If you’re in a rush and want to find out what the smallest sleeping bag when packed is, we recommend the Big Agnes Torchlight 20 sleeping bag.
Compact sleeping bags are practically a requirement for backpackers, but they’re also nice to have for the occasional car camper as well. No one wants to lug around a bulky mammoth of a sleeping bag, after all.
But aside from trying them out in the store, how are you supposed to know if they pack down well? What metrics are used? We’ll talk about these things and more, in addition to laying out some of our favorite smallest sleeping bags when packed.
In this article, we’ll be reviewing the following smallest sleeping bags when packed:
- Sea to Summit Spark Ultralight 18F Sleeping Bag – Best Ultralight Sleeping Bag
- Big Agnes Torchlight 20 Sleeping Bag – Best Overall
- Kelty Cosmic 20 Down Sleeping Bag
- Marmot Helium Down Sleeping Bag
- REI Co-op Women’s Magma 30 Sleeping Bag – Best Sleeping Bag for Women
- Therm-A-Rest Questar Sleeping Bag – Editor’s Choice
- Marmot Voyager 55 Sleeping Bag – Best Cheap Sleeping Bag
- REI Co-op Down Time 25 Sleeping Bag – Best Bang for Your Buck
Size
An obvious factor to consider for any camping gear, size is especially important when it comes to finding a good, compact sleeping bag. But aside from its packed size, you’ll also want to consider how big it is when rolled out, as well.
In colder weather especially, having a sleeping bag that’s too large can leave you feeling chilled and uncomfortable. When there’s so much extra space inside your bag, you run the risk of creating cold air pockets that will haunt you until you finally give up on having a decent night’s sleep. Likewise, if you go too small, having the sleeping bag material compress around your head and feet can be just as uncomfortable.
Ultimately, you should try to find a bag that gives you roughly two inches of extra room beneath the bottoms of your feet. This will still allow you to stretch out a little, without creating so much room that you start to give cold air a home.
Shape
Generally speaking, there are only three different shapes for you to choose from: mummy, rectangular, and semi-rectangular. Here’s a brief overview of the differences:
- Mummy. By far the most popular style, mummy sleeping bags make you feel like…well…a mummy. With the tapered design, you’ll be able to cut back on weight while increasing thermal retention, letting you stay warmer with less effort. Of course, the tighter fit can be a little uncomfortable for those of us who like to spread out in our sleep, but they’re the most efficient option to go with. Naturally, because of their leaner shape, they also pack down the smallest, which is why we’ll be talking about them exclusively in this review.
- Rectangular. Incredibly comfortable, rectangular bags are usually found at car camping sites. Because they’re a little heavier, and often have more padding shoved inside of them, they aren’t ideal for backpacking. But when you pair one with a camping cot and pillow, you may start to forget that you aren’t back home in your own bed.
Because of the rectangular shape, there’s more space inside for you to spread out. If you’re a side sleeping, you’ll really appreciate the extra room, since you can’t sleep this way in a mummy bag (though there are a few exceptions). The additional space does mean that they lose heat faster, so they aren’t ideal in temperatures below 60 degrees or so.
- Semi-rectangular. Like their rectangular counterpart, semi-rectangular bags are wider near the shoulder to give you more breathing room. However, they start to taper down toward your feet, offering better heat retention. For a good balance between warmth and space, this might be the style for you.
Insulation Type
When it comes to sleeping bag fill types, you really only have two options. Down is my personal favorite, as it’s by far the warmest material by space (as in, you need less of it to stay warmer). And because you don’t need as much, it’s much easier to compress it down into a tight space, making it the optimal fill for the smallest sleeping bag when packed. The downside is that it loses its insulation capabilities when wet, but that shouldn’t be a problem unless you have a hole in your sleeping bag, or the outer lining becomes too saturated.
Your other option is going to be a synthetic fill. There’s nothing inherently bad about it, and several of my friends have exclusively gone this route because it’s much cheaper. It will also continue to insulate you even when wet, making it perfect for more humid climates.
However, that’s where the benefits end, in my opinion. Synthetic is heavier and harder to compress than down, and won’t keep you as warm as down. As a rule of thumb, though, it’s often safe to say that you should use down when you’re camping in a colder, drier environment, and you should use synthetic when you’re in a warmer, humid environment.
Stuff Sack
If you’re concerned about how compact your sleeping bag will be when it’s packed away, you should pay close attention to the compression sack you keep it in. Many (not all) sleeping bags come with two storage bags – one for at home storage, when you aren’t using it, and one for trail storage. The sack for storing your bag at home is usually quite large and made from mesh, giving your sleeping bag plenty of room to relax and breathe. This helps increase its longevity and overall heat production.
The compression sack is what will squeeze your sleeping bag into a nice, compact space, taking up a minimal amount of room in your backpack. Ultimately, this sack is what will determine how small your sleeping bag can get when packed. While you can measure it using inches, the space in a stuff sack and the size of a compressed sleeping bag is typically measured in liters.
Warmth Rating
This relates back to what we mentioned when discussing sleeping bag shape and insulation type. Mummy bags filled with down are generally going to keep you the warmest, while a synthetic filled rectangular bag won’t do very much at all.
All sleeping bags come with a temperature rating, though, which tells you the coldest temperature you’ll be able to stay comfortable at when inside the bag. This is the tested comfort limit. There’s also a minimum temperature rating, which is the coldest you can “uncomfortably” sleep inside the bag, also known as the tested lower limit. When possible, I would recommend using the sleeping bag down to its tested comfort limit, unless you plan on using a sleeping bag liner with it.
Smallest Sleeping Bags When Packed – Reviewed
Sea to Summit Spark Ultralight 18F Sleeping Bag
When backpacking, the weight of each individual item should be carefully scrutinized. As shocking as it might sound, even a few extra ounces can make a big difference when you’re carrying all your belongings on your back for hours on end. Which is precisely why an ultralight sleeping bag, like the Sea to Summit Spark, is an invaluable resource. Weighing in at a mere 1.5 pounds for the regular size, it’ll be very difficult to find something that can match those specs.
Ultimately, though, it comes down to what you want in a sleeping bag. While the Spark might not weigh very much, it also won’t be your best option in colder weather, especially if it’s below freezing. However, considering how light it is, and the overall reduction in materials used, it is a fantastic option for a compact sleeping bag.
In general, I’d say this sleeping bag is best used for backpackers who like to get out anytime between late spring and early fall. With that said, you’ve got an even narrower window if you enjoy alpine camping. Depending on the location, I wouldn’t suggest using this in the mountains during any time other than May through August (and possibly September).
Pros:
– Ultralight
– Decent heat retention considering how light it is
– Vertical chest baffles to prevent the insulation from migrating
– Nice mummy contouring for maximum efficiency
Cons:
– It’s quite tight and the zipper is short, so getting in and out can be a challenge
– A bit on the expensive side
Big Agnes Torchlight 20 Sleeping Bag
I’ve always been a fan of Big Agnes and the gear that they make. They’re known for creating products with unique features that push the boundaries of what camping gear can do. And in the case of the Torchlight, there’s more than one trick that will make you fall in love with it.
For instance, it’s said that 74% of the population prefers to sleep on their side, but as we know, mummy bags aren’t usually good for this. But if you look closely at the Torchlight, you’ll notice that it has an expandable panel that can be unzipped to create an extra 10 inches in circumference. As a side sleeper myself, I can’t tell you how nice it is to have that extra space in the shoulder region. And at just under 3 pounds, it’s a fairly lightweight bag, especially when you consider how warm it actually is.
The zipper on the left side can be combined with another sleeping bag to create a double sleep setup. It’s the perfect choice for couples who don’t want to be apart during the night, letting them stay close and share heat. Not that you really need to, since the Torchlight has a comfort rating of 27 degrees.
But you’re looking to find one of the smallest compressed sleeping bags, so how does the Riff hold up? Well, when fully compressed, it takes up about 7 liters (for easier measurements, the stuff sack is 9 x 20 inches). Not too bad, if you ask me!
Pros:
– High quality sleeping bag
– Keeps your comfortable down to 30 degrees
– Pretty small when packed
– Weighs 3 pounds
– Expandable panel
– Can be combined with another sleeping bag
Cons:
– Somewhat narrow footbox
Kelty Cosmic 20 Down Sleeping Bag
It’s difficult to find a high-quality sleeping bag that you can put through the paces, for as low of a price as Kelty’s Cosmic. Keeping you comfortable down to 32 degrees, you’d expect something that powerful to weigh a ton. But I believe Kelty was able to keep it down to 2.5 pounds primarily because they used a down fill – something far more lightweight and compactible than synthetic insulation.
It comes with a draft collar to keep the cold air outside and the warm air inside, as well as an internal pocket to store your headlamp and phone. The shaping is very natural and comfortable, though a little too tight for side sleepers to get a good night’s rest. And for those of you who are tired of dealing with sticky zippers, they couldn’t be smoother on the Cosmic.
Packability is one of the best I’ve seen in a sleeping bag as well, which is probably what you really wanted to hear. The size of the regular stuff sack is 8×13 inches, which roughly equates to 9 liters, though the size of the compressed sleeping bag will be less. Either way, you’ll be able to pack it away pretty easily, with plenty of room to spare for all of your other gear.
Pros:
– Very warm
– Reasonably priced
– Down insulation
– Smooth zippers
– Comfortable interior
– Interior pocket
Cons:
– A little tight fitting
Marmot Helium Down Sleeping Bag
Marmot has always been one of my favorite brands, especially when it comes to their tents. I’ve always found their gear to be some of the highest quality equipment on the market, and that translates to their sleeping bags as well. The Helium, in particular, is a very impressive product, despite the somewhat bland color design.
It’s one of the warmest bags that we’ve reviewed so far, able to keep you safe and comfortable down to 15 degrees. Like the Cosmic we just talked about above, the Helium is also filled with down insulation, reducing the overall weight of the bag while making it easier to pack down. It comes with an anatomical footbox and nautilus hood to fully envelop you in warmth without sacrificing on space or breathability.
The stuff sack is 7×14 inches, or 8.8 liter to be exactly. Certainly not the smallest sleeping bag when packed, compared to some of the others that we’ve mentioned, but it’s still well within the realm of highly compressible bags. I’d feel comfortable bringing this product with me on any backpacking trip where I’d expect to encounter colder temperatures, especially considering it only weighs a smidgen over 2 pounds.
On the inside, you’ll also find an internal storage pocket for your personal belongings. On the outside, there are two hang loops that let you store and hang your sleeping bag, helping it to air out and maintain its loft.
Pros:
– Incredibly warm
– Lightweight
– Cozy and soft
– Internal storage
– Loops to hang your sleeping bag
– Packs down small
Cons:
– Zippers may unzip a little on their own
REI Co-op Women’s Magma 30 Sleeping Bag
I’ve just got to say, REI outdid themselves with the women’s Magma 30 sleeping bag. It’s one of the warmest sleeping bags in this review, able to keep you comfortable in temperatures that dip down to 29 degrees. And that’s saying something since this bag was designed for women, who have a harder time staying warm anyway!
In spite of the impressive cold weather performance, it also packs down the smallest out of any product we’ve talked about so far. The stuff sack is 6×14 inches with a 6.5 liter capacity – the compressed sleeping bag itself only takes up 3.4 liters, when you get the regular size. That’s really small, especially when you consider everything you get with this bag.
The goose down works together with the contoured hood and baffle system to increase thermal retention. And since it was specifically designed for women, the hip section is a little wider, while the shoulders are narrower to keep the heat trapped inside. With a large, heavily insulated footbox, you’ll still have enough room to stretch out a little without creating any cold air pockets.
Did I mention that it only weighs about 1.5 pounds? I’m still trying to keep my jaw closed after discovering how tiny and light the REI Magma 30 sleeping bag actually is.
Pros:
– Lightweight
– Packs down really small
– Goose down
– Keeps you comfortable down to temperatures below freezing
– Anti-snag zippers
Cons:
– Can feel a little tight if you have some extra weight on you
Therm-A-Rest Questar Sleeping Bag
The ultimate lightweight, highly compressible sleeping bag, Therm-A-Rest’s Questar is an ultralightweight backpacker’s dream come true. Weighing just 2 pounds, it’s only a hair heavier than the Sea to Summit Spark mentioned above, which is already pushing the limits of weight reduction. But on top of that, the really neat part about this product is that it’s one of the smallest sleeping bags when packed – a mere 5.4 liters when fully compressed. That translates to a stuff sack that’s 9×7.5 inches, which is pretty tiny.
Naturally, there are some things that you have to give up when you get a sleeping bag like this. They say it will keep you comfortable down to 32 degrees, but I’ve found it to be closer to 38 degrees. Not a huge shift, but enough to make you uncomfortable if you’re pushing the limits on the rating. At the very least, I would suggest pairing this bag with a sleeping bag liner, though I would also recommend that for any product listed in this article.
Overall, the Questar is a very comfortable bag with an attractive color scheme. It’s definitely for those of you who value packability and reduced weight, as opposed to car campers and less serious backpackers.
Pros:
– Ultralightweight
– Packs down super small
– Comfortable to sleep in
– Nice colors
– Down fill
Cons:
– Zippers can be irritating
– Not for very cold temperatures
Marmot Voyager 55 Sleeping Bag
Designed for adventurers on the go, Marmot’s Voyager may not be the warmest bag out there, but it’s certainly one of the smallest. It was specifically created for bikers needing to stuff a sleeping bag in their pannier, kayakers who need something that will fit in a stern compartment, or backpackers who want to free up more space in their pack. Needless to say, it packs down really small, and the weight is just a bit under 2 pounds so it’s easy to carry.
In terms of seasonality, I would suggest using this bag during May through September. It offers a reasonable amount of warmth, but it definitely won’t keep you comfortable in temperatures that dip to 40 or lower. Unless, of course, you paired it with a liner, sleeping pad, and proper layering.
But you can’t complain too heavily about the lack of warmth, as it really was meant to be used as a fair weather sleeping bag that doesn’t take up much space. And for the price, I have no problem recommending it for the value that you get.
Pros:
– Very compact when compressed
– Lightweight
– Cheap
– Synthetic material is great for those allergic to down
– Comfortable
Cons:
– Not the warmest sleeping bag out there
REI Co-op Down Time 25 Sleeping Bag
Another cheaper option, REI’s Down Time 25 is pretty impressive for the price. It says it will keep you comfortable in temperatures down to 35 degrees, which I would say is pretty accurate. Though you may want to throw on some warmer clothes or have a good liner, if it happens to get that colder than that at night.
At 2.7 pounds, I would say it weighs slightly above average, but not by much. And despite the additional ounces, it only takes up 6.3 liters of space when compressed, which is better than most options on the market. The interior is soft and comfortable, but the zippers do like to snag quite frequently. If that’s not the sort of thing that bothers you too much, though, then you shouldn’t have many complaints about this bag.
I will say that it’s not for big men. The shoulders are a bit tight, so if you’re broad in the chest, I wouldn’t really recommend you go with this product. Smaller men will be able to appreciate it more, otherwise I know of plenty of women who opted for this men’s version of the Down Time instead of the women’s model. It’s roomier and seems to fit a female frame better than the one designed for women.
Pros:
– Packs down small
– Inexpensive
– Soft and comfortable interior
– Great for small men or for women
– Works well in the warmer months
Cons:
– Tight fit for larger men
– Snaggy zippers
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Smallest Sleeping Bags When Packed: Final Verdict
I don’t like to make assumptions, but you’re probably looking for the smallest sleeping bag when packed because you plan on backpacking with it. And if you’re backpacking with it, that means you need to consider other factors like weight, size, warmth, and durability as well. Taking all of these points into consideration, it was the Big Agnes Torchlight that we found to be the best highly compressible sleeping bag that doesn’t skimp on the area where it matters most.
Despite the fact that it packs down into a 7 liter space, the sleeping bag itself is incredibly spacious, even allowing side sleepers to rest comfortably. Because of the high loft down, you’ll also be able to stay warm and comfortable in cold temperatures, letting you use the bag in a wider variety of climates.
