Top 7 best Thermos flasks for UK hiking

Our selection of the very best Thermos flasks for your UK hiking trips. Everything from beverage flasks to food flasks – check out the top options listed below. 

Best Thermos for UK Hiking

A good hike is always made better with a hot brew. Packing a Thermos flask in your rucksack is a sure-fire way to warm your cockles and keep spirits high, so it’s important to choose a good one. There are plenty of flask options out there to keep your food and drink warm, but the very best will ensure a steaming hot treat every time you head out into the hills.

To make sure you’ve always got a hot cup of tea, coffee, or soup at the summit, we’ve assembled a list of the very best Thermos flasks available in the UK in 2022 right here.

Author’s top pick

Thermos Ultimate Series Flask

Best Thermos flask for hiking – Ultimate Series 500ml

What is a Thermos flask?

First, it’s important to get the small print of this article out of the way. Thermos is a specific flask brand – the first to create commercial products using vacuum insulation technology in the early 1900s. The name Thermos is actually derived from the Greek word for heat –  Thérmé. 

Thermos uses technology originally discovered by Scottish scientist Sir James Dewar in 1892. These flasks are made up of both a durable interior and exterior with an insulating air pocket of sorts running through the middle. While traditional containers lose heat through the process of convection, the airless space between a Thermos flask prevents this from happening.

This article will specifically cover Thermos flasks available on Amazon, but if you’d like other brand options, we have a separate article on the way.

Things to look for when buying a Thermos flask

There are thousands of Thermos flasks on the market right now, so knowing exactly what to buy can be difficult. Fortunately, there are a few key factors that can help you to decipher your individual needs and make the decision much easier.

Consumption method

What are you planning to store in your flask? Do you want to enjoy the odd coffee at the top of a hill, or are you hoping to carry foods like pasta and soup? Traditional flasks generally come with a lid that doubles up as a mug, while Thermos bottles are created for you to drink from directly.

If you’re planning to eat from your flask, however, it is definitely best to purchase a larger, wider container. These Thermos flasks often come with a lid that’s large enough to be used as a bowl, and some even have their own folding forks and spoons. 


Are you a solo hiker, or do you prefer to walk in a group? If you’re the latter, it’s likely your friends and family are going to want to get in on the flask action, and you’ll end up sharing your cuppa when your pals are caught short. 

Consider this when shopping for your Thermos – do you want a good 500ml container, or are you going to need something a little larger for sharing?


Adding a flask to your hiking essentials can quickly increase the weight of your backpack. One litre of water is equivalent to one kilogram of weight, so buying a lighter flask is the best way to save your back (and legs!) when out on your adventures. 

A good quality, lightweight flask can weigh in from around 0.35kg – this is a great base figure to keep in mind when shopping for your container. 

Insulation level

How long do you need the contents of your Thermos flask to stay warm? More expensive flasks tend to keep food and drink hotter for longer, but this may be of little use to you if your coffee is likely to be gone within the first hour of your hike. On the flip side, purchasing a cheaper flask is no good if you’re planning to store its contents for most of the day. 

All insulated flasks are made up of both an interior and exterior container, with a cavity separating the two. Though most commonly used to keep hot food and drink warm, they can also be used to keep cold drinks cool. It’s usually the quality and opening of a flask that determines how well it performs in each situation – most brands list an insulation timeframe which will give you a get idea of the quality of the Thermos.


If you know your rucksack is no stranger to a little rough and tumble, it’s probably best to purchase a stronger, more durable Thermos flask. 

The inner container of older and cheaper flasks are more likely to crack if dropped, so investing in a stronger option is likely to work out much better in the long run.

Best Thermos flasks for hiking by category

Reading in a hurry? Check out our top recommendations for different types of crampons in the bulleted list below:

  • Overall best Thermos flask – Ultimate Series Flask (
  • Top budget Thermos flask Light Compact Flask (
  • Best Thermos for solo hikers – Stainless Steel King (
  • Best Thermos for kids – FUNtainers (
  • Best Thermos for food – 470 Plus 590ml Dual Compartment (
  • Best budget food Thermos – Stainless Steel King Food (
  • Best Thermos flask for coffee – Thermos Travel Tumbler (

1. Ultimate Series Thermos

Purchasing a one-size-fits-all flask that meets your every need can be difficult – until now, that is. The Ultimate is a great Thermos flask for hiking, climbing, biking, and more. Created with maximum heat performance in mind, this flask keeps hot for 24 hours and cold for 24 hours.

It’s also super durable, so perfect for outdoor adventurers. Built with both a stainless steel interior and exterior, the Ultimate also uses protective silicone rings to buffer the container if you were to ever drop it. 

This flask is available in both 900ml and 500ml options. We’d recommend the larger of the two if you’re travelling in a group – especially as it weighs in at just 0.4kg. Standing at just under 30cm tall, you will be able to slot this Thermos flask into the water bottle pocket of most backpacks, or even just pop it into the main pocket – it’s guaranteed not to leak. If you want the very best Thermos flask out there, this is definitely the best option for you.

Best overall Thermos flask – Thermos Ultimate Series

The Thermos Ultimate Series is one of the most robust flasks available for hikers, keeping hot or cold drinks at temperature for 24 hours. 

Thermos Ultimate Series Flask
  • Keeps hot drinks for 24 hours
  • Keeps cold drinks for 24 hours
  • Two-part stopper
  • Protective silicone rings for increased durability

2. Light and Compact Thermos flask 

If you’re looking for unbeatable Thermos quality at a price that’s easier on the bank balance, the Light and Compact Flask is a good shout. This container will keep hot for 14 hours, and cold for 24 hours. Though this doesn’t have the heat longevity of the Ultimate Series, it’s still likely to be more than long enough for the majority of adventures. 

Suitable for one or two-person use, this flask has a 350ml capacity and weighs in at 0.31kg, making it perfect for weekend strollers or even daily commuters. If you’re someone who enjoys a coffee on your walks on a mug of soup with your lunchtime sandwich, this is definitely a good option. 

The Light and Compact has a push-button stopper for easy pouring into the lid of the thermos, which doubles up as a cup. This flask is available in two colourways – midnight blue and stainless steel. The latter of the two is the cheaper option and looks better too, in our humble opinion!

Best budget Thermos flask – Light and Compact Thermos

The Light and Compact flask is one of the cheapest all-rounders available at Thermos, offering the same great insulation specs at a pocket-friendly price. 

Thermos Light and Compact Stainless Steel Flask
  • Keeps hot drinks for 14 hours
  • Keeps cold drinks for 24 hours
  • One or two-person use
  • Push-button stopper for easy pouring

3. Thermos Stainless King Flask

This fantastic all-rounder from the stainless steel thermos range is a classic flask for every day, individual use. It’s a fantastic companion for all your adventures and is particularly great for hiking – keeping hot for 18 hours and cold for 24. 

The King is also available in a huge variety of colours, so there’s a flask to suit every personality. It’s easy to enjoy drinks in this container thanks to the insulated stainless steel serving cup, and the flask uses a Twist and Pour stopper so there’s no loose items to leave behind on the top of mountains. 

Enjoy 470ml of capacity with a base weight of just 0.37kg, perfect for adding your poison of choice – whether that’s tea, coffee, hot chocolate, or even soup. A timeless classic for the thermos flask fan. 

Best Thermos flask for individuals – Thermos Stainless King Flask

The perfect companion for all your solo adventures, the Stainless King has 470ml of capacity and is available in a full range of colours, so there’s always one to suit your style.

Thermos Stainless King Flask 1.2L
  • Keeps hot drinks for 24 hours
  • Keeps cold drinks for 24 hours
  • Insulated stainless steel serving cup
  • Twist and pour stopper

4. Stainless Steel FUNtainer

If your kids have seen the adults with their fancy thermos flasks, it’s likely they’re going to want to get in on the action. Thermos gives children independence with their very own 290ml FUNtainers, designed to keep food warm for 5 hours and cold for 9 hours. 

These lunchtime-ready flasks are made of BPA-free stainless steel which is cool to the touch. Their wide mouth means FUNtainers pretty easy to fill, eat from, and clean – making them a huge hit with parents, too!

Weighing in at 0.23kg, your little ones should find no issue in carrying their very own kid’s Thermos flask, and the Ergonomically designed lid will ensure no spillages or other mishaps. If you’re looking for a children’s drink flask, thermos sells these too – check out the brand’s FUNtainer Hydration Bottles.

Best Thermos flask for kids – Stainless Steel FUNtainer

Give your kids a sense of independence with their very own thermos flask, designed to be easy to fill, eat from, and clean.

Thermos Stainless Steel Food Flask
  • Keeps hot food for 5 hours
  • Keeps cold food for 9 hours
  • BPA-free stainless steel
  • Super lightweight

5. 470 Plus 590 Dual Compartment Flask 

This is an absolute beast – the Dual Compartment Thermos has to be the best flask for food. As the name suggests, this 1.1L flask is split into two compartments – one for hot food, and the other for cold. 

Hot food will keep to temperature for 7 hours in this Thermos, while cold food will keep for 22 hours. The stainless steel section will even maintain its heat when refrigerated, meaning you can have even more control over organising and storing your meals.

Carry the flask using the integrated handle, and tuck in with the full-sized folding spork attached to the container. This simple and adaptable food Thermos allows you to keep your lunch altogether, stored at the perfect temperature. 

Best Thermos flask for food – 470 Plus 590 Dual Compartment Flask

Keep your food stored together in one handy place with this beast of a food flask from Thermos.

Thermos 470 Plus 590 Stainless Steel Dual Compartment Food Flask
  • Keeps hot food for 7 hours
  • Keeps cold food for 22 hours
  • Two compartments to keep both hot and cold food
  • Attachable full-sized folding spork

6. Stainless King Food Flask

If you don’t need the bells and whistles of the Duo Compartment Flask, then a great cheaper option is the King Food Flask. This will also keep food warmer for longer than the option above – keeping heat for a full 9 hours. It is only designed to keep cold food at temperature for 14 hours, however, which is less than the compartment Thermos. 

Keep pasta, soup, and more in this flask without the worry of spillages or other mishaps. The insulated lid doubles up as a wide bowl, and it comes with an attached full-size folding spoon so you’ll never forget your cutlery!

This particular Thermos has a capacity of 470ml, but you can also purchase a larger, 1-litre container if you’re planning to share with others. The food flask also comes in a range of colours, which we all know is the important part – technical specifications aside.

Best budget food Thermos – Stainless King Food Flask

Keep it simple with this stainless steel food flask – use the lid as your bowl, grab the detachable spoon, and you’re good for lunch.

Thermos Stainless King Food Flask
  • Keeps hot food for 9 hours
  • Keeps cold food for 14 hours
  • Insulated lid, doubles up as a bowl
  • Full-sized folding spoon included

7. Stainless Travel Tumbler

The travel tumbler range at Thermos is a great place to find containers for your teas, coffees, and hot chocolates. These sleek individual-use travel mugs hold 470ml of liquid and come in six colourways to fit your every mood.

Keeping hot drinks for 7 hours, your coffee could literally last your full working day if you wanted it to. The tumbler can also keep cold drinks for 18 hours, perfect for sweltering offices through the summer months. 

Reviewers love this Thermos flask on Amazon for its stylish design, including a built-in tea hook that holds tea bags and more loose tea infusers. Plus, with the same 5-year guarantee attached to all Thermos products carry, you’ve got a travel mug for the long haul.

Best Thermos flask for coffee – Stainless Travel Tumbler

Enjoy your favourite hot or cold drink in this sleek and colourful travel tumbler, perfect for long commutes.

Thermos Stainless King Travel Tumbler
  • Keeps hot food for 9 hours
  • Keeps cold food for 14 hours
  • Insulated lid, doubles up as a bowl
  • Full-sized folding spoon included

Conclusion – what is the best Thermos flask for hiking?

Honestly, all of the Thermos flasks we’ve listed above would be great for hiking. Just assess your needs using our 5-part checklist at the top of this page, then select the best container for the job. We’ve listed flasks for food, coffee, families, and kids – so there’s sure to be something to fit your preferences. 

There’s also plenty of other options available at Thermos, check out the Thermos Amazon store to browse the full range with fast delivery.

FAQ: The best Thermos flask for hiking

Have a question about the Thermos flasks above that needs answering before your purchase? Take a look through our FAQ below and we’ll try our best to answer your query.

If you still haven’t managed to find the answers to the questions that you’re searching for, don’t hesitate to head over to our Facebook, Instagram or Twitter and reach out there. We’re always happy to chat about all things outdoors and we’ll even be able to offer personalised advice.

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