Best Cold-Weather Sleeping Bags of 2023

When the cold weather kicks in, you need some serious insulation to ensure your nights in the tent aren't sleepless ones. Find the best bedtime insulator for your winter, spring, and fall adventures in our guide.

Monica Nigon Avatar
Written by: | Reviewed by: Kieran James Cunningham
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We should start by letting you in on a little secret.

Remember all those times your hardy camping friends were out there being beyond-belief badass by continuing their camping in the dead of winter?

Well, the truth is, there wasn’t much badass about it at all.

Sure, it might seem like you need to be blessed with a special kinda nuttiness/masochism/makeup to carry on your camping when temps start heading south of 30 degrees. In reality, however, all it takes is having a great winter sleeping bag along for the trip.

To help you find that kinda sleeping bag, in this article we’ll provide a detailed guide on what to look for when buying for winter camping along with reviews of our top eight picks for this year.

Top Choices by Category

Budget: Marmot Trestles and Kelty Cosmic 0
Under 3 lbs.: Western Mountaineering Versalite 10, Western Mountaineering Kodiak MF, Nemo Sonic 0, and Feathered Friends Snowbunting EX 0
Fill Power/Fill Weight Ratio: Western Mountaineering Kodiak MF and Mountain Hardwear Phantom 0

Western Mountaineering Kodiak MF

Editor’s Choice

Western Mountaineering Kodiak MF Sleeping Bag: 0 Degree Down One Color, 6ft/Right Zip

The Kodiak MF scoops our Editor’s Choice award for several reasons. It’s lightweight, water-resistant, compressible, has a great warmth-to-weight ratio, and is as comfortable as sleeping bags are made.

The Kodiak’s 30-ounce fill weight and 850-fill down insulation make it a top performer in both the packability and warmth metrics. Unlike many mummy sleeping bags, its ample shoulder, hip, and foot room also make it a comfortable cocoon for all kinds of sleepers (front, back, or side). Its roominess also means you can squeeze in all the gear you need to keep warm overnight.

We are great fans of the Kodiak’s “bonus features,” with the oversized 3D draft tubes, snag-free zippers, plush draft collar, and water-resistant but breathable and silent Microlight XP shell fabric stealing the show.

All of these features come at a price, however, as the Kodiak MF is one of the most expensive sleeping bags for cold weather on our list. Yet if you’re looking for a sack that shines in all metrics, this one deserves a place on your shortlist nonetheless.

Bottom Line: A toasty-warm, comfortable, and lightweight model that trumps the best of the rest in conditions down to 0 °F.

At a Glance: Quick Recommendations

  • Editor’s Choice:  Western Mountaineering Kodiak MF
    “An extra-warm, extra-comfortable winter cocoon that boasts an outstanding warmth-to-weight ratio.”
  • Runner-up:  Mountain Hardwear Phantom 0
    “A sustainably-made model that’s great for lightweight backpackers, the Mountain Hardwear Phantom 0 narrowly misses out to the Kodiak MF due to its lack of hydrophobic down. “
  • Best Lightweight:  Western Mountaineering Versalite 10
    “While not the best bet for extremely cold temps, this is the go-to option for the lightweight fanatics out there and the lightest model that we tested.”
  • Most Comfortable:  NEMO Sonic 0
    “The Sonic 0 wins out for Most Comfortable due to its roominess and stretch construction around the knees.”
  • Best for Extreme Cold:  Marmot CWM
    “With a temperature rating of -40°F, the CWM wins our vote for trips in crazily cold conditions.”
  • Best Budget:  Marmot Trestles Elite Ecco 0
    “The only synthetic model on our list, the Trestles 0 will keep you warm when wet without taking too much of a dent out of your paycheck, but won’t be as warm as down models.”
  • Best Value:  Kelty Cosmic 0
    “While a little on the heavy side, this synthetic bag offers a superb warmth-to-$ ratio.”
  • Best for Wet Conditions:  Feathered Friends Snowbunting EX 0 Sleeping Bag
    “The Snowbunting EX 0 is the go-to for those looking for supreme waterproof capabilities in rainy or wet snow conditions.”

The Best Cold-Weather Sleeping Bags Reviewed

Western Mountaineering Kodiak MF

Editor’s Choice

Weight: 2.85 lbs. ⸱ Fill Weight: 30 oz. ⸱ Fill Power: 850

The Kodiak does everything a hardy wintertime adventurer needs their sleeping bag to do. It’s relatively light, has an outstanding warmth-to-weight ratio, and uses a patented Microlight XP shell fabric that repels water.

The Kodiak is made with 30 ounces of 850-fill goose down. While this means you get a whopping 7 inches of down insulation swaddling of your body, it remains compressible due to the high fill power of the down.

The Kodiak is also one of the roomiest bags on our list. It’s 200cm long, 170cm at the shoulder, and 147cm at the hips. It’s a mummy bag, yet still has a generous, 41-inch foot box. These dimensions make it super-comfortable for side, front, and back sleepers alike. All that extra room also allows you to wear extra layers for staying warm in especially cold winter weather.

Other nice touches include 3D draft tubes to keep your body heat in and cold air out, snag-free zippers, and a full-down neck and shoulder collar that feels extra-soft against the skin.

  • PROs

    • Warm and lightweight
    • Highly packable
    • Water-resistant
    • Enough room for extra layers on extra-chilly nights
  • CONs

    • Expensive bag

Bottom-Line: The Kodiak MF is our favorite winter sleeping bag due to its superb insulation, roominess, and patented water-repellent shell.

Mountain Hardwear Phantom 0

Runner-up

Weight: 2.68 lbs. ⸱ Fill Weight: 29.6 oz. ⸱ Fill Power: 850

The Mountain Hardwear Phantom 0 has been around for years, and in that time it has consistently ranked as one of the best sleeping bags for winter camping out there.

The Phantom 0 boasts similar specs to the Kodiak MF. It weighs just a few ounces less and uses 29.6 oz. of 850-fill down. It also has waterproof-breathable shell fabric and a durable water-repellent finish.

While not as weather-resistant as the Kodiak, the Phantom’s lighter weight and smaller packed size make it a better option for backpacking trips. This is also one of the more sustainable models on our list as it contains recycled materials, namely a 10D nylon shell.

This mummy sleeping bag has a few other things going for it too. In addition to a contoured footbox that allows for a natural foot position and downdraft collar, it has both left and right-hand zippers. These allow both easy entry/exit and let you zip your bag together with your partner’s.

  • PROs

    • Warm
    • Lightweight
    • 10D recycled nylon shell
    • Glow-in-the-dark zipper pulls
    • Interior storage pocket
    • Awesome stuff sack
  • CONs

    • Down is not hydrophobic
    • Hood doesn’t cinch down

Bottom-Line: A great option for those looking for a lightweight model with a snugger fit.

Western Mountaineering Versalite 10

Best Lightweight

Weight: 2 lbs. ⸱ Fill Weight: 20 oz. ⸱ Fill Power: 850+

Winning the award of the best lightweight cold-weather sleeping bag is the impossibly light Western Mountaineering Versalite 10. At just 2 pounds, it beats the other models we tested by a high margin when it comes to weight.

You’ll still get 850+ premium goose-down fill power, meaning it will keep you plenty warm on nights 10 degrees or above. That being said, it has a lesser fill weight than the Kodiak and the Phantom, making it more of a three-season bag (depending, of course, on where you are in the world).

The Versalite has a plethora of value-adding features. The most notable are a handy “Super” Full Collar to seal in extra warmth, extra foot girth for those of us who like to kick around a bit in our sleep, and continuous baffles along its length for superior heat retention.

  • PROs

    • Lightweight
    • Highly packable
    • High fill power
    • Down collar seals in warmth
    • Extra foot girth
  • CONs

    • Not as warm as heftier models
    • Shell isn’t water-resistant

Bottom-Line: The Versalite lacks the warmth of other models on our list, but its light weight and small packed size make it an excellent choice for three-season, ultralight adventurers.

NEMO Sonic 0

Most Comfortable

Weight: 2.95 lbs. ⸱ Fill Weight: 20 oz. ⸱ Fill Power: 800

Hands down the most comfortable cold-weather sleeping bag out there is the Nemo Sonic 0. It’s chock full of features to not only keep you warm but give you a comfortable and cozy night’s sleep on chilly, zero-degree nights.

The Sonic 0 has a contoured hood with a drawstring cord to prevent heat loss from the neck up. Its Toester™ footbox includes an extra layer of synthetic insulation to prevent freezing toes.

But what really makes the Sonic comfortable are the stretch baffles at the knees, which allow for uninhibited movement, and the side vents that permit temperature control. For side sleepers, it doesn’t get much better than this.

The 800-fill goose down used in the Sonic is sustainably sourced and Responsibly Down Standard (RDS) certified. It’s also hydrophobic, so it performs better in damp conditions.

The downsides? In testing, we found the Sonic 0 significantly less warm than other zero-degree-rated bags owing to its lower fill weight and roomier dimensions.

  • PROs

    • Comfortable,
    • Excellent for side sleepers
    • Sustainably made
    • Hydrophobic down
    • Vents for temperature control
  • CONs

    • Not as warm as other models

Bottom-Line: The Sonic 0’s roominess, vents, and stretch construction make it ideal for buyers who value comfort above all else.

Marmot CWM

Best for Extreme Cold

Weight: 4 lbs. 15.5 oz. ⸱ Fill Weight: 47 oz. ⸱ Fill Power: 800+

If you plan on camping in extreme cold, the Marmot CWM is the bag you want to be doing it in.

This beast of a bag has a temperature rating of -40°F, so is good to go virtually anywhere short of the higher portions of Everest or cooler corners of Siberia. It’s made with a 47 oz. of 800+ fill goose down. While this makes it heavier and bulkier than any other bag on our list, its warmth-to-weight ratio is still mightily impressive.

The CWM features a cross-baffle construction and baffled hood to eliminate cold spots and keep out drafts. There’s also a down-filled tube along the zipper to keep warmth from leaking out and a 360-degree foot box.

The CWM also uses a waterproof-breathable Pertex Shield outer shell that makes it ideal for wet weather and extreme alpine environments.

  • PROs

    • Incredibly warm
    • Highly water-resistant shell fabrics
    • 360-degree foot box
    • Temperature rating of -40°F
  • CONs

    • Bulky
    • Heavy
    • Pricey

Bottom-Line: Overkill for most people doing their winter camping in most of the lower 48, but ideal if you’re a cold sleeper or anticipate truly frigid nighttime temperatures. The warmest of all the bags in our review.

Marmot Trestles Elite Ecco 0

Best Budget

Weight: 3 lbs. 8.3 oz. ⸱ Fill Weight: 41 oz. ⸱ Fill Power: N/A

The Marmot Trestles Elite Ecco 0 Sleeping Bag is the only synthetic bag on our list. Thanks to its affordable price and impressive warmth-to-$ ratio, it is our favorite budget sleeping bag for cold-weather adventures.

The Trestles is made with a tough, ripstop polyester shell and 41 ounces of HL-ElixR Eco Micro recycled synthetic fibers. While this will keep you cozy, it’s a bit heavier and less packable than down alternatives, making it a hard sell for ultralight backpackers. On the plus side, the Trestles Elite Ecco performs better than down equivalents in damp conditions.

Other endearing features in this bag include a 3D Footbox that increases the insulation and room for your feet, full-length, anti-snag zippers, and a handy interior stash pocket.

For a bag that costs around the same as your average high-end sleeping pad, that ain’t bad…

  • PROs

    • Sustainably made from recycled products
    • Can be unzipped to turn into a quilt
    • Stays warm when wet
    • Affordable
  • CONs

    • Not as warm as down models
    • Heavy
    • Hard to pack into stuff sack

Bottom-Line: As budget-friendly bags go this is a solid option for buyers keen to get as much bang for their buck as possible.

Kelty Cosmic 0 Sleeping Bag

Best Value

Weight: 4 lb. 9 oz. ⸱ Fill Weight: 40 oz. ⸱ Fill Power: 550

Looking for a sleeping bag that will keep you comfy and cozy without emptying your bank account? Look no further than the Kelty Cosmic 0.

While a bit heavier and less compressible than others, the Cosmic 0 does its primary job of keeping you warm. This means it’s far from optimal for backcountry forays, but a solid option for car camping.

In testing, the Cosmic felt just as warm as many far pricier bags, though we did notice that the DWR treatment struggled to fend off substantial condensation and we weren’t overly impressed with the smaller hood. And while thermally efficient, the bag’s tighter fit means there isn’t much extra room for your down jacket or other outdoor gear inside.

  • PROs

    • Insulative
    • Internal pocket for packing small items
    • Affordable
    • Effective draft collar keeps in body heat
    • Trapezoidal baffles eliminate cold spots
  • CONs

    • Heavier and bulkier than down bags
    • Lacks water resistance compared to other bags

Bottom-Line: While a little heavier and less compressible than other models, the Cosmic 0 is a solid cold-weather sleeping bag for car campers on a tighter budget.

Feathered Friends Snowbunting EX 0 Sleeping Bag

Best for Wet Conditions

Weight: 2 lb. 13 oz. ⸱ Fill Weight: 25.3 oz. ⸱ Fill Power: 900+

If you’re the type who camps in rainy conditions or dense wet snow, look to the Feathered Friends Snowbunting EX 0 Sleeping Bag for superb waterproofness and warmth.

The Snowbunting is equipped with the award-winning Pertex Shield EX, a water-resistant and breathable laminate outer shell treated with DWR. Its collar prevents breath condensation and sweat from dampening your bag, and the contoured hood insulates your head.

The two-way zipper is reinforced with a large draft tube to prevent cold air from seeping in and heat from seeping out.

It compresses well even though there are continuous baffles throughout the bag, which incidentally allows you to puff up the down where you need it.

  • PROs

    • Waterproof
    • Insulative
    • Lightweight
    • Highly water-resistant outer shell
  • CONs

    • A bit restrictive
    • Small hood

Bottom-Line: For outstanding waterproof capabilities and warmth in wet conditions, Snowbunting EX 0 Sleeping Bag should be top of your list.

Buyers Guide to Cold-Weather Sleeping Bags

Insulation: Down vs Synthetic Sleeping Bag

Sleeping bags use two different main types of insulation: down and synthetic

Down sleeping bags, usually made from the plumage of geese or ducks, often have a higher price tag than synthetic. They are much more compressible, taking up less coveted space in your backpack. They’re also durable. With proper care, a down model could last you decades. 

Synthetic bags won’t make as big of a dent in your savings, but that comes at a different kind of cost. They’ll take up more space in your backpack and add at least a few ounces to your pack weight. On the plus side, synthetic insulation will continue to keep you warm even when damp, so is a better performer in wet conditions than regular (non-hydrophobic) down. 

Fill Power and Fill Weight

When it comes to picking a down sleeping bag, keep both fill power and fill weight in mind. Fill power takes into account the quality of the down, while the fill weight indicates how much is used in the bag’s construction.

Man sleeping in down sleeping bag beside snow
The right balance between fill power and fill weight will depend on your individual requirements.

A higher fill power (800-900) will indicate the down is loftier; there are more pockets of warm air trapped between the feathers, which equates to more warmth. Higher fill power also translates into superior compressibility.

However, high-quality down won’t do you any good if there isn’t enough of it. So, be sure to check the fill weight, which will give you a metric of how much down your bag contains. 

A high fill power with low fill weight means the sleeping bag is more compressible but lacks warmth, while a lower fill power with a high fill weight will mean the bag might be warm, but is sure to be bulky and heavy. The name of the game, then, is finding a good balance between fill weight and fill power.

Comfort & Fit

Not only do you want a sleeping bag to keep you cozy on frosty nights, but you also want it to fit you well. To ensure a good fit, you’ll want to research the width and height measurements of the manufacturer, as not all bags are made the same. 

Woman standing in sleeping bag in the snow
Sleeping bags come in a variety of shapes and sizes for all preferences.

Think of a mummy bag that tapers at the feet. It may compress down smaller and weigh less, but if you’re the kind of person who likes to kick their feet around a bit in their sleep, this bag probably isn’t for you. 

On the flip side, a bag that allows you a bit more room may be more comfortable but less efficient at trapping air, and thus a bit less warm. It will also, of course, take up more pack space. 

No matter what style you choose, keep in mind the zipper. Some of them zip all the way to the bottom and can be unfurled to be used as a blanket, while others only unzip halfway, which may feel overly claustrophobic for some. 

Temperature Rating

Brands will usually market their bags with a “season rating” (2-season, 3-season, etc.), but they’re a bit subjective. Luckily, the EN Rating System (European Norm) makes it easy to pick a bag based on their system of four temperature ratings: 

  • Upper Limit: the highest temp where an average-sized man can sleep comfortably without excessive sweating
  • Comfort: the ideal temperature an average-sized woman can comfortably sleep
  • Lower Limit/Comfort Limit: the lowest temperature where an average-sized man can comfortably sleep for up to 8 hours.
  • Extreme Limit: the lowest temp an average-sized woman or cold sleeper can lay without hypothermia for up to 6 hours. 
Thermometer showing minus 30 degrees
The EN rating system classifies sleeping bags into handy temperature categories.

To ensure you get a good night’s sleep on your winter camps, we recommend choosing a new winter bag with a comfort rating of at least 10 degrees below the coldest temps you expect to encounter. 

Size 

If you’re hoping to save space in your backpack for a multi-day mission, it’s imperative to consider a bag that will be lightweight and can compact down to a relatively small size. In this case, a down bag with a high fill power is the way to go. 

If you’re not so worried about space or weight savings but are more concerned about the price tag, then synthetic sleeping bags like the Marmot Trestles, or low-fill bags like the Kelty Cosmic 0, are a better option. 

Weight

In general, cold-weather sleeping bags will weigh between 2.5 and 3.5 lbs., while sub-zero bags can weigh up to 5 lbs. Again, if you’re a casual car camper or just do short backpacking missions, you won’t have to worry about weight as much as a thru-hiker or multi-day adventurer. 

Man walking through the snow carrying camping gear on his back
For the backpacker or thru-hiker, the weight of camping equipment is always high on the priority list.

For ultralight missions, our top pick is the Western Mountaineering Versatile 10, which weighs a piddly 2 lbs. For car camping, heavier bags like the Kelty Cosmic and Marmot CWM become an option. 

Water Resistance

Many bags have a Durable Water Repellent (DWR) treatment on the outer shell. While this doesn’t make it completely waterproof, it will help to keep condensation from seeping through into the insulation, which can seriously impair its ability to insulate – particularly with a down fill. 

Style and Shape

Sleeping bags usually come in regular, long, and women’s sizes. Women’s-specific mummy bags will be generally shorter, slimmer at the shoulders, and wider near the hips. 

Features & Accessories

A few features can seriously enhance a sleeping bag’s practicality and convenience:

  • Hood: Seals in the heat (together with a draft collar)
  • Elasticized Baffles: Allow you to sit cross-legged and give you more space for tossing and turning 
  • Vents: These make the bag more versatile by allowing you to use it in warmer conditions
  • Stash Pocket: Nifty feature that gives you space to store smaller items like a headlamp
  • Zippers: Full-length, dual-direction zippers are better for venting, while glow-in-the-dark tabs will let you locate the zipper with ease at nighttime
  • Foot box: Specially designed to keep your feet warm and with a little extra space for turning
  • Stuff Sack/Compression Sack: All bags come with a stuff storage sack, but those with compression straps will allow you to save more pack space
Woman stuffing sleeping bag into stuff sack in the snow
Extra features, such as compression straps for your stuff sack, really enhance the practical usability of a bag.

Cold-Weather Sleeping Bags: The Verdict

The Western Mountaineering Kodiak MF wins our award for Best Cold-Weather Sleeping Bag Overall due to its supreme warmth, comfort, and water-repelling capabilities.

For a budget option that will keep you warm without the nifty features of the Kodiak, the Kelty Cosmic 0 or the Marmot Trestles 0 are well worth checking out, especially for car campers. And if weight savings and packability are a priority, the Western Mountaineering Versalite 10 is our pick of the bunch.

What did you think of our recommendations? Leave a comment below if you have any questions or if we missed your favorite! 

Last update on 2023-06-01 / Affiliate links / Images from Amazon Product Advertising API

Monica Nigon Avatar

Monica is a freelance writer, ski patroller, and raft guide based out of Colorado, and is passionate about mountain biking, rock climbing, and playing Irish music on her fiddle in her spare time. Growing up in rural Minnesota, she learned how to brave the cold in the pursuit of adventure from an early age.

In the winter you’ll find Monica skiing at her home resort of Wolf Creek, near Pagosa Springs, which she now calls home. In the summer, you’ll find her guiding the Class III-IV whitewater of the Arkansas River nearby. She’s also taught skiing, environmental education, kayaking, and canoeing. 

Her favorite adventures have involved backpacking the Rockies with her best friends and mountain biking the slick rock of the deserts of Utah. Even better are long meanders through the woods and mountains on her backcountry skis. She’s also done irresponsible things internationally like sledding down a volcano in Nicaragua and surfing off the northwest coast of Ireland. 

She holds certifications in avalanche rescue, professional ski instruction, and wilderness medicine. She enjoys reading and writing about all of the above.

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