The Marmot Col is a hulking behemoth of loft and warmth. Possibly the warmest bag in this category, the Col boasts a tough weatherproof shell, vertical baffles to keep the down over your core, and loads of features that make it a good choice for expeditions and long trips where you could be hunkered down in foul weather for extended periods.
Marmot has made a few updates to the Col. Our review reflects the findings of the updated model. November 2022
This bag is a good choice for expeditions in cold environments
For temps down to zero degrees, you can't beat this lightweight but very warm bag
A truly supreme sleeping bag that stands out for impressive weight savings without missing out on warmth
An inexpensive bag that offers excellent warmth and weather resistance, albeit heavier than most in our fleet
Marmot Col -20
Mountain Hardwear P...
Mountain Hardwear B...
Marmot Col -20
Mountain Hardwear P...
Mountain Hardwear B...
Measured Weight (size Regular)
4.5 lbs (used to be 4.08 lbs, so heavier by .42 lbs)
Type of Down Fill
Goose Down RDS Cert/Fluorine Free
Material Weight (excludes down filling)
Pertex Microlite 30 Denier
10D Nylon Ghost ripstop, DWR finish
20-Denier ripstop nylon
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Our Analysis and Test Results
This big burly bag is super spacious and warm, making it ideal for hanging out in base camp while the weather is foul. A newly designed center zipper allows ease of entry and exit, while two side zippers let you use your arms outside the bag. All that space and durability comes at a cost, and the Col is one of the heavier bags in our review.
The Col is packed with 800 fill down, giving it incredible loft and insulative powers and a good warmth-to-weight ratio. While the abundant down between you and the elements keeps most of the cold out, the three zippers and extra space allow a small amount of air to sneak into this new design, even though lofty baffles surround the beefy zippers. The extra space accommodates more layers, along with other stuff you might want to keep from freezing solid, like water and your boots.
When sleeping on your back with the hood completely cinched tight, the air hole is suspended several inches above your face, so you can still breathe without your nose freezing off. A thick draft collar with a dedicated cinch cord keeps out any drafts that make it past the hood. While the three zippers add convenience, they allow more entry points for stubborn, cold air to seep in. Fortunately, baffles adjacent to each zipper trap most of these small amounts of cold air.
The robust shell fabric, wide cut, and amount of down make the Col the second heaviest bag in this review. In a backpack, 4 lbs 8 oz is a lot of sleeping bag to haul around. If you're carrying this bag into the snowy wilds on a sled or snowmobile, the warmth, space, and features easily make up for the extra weight.
4 pounds, 13.7 oz with the compression sack, and 4 pounds, 8.4 oz without it.
The Col gets a pretty solid score for comfort because there is so much room to move around, change clothes, and burrow down inside the bag. This is essential if you spend many hours inside this bag, waiting out bad weather. The Col gains and then loses a few comfort points for the zippers and cinch cords. While the center zipper located on top allows you to enter and exit easily, sit up and easily unzip, the zipper pull was uncomfortably touching our chin while sleeping on our backs. The side zippers let you drink, eat, or read a book, all from the comfort of your sleeping cocoon.
Unfortunately, all these zippers add weight to an already hefty bag and can allow cold air to seep in. Baffles around the zippers block that cold air somewhat, but not entirely. The cinch straps are easy to locate inside the hood, but they're right in your face. Also, there is thick material around the inside of the foot box that some testers didn't like against their feet. This problem is easily mitigated with a down jacket and a pair of socks.
All that down and shell material makes for a relatively large packed size. The Col still holds its own against similarly rated bags. Due to high-quality materials, the Col still manages to pack down small enough in a 60-liter pack to allow room for other winter gear.
This contender is designed for extended winter trips. The features are on point with what our testers who've lived and worked in cold climates like to see. The inside of the foot box is reinforced with a thicker shell fabric to protect the bag from your boots. There is enough room in the foot box to sleep with your boots on or leave them down in the bottom of the bag, so you don't have to thaw your boots out, making it way easier to get up in the morning. Draft tubes prevent most cold air from entering through the zippers, and the zipper configuration allows you to enjoy a hot drink or read a book while keeping most of your upper body inside the bag. The three zippers are also useful for venting if you get too hot in this bag (we sure did).
Two cinch straps, one for the neck baffle and one for the hood, are great for sealing out cold air. The problem is they are too close to your face. There are five internal stow-away pockets, one of which has a zipper and is almost hidden. The zippered pocket is important for not losing important items like headlamps and spare batteries. The non-zippered pockets are perfect for stashing things like gloves and spare socks to dry without moving around while you sleep.
We subjected the Col to rigorous testing by dunking the middle section of it into a bathtub. Now, unless you're planning on swimming while inside this sleeping bag, it's unlikely you'll ever put it through this amount of moisture. In our submersion test, we fully dunked the bag underwater and tried our best to squeeze out all the air so that the bag could absorb as much water as possible. We found that the Col absorbed water, and a lot of it. Most likely, the water snuck in through one of the three closed zippers.
We also tested the Col while it was snowing outside. The snow bounced right off the Pertex Shield Fabric and kept us dry. So, unless you're going swimming in it, that down probably isn't going to get wet. A simple lean-to, lightweight tent or snow cave will block the high winds, and the Col will take most likely take care of the rest. Of course, with a sleeping bag this heavy, you're more likely to be base camping in a burly 4-season winter tent.
Should You Buy the Marmot Col -20?
The Col is designed for cold weather and base camping. The features that facilitate waiting out long periods of chilly weather are the same features that add weight and bulk. If weight isn't an issue, you want a really roomy sleeping bag, and you like the dual side zips for using your arms while still inside a sleeping bag, the Col might be just right for you. However, if you're looking for a lightweight bag with a simple design, then check out some of the other bags in our lineup.
What Other Winter Sleeping Bags Should You Consider?
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