one is remains cool to the touch even with the hottest of contents inside, making it suitable for clipping right onto your belt with the handy carabiner clip which is attached to the included pouch.
Buy now £40.00, Thermos
Sigg Tea Set Small White
Best for: tea lovers
A sophisticated and sleek design for herbal tea lovers, this set comprises of a 500ml double-walled 18/8 stainless steel bottle and a 300ml travel mug made from the very same materials. Designed and engineered in Sweden, both products are additionally equipped with a copper plating on the inside, which aids in insulation and also prevents the vessels from being hot to the touch.
Buy now £42.38, Sigg
Thermos Mondial Flask - 1.8L
Best for: a long coffee break with a pal
Stay caffeinated through all manner of outdoor adventures with this nifty portable flask which comes with two cups so you can share with the friend you like the most. It can hold nearly two litres which should be enough for eight rounds of coffee, tea or whatever beverage takes your fancy. Stays hot for 12 hours and cold for 24.
Buy now £18.00, Argos
S’well Stainless Steel Traveler
Best for: long-term temperature maintenance
Short and stout, this 470ml insulated bottle works equally as well at keeping the temperature just right for hot drinks as well as cold. In fact, get this: S’well claims the triple-layer of insulation and vacuum seal will keep drinks chilled for 24 hours, and hot for 12 hours. Impressive, any way you slice it.
Buy now £27.44, Amazon
Insulated flasks with integrated coffee makers
GSI Outdoors Microlite Commuter Java Press
Best for: an integrated French Press
Though at first glance this product looks just like your standard insulated flask, what sets the Microlite Commuter Java Press from the others is hinted at in the name. It’s got a hidden, integrated French press for making the freshest coffees on the go, no matter where you are. Granted, you’ll still need to add hot water to coffee grounds either at home before your excursion, or using a portable kettle and stove while you’re out camping. Once that’s done, simply re-insert and push down the
Buy now £37.00, Ordnance Survey
Wacaco Minipresso NS Portable Espresso Machine
This funky, Nespresso pod compatible device provides extra-hot, fresh espresso without the need for electricity. Nope, we couldn’t believe it either.
Simply pop your pod in, and manually crank the semi-automatic piston. The device has an integrated, insulated hot water compartment which feeds piping hot liquid through the pod filter to create a fresh full-bodied espresso.
However, you can also purchase an extra-large Minipresso tank via Amazon to create longer coffees which require more hot water, such as Americanos.
Buy now £55.90, Amazon