Best Ultralight Sleeping Bag: Weightless and Warm

Best ultralight sleeping bag
Written by Dennis Owens

As an avid backpacker or first-time explorer, you might have picked up your pack and wondered: “how am I going to carry this all the way up the mountain?” It might be time to assess your pack and limit the amount of weight you are putting in. To do that, you will need the best ultralight sleeping bag in your pack.

By having a lighter pack, you can go longer and farther on your hikes, and optimize weekend trips to traverse more trails. One simple way to maximize the space in your pack and minimize the weight on your trip is to swap out your bedding accommodations. If you have been shopping around the market you might be overwhelmed by the choices you can make, a wide variety of bags with seemingly infinite options. So, how to make your pick?

In this article we will look at the most important features you should consider before buying a bag, and also give you a list of our favorite products, together with pros and cons, to further ease your choice. Let’s navigate the best ultralight sleeping bags on the market together!

Our Top Picks

Product NameWeightCompressed SizeTemp. RatingPrice
Big Agnes Pitchpine UL20.5 oz.5.5 x 6 in45°FCheck price on Amazon
Western Mountaineering Summerlite Mummy19 oz.7 x 13 in32°FCheck price on Amazon
Mountain Hardwear Mountain Speed16 oz.5 x 8 in32°FCheck price on Amazon
Nemo Tango Solo Down29 oz.10 x 15 in30°FCheck price on Amazon
Marmot Plasma 15 Long34 oz.7.5 x 15 in15°FCheck price on Amazon
Sierra Designs Backcountry Bed Elite25 oz.7 x 14 in30°FCheck price on Amazon
Rab Neutrino Endurance 60039 oz.15 x 8 in7°FCheck price on Amazon

Features to Consider Before Buying

Before we review the bags you need, we will go over a few tips to understand ratings and descriptions so you can say “That’s the bag for me!” Read on to get acquainted with the info you need to make an educated decision.

Upper, Lower, Extreme and Comfort

Each pack will be rated by the temperature in which they are most suitable for, and these ratings will be different for male and female packs. Lower limits and upper limits are often used to describe male-focused packs.

An upper limit is a standard temperature in which an adult man can sleep comfortably with little to no sweat, and a lower limit is for the same individual to sleep, completely curled up without moving. Extreme for women is sleeping for up to six hours without risk of hypothermia. Cozy, right?

Comfortable is sleeping up to eight hours in any relaxed position. Now these are just standards, so if you are chilly at night, fully clothed, in bed, with all the windows closed, play it on the safe side. Be sure to look up to lowest nighttime temperature your backpacking destination reaches, and use that as your limit. Being cold while backpacking can make your trip miserable.

Useful tip: You’ve bought the most beautiful bag ever, but you are still chilly at night? You can always add layers of clothes and blankets inside and outside of your bag to raise the temperature rating.

Insulation Type

There are two major types of sleeping bags you can select from: down and synthetic. Down is made up of goose feathers, is expensive, compresses easier for packing and has a fantastic warmth to weight ratio. If you love this bag right it can last for up to 20 years, which is an excellent investment.

The synthetic option is considerably less expensive, they are better in a wet environment and dry quickly. However, they will be heavier and more difficult to wrap up into a backpacking pack. From one backpacker to another, before you drop loads of money on a down sleeping bag, make sure you are not allergic! If you are, select a synthetic bag and sleep in itch-free comfort.


To keep warm, the sleeping bag should be snug and it shouldn’t let more air come in than what already is inside. The air forms a layer between you and the sleeping bag, and the more air there is, the more time you will need to warm it. Based on this, you should look for designs that fit you better and leave little amount of air inside.

Sleeping bags

The best choice of sleeping bag that won’t let air inside is a mummy bag, because it best envelopes your body, leaving little space between you and the bag. However, you should carefully choose the size, because you still need comfort.

If you don’t want to be constricted in a mummy bag, than you should go with a quilt. When you sleep on top of a down and compress it, it loses its insulating abilities. So, the logic behind quilts is that – since the material below you compresses, there’s no point in carrying it. This is where quilts come in, allowing for a great range of comfortable sleeping styles and the ability to either wrap yourself up in the cold, or spread out and ventilate in the heat.

Zipper Length and Other Things to Think About

So you got the temperature right, but there are still so many options! One that you may not be thinking about is zipper length. Mummy bags, which come all the way up to your head with a hood, come with many different lengths to give the users options.

It may seem crazy, but a shorter zipper is just one of the ways that manufacturers cut down on weight. Your bag may weigh less without the full zip, but you will be giving up the flexibility of your bag to have maximum ventilation, good for summer and winter hikes!

The North Face superlight

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And lastly, if you are going out in the wild wind and rain, keep in mind durable water repellent (DWR). A good DWR treatment will coat the outer shell and cause the water to bead up and roll off rather than soak in. It might cost you a little more, but if you’ve ever slept in a wet sleeping bag for a 5-day trip, you know it’s invaluable.


You are ready to go, your trip is scheduled and it’s time to buy gear for the best weekend in the woods. Before you jump to buying ultralight everything, determine what kind of trip you are going on, and whether or not you plan on sharing supplies in your pack.

Backpacking is different than a weekend of car camping, and your packing restrictions will change depending on proximity to a water source, weather, accessibility to a cooler, miles trekked with the full weight of your pack on your shoulders, and of course, personal preference. If you are planning on a backpacking trip then your pack will need to be light, carry only the essentials and to optimize your pack select either an ultralight or light sleeping bag.

Best Products on Today’s Market

You now have looked at all of your options and you are ready to buy the best bag on the market. Here are a few bags that we think are the best with all the options and customizations I mentioned above for your consideration.

Big Agnes Pitchpine UL 45 Sleeping BagBig Agnes - Pitchpine UL 45

Price: Approx. $350

Weight: 20.5 oz.

Compressed bag size: 5.5 x 6 in

Specific features: Integrated half pad sleeve, water repellent insulation, Pertex rip-stop nylon, WR treatment on surface

Best use: Summer hiking and backpacking trips, rated to go down to 45°F but is more comfortable at 48°F.

Description: The Big Agnes Pitchpine UL 45 Sleeping Bag is made out of Pertex nylon, and it features an integrated half pad sleeve with unique design to keep you securely attached to the pad from the hips up, giving your legs space to move. Big Agnes features a full-length zipper, made for 45-degree temperature, and has a max height of 6 feet 6 inches.

It has a DownTek water repellent down insulation to keep you warm and dry. The Pertex rip-stop nylon is a high thread-count fabric, that is featherweight, soft, and it packs in a small volume. It also features recycled mesh storage sack and nylon stuff sack, built in pillow pockets and interior fabric loops for sleeping bag liners.

Sounds pretty good, huh? This sunflower pack is lightweight, best above 50 degrees (though can go to 45) and the product maker suggests a water-resistant treatment to keep the pack dry and toasty. This pack features a top only design, this means that the down is on the top of your bag trapping in the warmth.


  • Light to carry
  • Very comfortable
  • Half pad sleeve design
  • Made of ripstop nylon outside, soft as silk inside


  • Can only protect you if it is 45 degrees and above, if it’s below that, you will freeze like a mummy
  • Expensive
  • Can only protect you from head to toe if you only stand 6 feet or less

Related: Put your Big Agnes Pitchpine UL inside a Coghlan’s Sleeping Bag Carrier when not in use. Keep it protected from dust and make it easier to transport with this carrier.

Check the price on Amazon

Western Mountaineering Summerlite Mummy BagWestern Mountaineering Summerlite LZ Mummy Sleeping Bag

Price: Approx. $420

Weight: 19 oz.

Compressed bag size: 7 x 13 in

Specific features: Exceptionally light, contains an insulated draft tube, ultimate wind chill protection

Best use: Sleeping in temperatures of minimum 32°F

Description: The Western Mountaineering Summerlite Mummy Bag is true to its name, it’s an ultralight bag perfect for long backpacking trips, but only when trekking through the summertime mountains. Some hikers use it for three-season backpacking but recommend not going below the mid-30s, especially if you are a larger hiker, as there is not much room for additional layers.

While this bag is a bit pricier than its predecessor there are a few key reasons for this. First, the bag is comfortable at a lower temperature which is great for higher peaks, and it is incredibly light.

For backpackers going on the long-haul hikes, this is a light and a compact way to make room for other essentials on your trip. A con to the bag is its dimension, it is a hooded mummy and some testers complain that the hood is not quite big enough for comfort, and it does not expand.

That being said there are a few other benefits to the bag, if you find that you tend to sleep on your side, the stitching on this bag is perfect for you. Summerlite will keep you warm and cozy with its sewing along the bottom.


  • Very light
  • Insulated draft protection inside
  • Can keep you warm even when it is below 30 degrees outdoors
  • 3-season sleeping bag


  • Very expensive

Related: Keep your sleeping bag in place when not in use by using an YYST Sleeping Bag Strap. This strap can also be used to bundle other outdoor equipment.

Check the price on Amazon

Mountain Hardwear Mountain Speed 32 Sleeping BagMountain Hardwear Mountain Speed 32 Sleeping Bag

Price: Approx. $400

Weight: 16 oz.

Compressed bag size: 5 x 8 in

Specific features: Enjoy a down fill with advanced water treatment that allows for maximum warmth in wet conditions. This bag is extremely lightweight with a half zipper and a five chamber hood to trap heat.

Best use: Sleeping in the mid 30°F temperature range

Description: With their advanced Ghost Whisperer fabric shield, the Mountain Hardwear Speed 32 can stay comfortable in the mid-30s range. Packing down to almost this size of a Nalgene water bottle, you can feel good about saving room in your backpacking pack. It’s warm for its weight and can be a good choice for a three season bag.

Hardwear Mountain Speed can go into the same cold range as Summerlite but runs a little less expensive, there are a few key reasons for this. One is that the bag does not offer a full zipper, so in warmer summer hikes you won’t get the full ventilation and may overheat.

Also in order to save weight, the mummy bag is cut tightly, meaning there isn’t a lot of room to add layers into the bag if you find your self-cold at night.

One last thing to note about this bag is the relatively low reviews. This is due to complaints around the zipper performance.

It seems that backpackers are struggling with the zip getting caught, it is too flimsy and overall too small. This can be frustrating in the middle of the night when you find yourself stuck in a mummy bag, or worse zipped out of it in the cold.


  • Made of whisperer fabric
  • Moist resistant
  • Ergonomic design to keep you warm from head to toe
  • Very light
  • The design ensures that the head is protected and warm all night long


  • Customer complaints were about its zipper easily breaking

Related: Carry your Mountain Hardwear Mountain Speed 32 comfortably anywhere you go by putting it inside an AEGISMAX Compression Stuff Sack. It comes in different sizes so make sure to get the sack that fits your sleeping bed.

Check the price on Amazon

Nemo Tango Solo 30 Sleeping BagNemo Tango Solo 30-Degree Down Sleeping Bag

Price: $200-$300

Weight: 29 oz.

Compressed bag size: 10 x 15 in

Specific features: DownTek 700-fill-power down, excellent water-repellent treatment, a snap-on hood, packs down small and weighs less

Best use: Sleeping in over 30°F and low 40°F

Description: What big time backpackers love the most about the Nemo Tango Solo Sleeping Bag are the roominess and the versatility. Unlike a mummy bag, hikers find that they can easily sleep on their sides and toss and turn throughout the night without fear of warmth escaping. The snap-on hood provides comfier additional heat, and the fabric of the comforter is soft and comfortable.

The sleeping bag perfectly attaches with a Nemo Cosmo sleeping pad, which is sold separately, and it works with most 20-ich wide pads. Some say that they wish the comforter would allow for a wider sleeping pad, at its optimal use the bag is tucked into a 20 or 25 in the wide sleeping pad.

It is filled with DownTek 700 duck down, which is water-repellent and it maintains its insulating properties in the most humid conditions. It doesn’t have a back, lowering the weight and the volume of a typical bag.

Finally, there are some concerns about there being bare spots in the down where you can feel the cold through.


  • Spacious design to allow user to wiggle while inside
  • Can keep you warm even at below 30-degree weather temperature
  • Made of 20-denier nylon fabric for added durability
  • Comes with breathable foot box


  • Most customer says it doesn’t really keep you warm once the temp hits 50 degrees

Related: Make your night more comfortable and warmer by adding an OUTRY Travel and Camping Sheet in your sleeping bed! This sheet is made of cotton, it has an underneath pouch to cover the pillow, and the front sheet can be folded back to cover to top of the quilt.

Check the price on Amazon

Marmot Plasma 15 Long Sleeping BagMarmot Plasma 15F Degree Down Sleeping Bag

Price: Approx. $700

Weight: 34 oz.

Compressed bag size: 7.5 x 15 in

Specific features: 875-fill goose down with Down Defender water-resistant

Best use: Sleeping outdoors in very cold weather

Description: The Marmot Plasma 15 Sleeping Bag’s special feature is that the mummy bag has Insotect flow vertical baffles, this is meant to help with keeping both your core and extremities warm in cold weather. There are also two-way zippers and an insulated draft tube.

Marmot has designed this bag to go as low as 15°F, it is normally used for three-season backpacking, but some users have brought it on winter camping. Now, this bag is on the pricier end, but the simple reason is that it can go in extremely low temperature without having a lot of weight added to your backpacking pack.

Most users have noted that they are heated from their core and the bag directs that heat down to their fingers and toes, which is quite the lifesaver on cold nights. This bag also has high ratings on durability and its water-resistant treatment.

Like most mummy bags the biggest complaint is that for larger chested hikers, this bag can be a bit too snug and limit the amount of movement at night.


  • 3-season sleeping bed
  • Features an 875+ fill Goose Down for optimum warmth
  • Super lightweight
  • Water resistant and moist resistant


  • Very pricey

Related: Use a Marycrafts Artificial Silk Sleeping Bag Liner to keep your nights warmer inside your Plasma Sleeping Bag. It is machine washable, lightweight, and easy to carry.

Check the price on Amazon

Sierra Designs Backcountry Elite Sleeping BagSierra Designs Backcountry Bed Elite 30 Degree Sleeping Bag

Price: Approx. $250

Weight: 25 oz.

Compressed bag size: 7 x 14 in

Specific features: Zipperless foot vent, insulated hand and arm pockets, comfort rating: 30°F, 850-fill duck DriDown

Best use: 2 seasons, 30 degree

Description: The Sierra Designs Backcountry Elite Sleeping Bag was built for backcountry hiking and camping and has a featured down-filled quilt flap that can be folded down to your waste or pulled all the way up to your neck. If you are a restless sleeper who ranges from hot to cold throughout the night, this bag is for you.

Unlike most bags on the market, Sierra Designs chooses to go with a zipperless design in their integrated comforter. It is insulated with 850 fill Duck DriDown, comes in a multitude of sizes and has a self-sealing foot vent.

While at first look the design may seem a bit silly, reviews and testers note that they are warm, comfortable and able to move and adjust as needed. The sides are made extra wide which allows for plenty of rolling around and is perfect for the vast temperature range that is known for backcountry camping.


  • Made of nylon
  • 30 degree sleeping bag, allows user to move comfortably inside
  • Innovative Zipperless foot vent
  • Comes with insulated hand & arm pockets
  • Affordable


  • Only useful to people that are below 5’8 tall

Related: Keep your nights warmer by placing a Forbidden Road Sleeping Bag Liner in your Sierra Sleeping Bag. Made of cotton, it is warm, soft, and durable.

Check the price on Amazon

Rab Neutrino Endurance 600 Sleeping BagRab Neutrino Endurance 600

Price: Approx. $500

Weight: 39 oz.

Compressed bag size: 15 x 8 in

Specific features: Rated at 7°F, it zips into other Neutrino Endurance bags, 800-fill goose down, Pertex Endurance, 30D nylon, DWR coating, [lining] Pertex Quantum, 20D nylon, DWR coating

Best use: Alpine climbers, lightweight mountaineering trips, cold temperatures

Description: The Rab Neutrino Endurance 600 Sleeping Bag is made with minimum weight and packs size without giving up any precious warmth. It is a snug mummy shaped bag with 800 fill European goose down with both left and right-hand full zipper options added.

This ultralight bag can go with you to temperatures as low as 7°F and is rated at the 0-10 range. The Pertex fabrics on the outside of the back offer ideal protection for cold and damp climates and is a mummy tapered shape to pack up small.

Users of this bag praise its warmth and its ability to keep them dry in wet climates. What this bag does different, is that it went one step further on its insulation, it repeals any built up condensation from clumping and seeping in so you can be sure you will be dry all night.

If you are worried that the temperatures you are hiking in are going to plummet, leaving you out in the cold, this is the bag to bring. Winter expedition bags tend to run expensive and are heavier, this reasonably priced back keeps the heat in and the price down.


  • Made of 30D nylon
  • With DWR coating
  • 800-fill goose down insulation for added warmth
  • Half-length zipper


  • The maximum user height is just 5’7

Related: Keep your Rab Neutrino Endurance 600 Sleeping Bag inside an AEGISMAX Compression Stuff Sack when not in use or when transporting it.

Check the price on Amazon

Wrap Up

These are just a few products out there on the market, and as I said before you have many options to choose from and many specifications to look over.

What is essential in picking out your bag is not necessarily the most expensive or highest rating, but rather our own personal sleeping habits and the need for warmth. We are all different, so just because the bag is rated best on market, does not mean it is best for you.

After purchasing your bag take it on a few car camping trips before jumping out and onto a chilly trail to make sure it is the right fit for you. There are a lot of bags out there, but we want to know what you think is the most versatile, if we’ve missed one in our review tell us in a comment below!


Dennis Owens

Dennis Owens is a graduate of National Camping School and REI Outdoor School. He knows everything about what gear to take with you, how to plan your trip to stay safe and what to do if you get lost in the mountains. We are lucky to have Dennis with us as he is a ‘walking encyclopedia’ when it comes to the wilderness.