Looking for the best sleeping bag to keep you warm when you wild camp?

Who knows what I used as a teenager, probably something I found at home but I started proper wild camping in the mountains with a Vango synthetic sleeping bag that I’d used with the family on campsites, I imagine most people do.


This green synthetic sleeping bag was huge, took half of my 60l rucksack up! It was just about warm enough.

The first thing you’ve got to know about sleeping bags is that THEY do not warm you up. YOU warm you up. The sleeping bag is simply an insulator, it reduces the loss of heat from your body into the environment. It does this by trapping a layer of air in the fibres.

Synthetic bags are a man-made material, plastic basically, they take up twice the space generally than the other type of insulation, down. Down is found under the feathers of birds. Goose down is used in good quality sleeping bags. Because it’s so fluffy and fine, the warmth to weight ratio is higher than that of synthetic material. In mid-ranged bags, however, you’ll find duck down. So, there are two main materials used, synthetic and down.

I’m not going to test anything, I’m not even going to compare numbers. Over the years that’s what I’ve done many times and I’m simply going to offer you my opinion on what I’ve learned and felt out there in snowstorms, sometimes admittedly freezing all night. One that comes to mind was caused by condensation in the tent, a bivvy bag would have stopped that.

Winter wild camping
Winter wild camping

Sleeping bags are not as different as the tickets say. The most important thing to look at on a sleeping bag that you want to keep you warm on freezing nights is the EN13537 Comfort rating. This should be below zero to be comfortable in the Winter and if you need the bag for arctic conditions then you know as much or more than I do already (see link at the bottom of the page).

So, synthetic takes up twice the space and down is half the weight. It’s a no-brainer, choose down. Which brand? Well, there are many and they do offer different design benefits BUT unless you have £500 in the budget or you’re off to Everest then the bespoke companies are out of your league. You’ll pay them an extra few hundred to make the bag a bit more to your spec. This is fine. but for most of us, the budget may only stretch to say £200.

The WeeNest on Redmond's Edge
The WeeNest on Redmond’s Edge

Best Budget Down Sleeping Bags

For me, £200 is best spent with Alpkit. I had a SkyeHigh 1000 which had an EN comfort rating (the important number) of -2 but I’ve gone to sleep at 8 pm and it was -10c outside, been comfortable throughout the night and woke to find a snowstorm had frozen the tent. I measured 30c in the bag!

Since selling that on, I now own a SkyeHigh 500 for summer and have used a 900 for winter until just recently when I splashed out on a more expensive but lighter bag (more later).

Get your Alpkit sleeping bag here:

I have no affiliation with AlpKit, they just sell great stuff!

The Skyehigh 1000 was always too hot in the coldest of summer UK nights for me so I end up sweating, which will cause discomfort and by the time you get up, make you cold.

Awesome Sleeping Bags For Winter

So, now that I’m hell-bent on ‘going super ultralight I invested in a new sleeping bag. It’s a down bag, but it’s the best quality diamond grade 850 FP Polish goose down. Polish geese don’t migrate in the winter. What that means is that they are conditioned to withstand the Polish winter and so grow better down under their feathers. Canadian geese migrate to warmer climates, it’s TOO cold in Canada, so they don’t develop the finer down.

Criterion Quantum 450 Features
Criterion Quantum 450 Features

Weighing in at 850 grams, with a comfort rating (tested at Leeds University) of -10c, my new sleeping bag helps me get my pack base weight down below 3kg! I’ve learned that it’s not just the weight of the material and the quality of the down that gives you a light but very insulating bag.

See, the construction of the layers in the bag makes a big enough difference to give you another degree or two on the rating. Criterion sleeping bags are made using a trapezoid construction so the weakest parts (thermally) are not so close to each other. A good example of poor construction thermally would be the down coat I’ve been wearing for three years – it’s just ‘stitched through’ which means there are cold spots EVERYWHERE. And to make a stitched through coat more thermally successful they use more down which costs more and weighs more!

Criterion Quantum 450

Criterion Quantum 450 Goose Down Sleeping Bag

I now use the Criterion Quantum 450 sleeping bag for winter. Here are some key features:

  • Comfort Rating -10c
  • Weight: 850 grams
  • Price: £369
  • Packs to 150 x 150 x 300mm

I sleep cold and I camp under a tarp so I’m not going to kid myself that I would be comfortable at -10c without taking some other precautions.

Sleeping in a dry base layer is always a good idea. The moisture in damp clothes can really suck the heat out of you. You just feel so much more comfortable. I would really recommend using a sleeping bag liner as well. Not only does it keep your sleeping bag cleaner, meaning fewer washes in its lifetime, but they say you get another degree out of your sleeping bag.


I’ve tried to keep this short and easy to understand for the less experienced campers out there.

Don’t fall for all the technically confusing jargon. If you’re not bothered about the weight or size, you’re free to go with a synthetic sleeping bag but if either of those are going to be an issue, you need a down bag. If you can afford up to £200 then in my opinion…

When you have a bigger budget or you are travelling to colder climates I would really recommend a Criterion sleeping bag. They make a sleeping bag that has a Leeds Comfort Rating of -40c!

Feel free to comment mentioning what keeps YOU warm in Winter but please include the comfort rating for comparison.