Insulated flasks all work in the same way, using a vacuum double-wall design to create a thermal layer. But they vary in terms of size, efficiency, and weight.
For hiking, you want the lightest possible option. But bigger, bulkier models can keep liquids hotter or colder for much longer. We've curated our top-rated insulated drinks flasks to help you choose the right one for your next trek.
The best insulated drinks flasks
Best insulated flask
An insulated flask should prioritise the job of insulating, in our opinion. Weight saving comes
- Several volumes available
- Very tough plastic parts
- Wide and narrow drinking
This vacuum insulated bottle will keep drinks cool for 24 hours. Combined with its convenient sip
- Wide and narrow mouth options
- Magnetic attachment for cap
- Good value
- Other have better insulation
Best flask for day walks
If all you need is something in which to carry a single serving of hot drink – be that a mug of
- Stanley tough
- Leakproof mug
- Smaller volume than others here
Best for two
When tea for two is on the cards, this is the perfect solution. Cleverly storing two cups in its
- Ideal for two people
- Includes two cups
- Not too heavy for its size
- Stanley Master Unbreakable Thermal Bottle has better insulation
Brimming with nostalgia – a Thermos just like your granny used to have – the retro Revival (also
- Memory lane looks
- Still durable
- Pretty good insulation
- Only one volume size
Camelbak's Chut Mag bottles come in insulated and non-insulated varieties, many colours, and
- Relatively lightweight
- Clever magnetic top
- Many volumes and colours
- Others have better insulation performance
This flask will keep your sauvignon blanc chilled or your mulled merlot hot for hours. It's
- Great for celebrating a tough hike
- Goes nicely with Hydroflask Wine Tumber
- Doesn't retain flavours of previous contents
- Hardly essential
Best for toughness
A proper traditional beefy flask that, unlike traditional flasks, is almost unbreakable. Big and
- Excellent insulation
- Heavy and bulky
What to look for in an insulated flask
Volume: Do you need something to keep a takeaway latte warm, or do you want a day’s worth of cuppas in your pack? Is it just for you, or will you be sharing the contents? These factors, along with how much weight you’re prepared to carry, will decide the volume of liquid you need to fit in your flask.
Weight: Remember, one litre of water weighs one kilogram. A flask will only get heavier when full, so consider the empty weight of the flask and its volume to avoid overburdening yourself.
Drinking method: Some flasks come with a separate cup, while others are intended to be drunk from directly. The latter of these may have different openings, and some will be better suited to cold drinks than hot, lest you risk burning your lips.
Robustness: Most modern flasks are less breakable than the traditional glass insulated models, but some are better than others. If you tend to chuck your pack around with gay abandon, it’s worth making sure you choose a tough one.
Level of insulation: Good insulation comes at a price, both in terms of actual cost and weight. Cheaper, lighter flasks may keep the contents warm for a few hours. But if you want your last sip of the day to be as hot as the first, you may have to spend a little more and tolerate the extra grams.