A proper sleeping bag is one of the most important choices for any backpacking trip. When you are looking for a 0 degree sleeping bag with a perfect balance between warmth, weight, comfort and functionality, you’ll quickly find that there are A LOT of options out there.
Our favorite option is the Teton Sports Altos Ultralight Mummy Sleeping Bag.
That’s why we’ve created this guide to share the very best winter sleeping bags in the market.
Our Top 0 Degree Sleeping Bags
- Best Overall – Teton Sports Altos Ultralight Mummy Sleeping Bag
- Best lightweight option – Outdoor Vitals Summit Down Sleeping Bag
- Best for Space –OmniCore Hooded Rectangular Sleeping Bag
- Best for Compression size – Outdoor Vitals Atlas Down Sleeping Bag
- Best pick for Money – Hyke & Byke Goose Down Sleeping Bag
5 Best 0 Degree Sleeping Bags Reviewed
1. Teton Sports Altos Ultralight Mummy Sleeping Bag
Pros
- Spacious inner space, doesn’t feel cramped
- Soft and comfortable against your skin
- Has handy zipper pockets
- Made of DriDown for water resistance
- Keeps you toasty warm in cold weathers
- Well designed two-way zippers that don’t snag
Cons
- Doesn’t have a great compression size
- Weighs 4.2 pounds
Bottomline
The TETON zero degree sleeping bag is a win-win for cold weather. It meets all the good features of a sleeping bag somewhere in between – material, price, weight , comfort and warmth.
2. Outdoor Vitals Summit 0°F Sleeping Bag
Pros
- Spacious
- Warm enough in actual 20F temperatures
- Comfortable lofts
- Good compressibility
- Grid baffle design to ensure Down doesn’t shift
- Vital Dry DWR coating for water resistance
Cons
- Zipper snags at times
- Not waterproof
- Drawstrings are not very flexible
Bottomline
A solid sleeping bag, an allrounder. Weighing the pros and cons, we would term it as the Best Bang for the Buck.
3. OmniCore Designs Rectangular Sleeping Bag
Pros
- Made of ripstop Nylon and super comfortable inner lining
- Innovative hood mummy design that offers generous space to move around
- Comes with a DWR coating for weather resistance
- Included compression sack
- Has stash pockets for easy organizing
- 3D constructed Down filling traps keep and keeps you real warm
Cons
- A tad heavy for backpacking
- Zippers tend to open at night
Bottomline
A heavy duty winter sleeping bag that you can rely on, that’s made of the best materials and a well-thought out design.
4. Outdoor Vitals Atlas Down Sleeping Bag
Pros
- Made of good quality Nylon shell fabric
- Two bags of the same model can be zipped into make a double sleeping bag
- Compact compression size
- Comes with a limited lifetime warranty
- Lightweight for this price range
- Priced reasonably
Cons
- Bulky for backpacking
- Lower down fill power – lesser warmth
- Bit snug for an adult
Bottomline
A decent sleeping bag at a reasonable price that performs well, compresses good and is lightweight.
5. Hyke & Byke Goose Down Sleeping Bag
Pros
- Best price for 800 down fill
- Ultralight
- Exceptional weight-to-warmth ratio
- Silky smooth material that feels great against your skinBest for backpacking
- Made of high quality baffle & filling
Cons
- Narrow & feels a little stuffed at times
- Slight odor detected by some that wears away with time
Bottomline
A budget ultralight sleeping bag with the best warmth-to-weight ratio you can get.
What should you consider?
Price
Your sleeping bag will probably be one of the most expensive items in your backpack, but it could easily be your favorite piece of gear too.
Winter sleeping bags can easily top $500 since they need to be made of the best materials to be able to withstand extreme temperatures. We’ve heavily factored cost into our choices to recommend the best zero degree sleeping bags with great quality and value.
Weight
Your sleeping bag will be one of the four heaviest items in your backpack (shelter, backpack, sleeping bag, sleeping pad). That’s why it’s critical to strike a balance between warmth, comfort, and weight with your choice.
It won’t take long to get sick of a heavy and bulky sleeping bag, but you don’t want to compromise on warmth either.
In an ideal world, you’d own 2-3 sleeping bags to choose from depending on the trip. Most backpackers start out by choosing one bag that will keep them warm at the lowest temperatures they plan to hike in. We have shortlisted winter sleeping bags ranging from 2.11 to 5.6 lbs from which you can choose one based on your requirement.
Warmth
Sleeping bags don’t create warmth, your body creates warmth. Your sleeping bag keeps you warm by trapping body heat in an enclosed space.
Sleeping bags with more insulation trap heat better, so they’re warmer. Sleeping bags with lots of interior space are less efficient because they create a larger area for your body to warm up.
4 out of the 5 0 degree sleeping bags reviewed here are Mummy styled bags, taking this into consideration.
Fit – Quilts or Mummy bags?
Down quilts have steadily gained in popularity over the past few years, especially among ultralight backpackers. The reasoning is simple: down quilts provide the best warmth-to-weight ratio of any backcountry sleep system.
They do this by cutting out the material and insulation that’s normally compressed under your body in a mummy bag. With a quilt, you’ll sleep directly on your pad and it feels similar to a down comforter.
Quilts don’t have hoods, so it’s important to pack a warm hat or hooded clothing (puffy coat) for chilly evenings. Most quilts have pad attachment straps to help hold in heat, but mummy bags work better in cold/windy conditions because they’re less drafty.
We generally prefer the flexibility, weight, and comfort of quilts when nighttime temperatures are above freezing (32°F). Mummy bags are preferred when temps dip below freezing.
Temperature Rating
Sleeping bags come with temperature ratings to help you choose the best bag for the conditions you’ll be hiking in. Sadly, temperature ratings in the sleeping bag industry tend to be misleading and exaggerated.
So don’t expect that new 15° sleeping bag to actually keep you warm down to 15°F.
That’s likely it’s “lower limit” rating, meaning it’ll keep you alive down to 15°F, but you’ll be in for a cold, sleepless night.
“Comfort ratings” are usually about 10-15° warmer than “lower limit” ratings, and we find them to be a much better estimate. If no comfort rating is listed, we usually estimate an extra 10-15° to the lower limit for mummy bags and 20-25° for quilts.
EN Ratings
European Norm (EN) is a standardized temperature rating system. It keeps ratings consistent across the industry, but not all companies use EN ratings.
The number listed with most sleeping bags (example: Magma 10) is the EN Lower Limit, which is usually 10-15 degrees lower than the EN Comfort Rating.
In general, bags with EN Lower Limits between 10°F and 30°F are considered good 3-season bags (spring, summer, and fall). But that will largely depend on individuals and the conditions they hike in (see “choosing a temperature rating” section below).
Choosing a temperature rating
Sadly, choosing the right temperature rating for a sleeping bag or quilt is not an exact science. Men tend to sleep hotter than women (usually by about 10 degrees) and some people are “hot sleepers” or “cold sleepers.”
Combine that with the fact that a bunch of other factors contribute to warmth (sleeping pad insulation, clothing, hydration, nutrition, altitude, etc.).
Now things are just downright confusing, aren’t they?
For this list, we choose the best winter sleeping bags with temperature ratings that we feel will be a good fit for most 3-season backpackers. Most of the bags on this list will keep the average user comfortable when temperatures dip to freezing, or a few degrees below.
If you know you’re a hot or cold sleeper, you may want to adjust your choice accordingly.
Increasing Temperature Rating
Another thing to keep in mind when choosing a sleeping bag is that you can always increase your warmth by adding layers. For example, wearing a down jacket with a hood inside your sleeping bag will significantly boost your warmth.
You can also sleep in wool base layers, a warm hat, gloves, and even your raincoat/pants if things get truly frigid.
Other tricks include eating a meal right before bed, staying well hydrated, putting a hot water bottle inside your sleeping bag by your feet, and finding natural insulators (like pine needles) to put under your sleeping pad.
Fill material – why choose Down insulation over Synthetics?
When it comes to sleeping bag insulation, there are two main types: down and synthetic. Down insulation is more expensive but has a better warmth-to-weight ratio and compresses more. Down insulation bags also last longer than synthetic bags if taken care of properly.
Synthetic insulation bags tend to be less expensive than down bags and retain heat somewhat better when wet. Synthetic bags tend to be much bulkier and weigh more than down bags.
In our opinion, down bags tend to perform far superior, so they make up the majority of our recommendations.
Down Fill power
The fill power (fp) of a down bag measures the quality of the down insulation in the bag. Higher fill power down weighs less and compresses more than lower fill power down. As you might imagine, higher fill power is also more expensive.
In general, 800 fill power and up is considered high quality down. Anything lower than that will be more cost effective, but won’t have as good a warmth-to-weight ratio.
Warm when Wet
Synthetic insulation bags (and, to a lesser degree, bags treated with “dry down”) will technically hold in warmth better than down when wet, and dry quicker. But it’s important to remember that no sleeping bag will be comfortable when wet.
If you end up having to spend the night in a wet sleeping bag, you’re probably going to be miserable any way you slice it. So our advice is not to choose a sleeping bag based on how it will perform when wet. Instead, always remain vigilant to keep your sleeping bag dry at all times.
Bag Length
Check with the manufacturer to find the correct length sleeping bag to fit your height. If you’re on the edge, the longer size will usually be a better fit. With a quilt, consider bumping up one size for the ability to pull it over your head on really chilly nights.
Bag Width
Mummy bags usually come in fairly standard widths, so if the cut is too slim you’ll probably need to choose a different model. Slim cut bags are great for saving weight and efficient warmth, but they do tend to be more restrictive.
Most quilts come with the option of choosing a width. A little extra width in a quilt can be very nice for making sure there are no drafts when shifting around at night. This can be especially helpful if you’re wearing a bulky puffy coat on truly frigid nights.
Zipper Length
Mummy bags often come with different zipper lengths. Full-length zippers are ideal because they give you the ability to open the bag completely for ventilation. Some bags reduce weight by cutting down on zipper length.
If you usually like having your feet tucked in, a shorter zipper might not bother you. But most people prefer the flexibility of full-length zippers.
DWR
Durable water repellent is a treatment that causes water to bead up on the outer shell of a sleeping bag rather than soak in.
DWR will wear off over time and need to be reapplied, but it’s a nice feature to have. It won’t make a bag anywhere near waterproof, but it does add a little extra protection.
Storage
Never store any sleeping bag compressed. Always take it out of its sack and store it in a dry location. Hang your sleeping bag up, or keep it in a large sack with room to spread out.
Storing your sleeping bag while compressed can damage the insulation of your bag and hurt its ability to hold heat over time.
Conclusion
If you are looking at a bag with a very good warmth-to-weight ratio and comfort, our choice would be the Teton Sports Altos Ultralight Mummy Sleeping Bag.
One of the main features we recommend this bag is for the loft quality and the grid baffle design. It has a well thought out design with features such as two-way zippers, DriDown fabric for water resistance and a generous internal dimension.
There you have it. Hopefully now you can drill down to finding the best 0 degree sleeping bag for your next backpacking trip. As usual, if you have any questions feel free to drop by a comment.
