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The best thermos flasks 2022

Handy, reliable and eco-friendly, a thermal flask is the perfect companion on your daily commute, walk or hike. Keep your coffee hot all day long with these trusty flasks that Mumsnetters swear by.

By Mumsnet HQ | Last updated Jun 1, 2021

Selection of flasks

Want something reliable to carry your drinks on-the-go? Here are the best thermos flasks to buy in 2021.

1. Stanley Classic Vacuum 1L Bottle

Stanley flask

A thermos flask that keeps drinks hot or cold for 24 hours – does it get much better? The Stanley brand has been around since 1913 so they’ve certainly been through their fair share of research and development over the years. Fast forward to today and you can expect your drinks to stay at the temperature you need, for as long as you need, whether you’re at home, work, camping or backpacking. Mumsnetters like the heavy-duty Stanley flasks because they’re extremely hard-wearing, 100% leak safe, non-toxic and won’t leave that nasty metallic taste in your mouth. Plus, if you’re not completely satisfied, they offer a money back guarantee – that’s confidence for you.

“I highly recommend Stanley thermos flasks. From my experience, other thermos flasks may look good but just don't seem to keep drinks hot enough, which isn’t very efficient.”

2. Klean Kanteen Stainless 20oz Flask

Klean Kanteen flask

If you’re after a thermos that’s as functional as it is stylish, this one from Klean Kanteen could be for you. It features a food grade 18/8 stainless steel construction, double-walled vacuum insulation and keeps its contents hot for up to 20 hours or, if you’re in hotter weather, keeps drinks iced for up to 50 hours. Thanks to its larger opening, you can fit ice in easily and fill it up without any hassle. Pick from five colours and away you go.

“I'd definitely go for a Klean Kanteen thermos. Their insulated flasks keep hot drinks hot for HOURS. On more than one occasion I've made coffee in the morning and forgotten about it, only to discover it again after 4pm and found that it's still hot.”

3. Contigo Travel Mug 470ml

Contigo flask

For people who have an active lifestyle and are on the go a lot, Mumsnetters recommend trying this Contigo travel mug. While it may not stay hot for as long as other brands (expect hot drinks to last around five hours), it has been specifically designed for one-handed drinking. So if you have a long commute or you’re travelling via car, bike, train or plane, all you have to do is press a button and sip away. It comes in eight different colours, is completely spill-proof and there’s no fiddly lid to remove while you’re battling the crowds or rushing around the shops. Convenience on the go – sometimes that’s exactly what you need.

“Get a Contigo travel cup. They are absolutely water-tight and fully meal-proof. Even though they’re not cheap, they are worth every penny.”

“I recommend Contigo too. I throw my flask in my handbag every morning and there are never any leaks – I’ve even accidently thrown it across a car park and it still works.”

4. S’well Unisex Travel Mug 470ml

S'well travel flask

If you’re looking at giving a flask as a gift or you’re all about cute prints and fashion-forward style, you’ll love these travel mugs by S’well. They come in just about every shade or print imaginable and can be purchased in various sizes from 350ml to 590ml. Aside from a pretty aesthetic, S’well flasks keep food and drinks hot for up to 12 hours and are considered a must-have accessory for city commuters. Scrap people watching and try S’well watching instead – you’ve probably already come across them on more than one occasion. If you can’t beat them, join them.

“S’well flasks are great. I take coffee in mine everyday and put it right next to my laptop – it never leaks.”

5. Camelbak Insulated Travel Mug 473ml

Camelbak flask

Much like the brand’s water bottles, Camelbak travel mugs are firm favourites among Mumsnetters. They’re leak-proof, available in a spectrum of bright colours and are great for one-handed drinking so you can hike, climb and run as much as you like yet still enjoy a comforting sip of coffee or tea when you have a moment to spare.

“Camelbak travel mugs are excellent. They can be a bit pricey but mine is still going strong after more than 9 years so I’d say they are definitely worth the investment.”

6. Tefal Travel Mug 0.36L

Tefal flask

For a flask that feels more like a mug, try this one from Tefal. It keeps beverages hot for up to four hours and features a soft-touch silicone wrap for added comfort and a secure hold. You can even drink from all sides of the lid thanks to its 360° mouth design. Gone are the days of burning your hands on the surface or triple checking that you’re not about to miss your mouth. Easy, comfortable to hold and affordable. Job done.

“I have a Tefal coffee mug and I can safely say that it is leak-proof (it often travels in my bag and hasn’t once leaked). It keeps coffee hot for hours too.”

7. Frank Green Reusable Cups

Frank Green flasks

They may resemble portable speakers but Mumsnetters can’t get enough of Frank Green’s reusable cups. Their innovative design is available in three sizes; 175ml, 295ml and 475ml so you can easily pick the capacity that suits your lifestyle or distribute them among your family as handy gifts. First you pick which type of cup you prefer (stainless steel or fully recyclable co-polymer), then you pick the size and colour – personalise it as much as you like by selecting separate lid, button and base colours.

“Mine is from Frank Green. I’ve never had anything so awesome! It keeps beverages warm, it’s leak proof and it even goes in the dishwasher. You can customise it too – mine is pink and grey.”

8. Thermos Ultimate Series Flask 900ml

Thermos flask

8. Thermos Ultimate Series Flask 900ml

Outdoorsy types really like the Thermos Ultimate MKII Series Flasks. They feature a sleek, lightweight design, a shock-absorbing silicone ring and unique heat performance technology so even if you drop it, the flask and its contents will stay intact. Highly durable and uber hardworking, this series could be the perfect fit if you’re in the market for a flask that is more traditional and less ‘trendy’.

“I have the Thermos Ultimate Series Flask, it lasts me all day and keeps food very hot! The official rating from Thermos says it keeps things hot for 24 hours – that’s more than enough for anyone!”

Prices correct at time of publication.