Best Mummy Sleeping Bags of 2024

BEST SLEEPING BAG FOR SIDE SLEEPERS

The Big Agnes Sidewinder SL20 is spacious enough to be a game changer for side sleepers but it doesn’t trap cold air as much as other wide options.

What we love the most about the Sidewinder SL20 is that it’s one of the only bags on this list that is truly built for side sleepers. The zipper and the hood face the side. The insulation and shape are all geared toward those who roll over. There is a mesh pocket for your pillow that keeps it in place. There is extra padding at the hip and feet, which are two pressure points for those who tend to flip from side-to-side several times throughout the night. There is plenty of room to curl your knees up without feeling constricted as you might in a mummy bag. 

One complaint we have with this bag is the zipper catches if you aren’t careful despite having an “anti snag zipper”. Maybe we were too rough with it but this could be annoying if you have to get up in the middle of the night. Also, people with wide feet might find the toe box a bit tight. 

The Nemo Disco 15, which is also featured on this list is a close competitor to the Big Agnes Sidewinder SL 20. The Sidewinder gains points on weight (it’s 7 ounces lighter), but it is not as roomy as the Disco. The extra inches on the shoulders and hips are nice but you also have to consider that it’s not the best design for retaining warmth.

The Big Agnes Sidewinder SL 20 also comes in a women’s version.

The Marmot Sawtooth is a quality down sleeping bag that incorporates a healthy mix of warmth and water protection given the price. With a comfort rating of 27.1 degrees F, the Marmot Sawtooth will keep you warm on most 3-season backpacking trips. 

For peace of mind when moisture strikes, this down sleeping bag not only incorporates water-repellent down but a durable water-repellent shell as well. The drawcord collar is a nice touch to help cinch this bag down and block out the cold. Should you find temperatures to be colder than expected, stuff a heat packet into the heat pocket at the bottom of the bag and keep your toes nice and toasty.

The Kelty Cosmic 20 is a budget minded down sleeping back that is a great option for new backpackers who don’t mind carrying a bit of extra weight and bulk to save some cash.

What we love the most about this bag is its overall value. The Cosmic’s quality and warmth are great considering how inexpensive it is. Of course, you can’t compare the build and material quality of the Cosmic to the top of the line bags on this list but it is practical and comfortable enough, making it tough competition for other budget options.

The biggest downside of the Cosmic is it is much more heavy and bulky than other backpacking sleeping bags, but hey, it’s one of the cheapest down bags around. If you’re just starting out, you could always go for the Cosmic and if you end up becoming a hiking junkie, you could upgrade and retire this bag to car camping adventures. 

This bag is also offered in 40-degree and 0-degree versions. 

The Kelty Cosmic 20 is also available as a women’s version. 

The Therm-a-Rest Hyperion 20 is a lightweight high quality bag that was designed to help long distance hikers shave pounds from their load.

What we love the most about this bag is its warmth to weight ratio. It’s filled with 900 down which makes it so warm and light. It also packs down quite small, making it great for saving room in your backpack. A little feature we liked was there are two straps underneath it which you can attach to your sleeping pads to keep the bag from slipping off. The Hyperion comes with a compression bag which helps get the bag down to about the size of a large water bottle. There is more insulation on top (70%) and less on the bottom (30%), this saves weight but it also means the design is optimized for sleeping on your back. 

What this bag gains in weight saving, it pays for in comfort. The cut is slim, very slim. So, if you’re a bigger dude or lady, you will probably feel constricted in this thing. The Hyperion is very narrow throughout and tapers down even more at the feet. The zipper only goes halfway down the bag, which does shave some ounces but it also means you can’t vent your feet. And, while we’re talking about the zipper, let’s just say it has some room for improvement. There’s a bit of fabric that runs along the zipper but it still snags from time to time. 

The Hyperion 20 is excellent value for money and is cheaper than other high end bags on this list, but it is lacking some features like a draft collar that lets you seal the bag around your face. Also, while it’s rated to 20 degrees, its comfort rating is 32 degrees. So we only recommend this  bag for above freezing conditions. If you’re the kind of hiker who doesn’t mind sacrificing some comfort in order to go fast and light, the Hyperion 20 could be the perfect bag for you. 

This bag also comes in a 32 degree version.

BEST BACKPACKING SLEEPING BAG UNDER $100

The Marmot Nanowave 45 is an affordable summer sleeping bag that won’t take up too much room in your backpack. Not only is it cheap, it’s practical and functional which is why it’s our pick for the best backpacking sleeping bag under $100. 

In awarding it the winner of the best under $100 category, we realize it’s not quite fair because most other bags on this list have a temperature rating down to around 20 degrees. However, if you’re on a super tight budget and plan to camp from mid-spring to mid-fall, the Nanowave 45 is hard to beat.

Which leads us to the biggest downside of this bag, it is only good in mild weather. But, not everyone needs or wants a super warm bag and if you combine the Nanowave with an extra warm sleeping pad and a thermal liner, you might be able to extend the temperature range of this bag down a few degrees, making it much more versatile. If you’re looking for a warmer budget backpacking sleeping bag, check out the REI Trailbreak 20 which is also featured on this list. 

The Marmot Nanowave is also available in a 55-degree and 35-degree version.