The Best Ultralight Sleeping Bags of 2021

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When going on a long hike, mountaineering, or kayaking through the Grand Canyon, there will be the inevitability of needing two things, food and sleep.

What this means to you is, you are going to have to pack a sleeping system, and part of that sleeping system is a sleeping bag. This post best ultralight sleeping bags is for those that want a a good bed and a light one so they can carry it with ease.

Best Ultralight Sleeping Bags

Types of sleeping bags

There are a couple of different styles of sleeping bags. You have your run-of-the-mill rectangular bags; these are good for car camping or trips where you the weight of the bag is not too big of a deal.

However, they are generally only recommended for sleeping in temperatures above freezing, and the ones that are rated for extreme temperatures are entire to heavy to dragging with you all through the mountain ranges you are hiking.

The other type of sleeping bag (and the one that we will be looking at today) is the mummy bag. These are excellent because the conforming nature of them allows your body to regulate temperatures. This is achieved by having it fit snugly around your body so that there is no excess air in the bag.

What makes a good mummy bag

When looking for a quality mummy sleeping bag, there are a few factors that you will want to take into consideration. First, it must be lightweight, the entire point of a mummy bag is so that you can retain heat without having to carry more weight than you need to. Second, it must top-notch warming capabilities.

Most times the entire reason you need a mummy bag is that you are going to spend some time in frigid environments. Let’s look at a few ultralight sleeping systems that I have found to be of excellent quality.

Sea to Summit Spark SP1

This sleeping bag is a great one for us to start off with and gives new meaning to the term “ultralight gear,” you will not believe how incredibly light this sleeping bag is. It comes with a lightweight “Ultra -sil” compression bag (great for cinching it down to the smallest size that physics will allow) and a mesh laundry bag.

The bag weight is only 12.3 ounces, so it is not going to slow you down while out on the trails. It also has 850 plus loft ultra-dry down, so it is capable of keeping in some heat, down is great for heat retention. And the shell is 10d nylon with the inner lining being 15d nylon.

By the way, the pack down size is unbelievable (I dare say your hiking buddies won’t even notice you brought a sleeping bag) cinching down to about 5” x 9”. I love how compact this sleeping bag is.

Should you get this

While this is an excellent product, it is only rated for 46-degree Fahrenheit, and above, this temperature range is usually considered a summer sleeping bag. If you are going to be doing some hiking during the more mild seasons, then this is good for you. But if you’re headed into freezing or below freezing temperatures, then stay away from this one.


The North Face Super Light 35F

This North Face sleeping bag allows you to trek a little bit deeper into the colder areas. It has a lower temperature rating for 32 degrees Fahrenheit, and its comfort range is around 41 degrees. This is another bag that has a much lighter weight than what you would expect for such a large bag, coming in at 1 pound 2 ounces.

Continuing with the specs of the product, it has a compressed volume of 236 cubic inches and a stuffed volume (the size it cinches down to) of 8” x 11”.

The 800 fill pro down repels water, and the bag also comes with the compression and carry sack. The partial draft collar and draft overlap keep heat from escaping your sleeping system, keeping you warm throughout the night.

Some features that I – personally – love are the center zipper, the inside pocket, and best of all the foot ventilation zipper. These are all very convenient features, and the foot zipper is great for nights that I stay relatively warm outside.

Should you get this

The North Face bag isn’t as small and compact as the Sea to Summit bag we reviewed earlier, but it is great for some of the colder environments that the Spark SP1 cannot comfortably take you to. If you are going to be trekking some cold conditions, while not being subjected to frigid temperatures, then this will be a purchase you enjoy for years to come.


Big Agnes Flume UL 30

Another extremely lightweight product that offers maximum warming protection, this is easily the warmest bag on the list for today. The bag weight is 1 pound 6 ounces for the regular size and 1 pound 8 ounces for the large.

It has 3-D anti snag draft tubes that keep heat from escaping out of the zipper (whoever found a way to keep warm air from leaving out of your zipper deserves a Nobel prize). Plus it has tiny zipper cuts in it, keeping the weight of the bag to an absolute minimum.

It is a 30-degree bag, but you can comfortably be in here at temperatures below 20 degrees.

Should you purchase this

If you are going to be in very cold to freezing climates, then I think this is a bag that would suit your needs. It is rather expensive, so if you are looking for something a bit less expensive, then you might try the North Face instead.

Wrap – Up

We’ve discussed three different types of sleeping bags, and I will say confidently that one of the ones discussed today will do you well (provided you are looking for an ultralight sleeping bag). I will give you fair warning though, if you are not used to sleeping on your back, then these will take some getting used to.

Mummy bags are contoured to fit your body as tight as possible, meaning you won’t have any room to move around in. But the warmth and portability it gives you make it worth the trade off. I hope you liked our post about the best ultralight sleeping bags.

Looking for the top camping sleeping bag? This one is exactly what you are looking for. 

In need of a backpacking sleeping bag? Read about our favorite one here.

Want to know the best sleeping pad of 2019? Check it out here.

Meet the Author

'Mountain Man' John

'Mountain Man' John is a Survival and Preparedness enthusiast who loves everything outdoors. He has a passion for learning anything and everything to help sustain his and his families way of life post SHTF. He frequently shares his knowledge on a variety of topics from his hands on DIY projects, learning new skills such as hunting and trapping along with reviews on his Survival related purchases - Prepping has been in his family for generations, it's in his blood.