12 of the Best Winter Sleeping Bags for 2018

Whether your travels are taking you to Kilimanjaro or Mount Kenya, to Everest Base Camp or backpacking during the colder months, a good winter sleeping bag is essential. 

Hiking at in the cold or at altitude is hard and after a strenuous day on the trail, getting a good night’s sleep is hard enough, without being cold as well!

We've checked out 12 winter sleeping bags for you to consider for your next mountain adventure.

Winter sleeping bags divide into 0F (-15C) and 15F (-10C) temperature ratings. For super-cold weather, or hiking that involves going over 10,000ft, you'll probably want to go with a 0F bag. 

0F (-15C) Down Sleeping Bags

These are the warmest sleeping bags for their weight but they are the most expensive. You might want to choose one of these if you tend to feel the cold at night and are planning more than just a “one-off” expedition.

Thanks to their superior warmth-to-weight ratio, these are the best sleeping bags if you are planning an unsupported backpacking trek. For sleeping in Kilimanjaro’s crater (Crater Camp) I would highly recommend a 0F rated Down sleeping bag as it’s bone-chillingly cold next to the glacier.

Top Choice: RAB Expedition 100 (this wins on warmth)

Best for Budget: Kelty Cosmic Down

The Nemo Sonic is an extremely comfortable sleeping bag. It's roomy design accommodates side-sleepers and those who are restless at night.

This comes at the expense of warmth. 


If you like to sleep with a few layers of clothing, then the extra room might suit you. Others will find that the compromise in terms of warmth and thermal efficiency is just too much. 


This bag performs a bit more like a 15F bag, rather than a 0F, but it's a good choice if you don't like a very snug-fitting sleeping bag that restricts your movement in the night.


The Nemo Sonic is durable, the weather-resistant DWR coating performs well in damp weather. 


The 850-fill Goose down has a high warmth-to-weight ratio, and it packs down very small in the compression sack included. For such a roomy, comfortable bag, it's very light and small and will not overload your backpack.


What We Like

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    Super-lightweight and packable, taking up little space/weight in your  duffel bag or backpack
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    Durable, ripstop 20 denier shell fabric means you can give this bag some abuse before it falls apart!
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    Roomy size keeps side-sleepers and restless sleepers happy it's nice and wide with a stretchy footbox (so you can even wear your boots to bed!)
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     "Hybrid baffle system" - comprising vertical baffles in the upper part of the bag and horizontal baffles in the footbox means extra warmth where you need it most - apparently. 
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    Two vertical vents prevent you from getting too hot - although I'm wondering why you'd want a 0F bag if you were worried about heat!
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    Internal collar and drawcord ensures that valuable heat will not be lost from your head and neck area.
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    DWR treated shell fabric maintains good water resistance

What We Don't Like

  • Warmth is not really up to the 0F rating - if you are a 'cold' sleeper, this one may not be for you
  • External storage pouch which isn't great as batteries can get a bit cold and drain easier
  • The Down is not treated to be hydrophobic, but the shell fabric is water resistant 

If you are looking for a premium-quality, ultra-lightweight winter sleeping bag that punches well over it’s weight in warmth, then this one’s for you.


It comes at a premium price, but it’s durable and will see you through most of the major hikes at altitude.


Goose down is the has the highest warmth-to-weight ratio of all the sleeping bag fillers. After a tough day’s hiking, you should get a great night’s sleep!


If your trip to Kilimanjaro or Everest Base Camp is a one-off and you are unlikely to use it again, then perhaps you might consider something a little cheaper and less high-spec.


What We Like

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    Super-lightweight and packable, taking up little space/weight in your  duffel bag or backpack
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    Moisture-repellent (hydrophobic) 850 European Goose down filling for a supremely warm night, even when camping in a damp cloud on Kilimanjaro!
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    Pertex Endurance fabrics are supremely durable, and soft to the touch without being heavy 
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    Trapezoid baffle chamber design maintains the ‘loft’ of the down without increasing weight, reducing those annoying cold-spots
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    Waterproof dry-bag compression sack keeps the bag dry when being transported
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    Sleep limit -20C so you’ll be fine even on Aconcagua!
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    Internal collar and close-fitting neck baffle ensures that valuable heat will not be lost from your head and neck area.
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    Anti-snag ¾ length zipper
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    Internal zippered pocket for you to store small items
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    Fluorocarbon-free

What We Don't Like

  • Cost - this is a premium sleeping bag at a premium price - you'll want this if you are planning multiple mountain trips, not just some light winter backpacking

The Kelty Cosmic Down 0 is an excellent winter sleeping bag for it’s price point.


If you are looking for the superior warmth and packability of Down without the hefty price tag, then you should give this one your serious consideration.


It’s a good all round sleeping bag that will keep you warm and comfortable. Available in a regular and a long length for maximum comfort whatever your height.


Being an entry-level sleeping bag, it is heavier than the more premium down sleeping bags but for the price, it’s a great buy.


What We Like

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    Cost – excellent 0 degree down sleeping bag for an affordable price
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    600-fill moisture-repellent DriDown keeps you very warm and cosy
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    Durable, rip-stop polyester outer for rugged mountain use
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    Polyester taffeta lining for extra comfort - a very cosy feeling inside this bag
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    Dual sliding, locking zip (with anti-snag), so it's easy to get out of even in the dark
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    Thermal comfort hood and anti-draft collar preventing heat loss from head/neck
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    Quilt-through construction keeps the down in place, reducing cold spots
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    Comfortable, roomy footbox for your hot water bottle
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    Comes in regular and long lengths

What We Don't Like

  • No internal pocket for those little electronic bits and bobs
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    Stuff sack difficult and not waterproof - I'd buy a different one
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    Zip can get stuck, you need to take a bit of care especially with gloves on

OF (15C) Synthetic Sleeping Bags

Synthetic sleeping bags have come a long way since the old bulky, heavy rectangular offerings. If you have an allergy to Down, or simply don’t want to spend the money, then check out these synthetic winter sleeping bags.

Synthetic sleeping bags generally pack a bit bigger than their down counterparts, and weigh a bit more. This is of little concern unless you are planning an unsupported multi-day backpacking trip.

Another advantage of synthetic over down is that it dries a lot quicker and is much more forgiving in wet conditions.

Top Pick: Hyperlamina Torch 0

Best for Budget: Mountain Hardwear Hotbed (not as low-cost but much better value than the Coleman)

The Mountain Hardwear Hyperlamina Torch is a top-class, premium-quality synthetic sleeping bag.


It is very lightweight, barely weighing more than the heavier down bags.


This bag is suitable for both supported treks and unsupported backpacking in rugged, cold environments.


Quick-drying with a windproof outer, this bag is versatile, durable and will withstand most mountain conditions.


If condensation in your tent makes it damp, it will dry in no time and continue to keep you warm.


What We Like

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    200g Thermal-Q insulation which provides a great ‘loft’ and warmth
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    Wind-resistant outer shell which is lightweight and soft.
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    Welded “Lamina” construction eliminates cold spots from stitching
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     Tailored hood blocks drafts and seals in the heat
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    Comfortable footbox with extra insulation so that your feet are always warm
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    Snug fit maximises the efficiency of the insulation keeping you warm
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    Short, central zipper (with baffle) prevents heat loss from the zip area and is easier for side-sleepers
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    Very lightweight – excellent warmth-to-weight ratio
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    Compression stuff-sack included so that it takes up less room in your backpack

What We Don't Like

  • Stuff sack is not waterproof
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    Definitely bulkier than down taking up more room in your backpack
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    Whilst we liked the central zip, it's not to everyone's taste

Mountain Hardwear are an established company and their equipment is high-quality. If you are looking for a great value, lightweight synthetic sleeping bag, this one is a worthy contender.


The more “roomy” shape of this bag maybe more comfortable if you tend to move around a lot in the night or are a side-sleeper.


This bag is also suitable if you are a larger-framed person and you tend to feel restricted in some of the smaller sleeping bags.


The overall look and feel of this bag is durable, warm and functional. If you tend to be a cold sleeper you may like to take along a good sleeping bag liner, just to be sure.


It's not the lightest or the most compressible sleeping bag, but at this price point, it's a solid choice.


What We Like

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    A roomy “comfort mummy shape” which is great if you don’t like to feel restricted
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    Cost
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    Vertical laminated construction eliminates cold spots and maintains the 'loft' of the insulation
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     Double slider, full-length zipper with draft tube stops cold air coming in
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    The hood is well designed to prevent heat escaping keeping your neck and  head warm
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    Adjustable draw-cords so that you can vary the head and chest closure
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    Durable 75 denier outer material which can take some abuse. 
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    Fleece-lined stuff sack that you can use as a pillow
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    Compression stuff-sack included so that it takes up less room in your backpack

What We Don't Like

  • Stuff sack is not waterproof
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    The roomy design whilst comfortable, can compromise warmth if you are small-framed
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    No internal pocket
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    Slightly sticky Zipper, that got caught on the shell fabric

The Coleman bag is a budget winter sleeping bag. It’s versatile, comfortable and will keep you warm and dry on the trail.


If you are wanting to purchase a synthetic bag without the premium price tag but with the warmth and quality that you need this one will do it.


That it’s bigger than the super-lightweight bags should be fine for any supported trek, or car camping.


If you are backpacking, then you'll want something lighter and more compressible. This one is bulky and fairly heavy.


For your Kilimanjaro, Mt Kenya, Everest Base Camp or Machu Picchu needs, this bag is a solid choice. If you tend to sleep a bit cold, I would highly recommend you take a good quality sleeping bag liner along.


What We Like

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    Price
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    Hollow polyester insulation provides good heat retention keeping you warm all night 
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     Full-length, 2-way zipper has a good draft tube to stop cold air coming in
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    The hood is adjustable and roomy, with a comfortable quilted construction
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    Offset quilt construction prevents cold spots  

What We Don't Like

  • Horrible color
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    I wouldn't rely on it on the coldest of cold nights, but coupled with a good liner, it should perform quite well
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    It's bulky and heavy - good for car camping but not for lightweight backpacking

15F (-10C) Down Sleeping Bags

It’s perfectly possible to have a comfortable night’s sleep with a good 15F rated sleeping bag. For most winter backpacking at home, this should be sufficient.

Depending on where you are going, if your trek has you sleeping in lodges (Everest Base Camp) or huts (Marangu Route, Kilimanjaro) then you might not necessarily need the 0F rated bag. This is entirely a personal choice.

If you tend to sleep “cold” at home, when you are not exhausted from 7 hours on the trail then I would suggest you opt for the warmer bag, rated 0F.

If you do decide to take the 15F rated sleeping bag, then I highly recommend a good sleeping bag liner if you are headed to higher elevations, where the nights are bitterly cold and the altitude is affecting you.

When choosing whether to take a 15F bag, do bear in mind that altitude and exertion can both conspire to make you much colder than you would be normally.

Note: if you plan to camp at Crater Camp, Kilimanjaro – I highly recommend a 0F rated bag.

Top Pick: RAB Ascent 700

Best for Budget: Outdoor Vitals Atlas

As usual, RAB knocks it out of the park with the quality of workmanship that goes into their products.


This mid-weight down sleeping bag is a great choice for a 15 degree bag.


Light enough for backpacking, this bag packs down very small. Coupling it with a good sleeping bag liner would likely improve it’s rating to nearer 0F.


The RAB Ascent 700 is a great bag for winter backpacking or a trek like Kilimanjaro, at a great price point for the quality. 


More expensive than a synthetic bag or other, more entry-level down bags but you’ll notice the different as the mercury starts to fall.


What We Like

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    Lightweight and packable, taking up less space and weight in your backpack
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    Moisture-repellent, quick-drying 650 fill power European Duck down filling keeping you warm through the night, maintaining insulation even if you are in damp conditions
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    Soft to the touch and durable Pertex Microlight fabrics make up the outer and inner shell
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    Trapezoid baffle design ensures a stable structure of down in the bag, improving the ‘loft’ to minimize cold spots
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    Internal collar and drawcord ensures that valuable heat will not be lost from your head and neck area.
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    Anti-snag ¾ length zipper
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    Internal zippered pocket for storing your small items
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    Roomy enough design to allow for different sleeping positions
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    Fluorocarbon free

What We Don't Like

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    Cost

This is a good quality, rugged down sleeping bag manufactured from good quality fabric that will keep you warm when the temperature drops.


The treated down does a good job of keeping it’s loft and insulation even in slightly damp conditions.


It packs down small and light, and will not take up too much room in your rucksack or duffel bag.


It’s ideal for unsupported as well as supported treks. The Mountain Hardwear Ratio is a solid sleeping bag for the price point.


What We Like

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    650-fill Down has an advanced “Q.Shield” treatment repelling moisture and maintaining the loft even in damp conditions meaning you don’t freeze when there is a bit of condensation
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    Lightweight water-resistant outer shell which is durable and soft
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    “Thermo Trap” baffle design keeps the down in small compartments maintaining it’s loft and minimizing cold spots around your body
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    Clever face gasket blocks drafts and seals in the heat around your head
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    Comfort fit so that you can sleep in different positions
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    ¾ length anti-snag zipper that works well even with gloves on
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    Very lightweight – excellent warmth-to-weight ratio, compressing down nice and small to take up little room in your backpack

What We Don't Like

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    No waterproof stuff sack
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    Zipper can get stuck if you try to open/close it too fast

Bearing in mind the price point. This bag is a budget down sleeping bag that performs well.


The down is not treated so keeping it dry is very important, although the outer shell material is water-resistant.


It’s not a premium bag with premium features, but if you are budget-conscious then this could be the bag for you.


I would recommend taking a sleeping bag liner to improve it’s warmth.

The bag compresses very small and is lightweight.


It has a rugged and durable feel, with a good zipper. For the price, this is a great sleeping bag.


What We Like

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    Cost
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    Lightweight 500-fill down which has a good warmth-to-weight ratio great for backpacking
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    Drawstrings so that you can adjust the hood keeping your head and neck warm
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    Baffles around neck for keeping the heat in
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    Inside pocket for keeping small items close by
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    Reinforced material around the zipper keeps drafts out
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    Nylon moisture-repellent shell keeps damp away from the down filling
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    Soft and comfortable polyester lining
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    Compresses very small to take up very little room in your duffel or backpack

What We Don't Like

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    Down is not treated to make it moisture repellent
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    Compression sack is not waterproof
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    Down can tend to migrate, leaving cold spots

15F (-10C) Synthetic Sleeping Bags

Slightly heavier and bulkier than their down counterparts, synthetic sleeping bags are an excellent choice for those allergic to down or for travels in wet conditions.

Synthetic sleeping bags perform much better than down when they get wet and are less expensive. For supported treks, when space and weight is not crucial, then a synthetic sleeping bag is an excellent choice.

If space and weight is at a premium, then down will out-perform synthetic insulation every time.

Top Pick: Mountain Hardwear Lamina Z

Best for Budget:  Coleman North Rim (do me a favor, only buy this one if you are on a serious budget and cannot afford anything better. It'll do, but only just!)

The Lamina Z Torch is a lightweight, compressible synthetic sleeping bag that keeps you very warm in winter conditions.


Being synthetic means it will dry quickly if it gets wet, the Lamina design keeps the insulation well ‘lofted’ providing superior warmth at a good price point.


The interior is soft and whilst there is room to move around, you will be toasty warm on winter nights.


Without the extra expense of a down sleeping bag, this one will perform well in damp conditions.


What We Like

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    Cost
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    Thermal Q 200g insulation compresses into a small space taking up little room
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    Lamina construction seals the insulation into the bag without stitching prevents the heat from escaping through the stitched areas eliminating cold spots
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    Extra insulation in the core and foot area keeping you warmer
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    Comfort mummy design allows you to move around without compromising thermal efficiency
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    Soft polyester lining, wicks away moisture from your body
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    Moisture-repellent, durable “ripstop” nylon shell keeps the bag dry
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    Zip pocket for keeping small items close to you
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    Footbox allows you to keep a natural position of your feet without feeling restricted
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    Tailored hood with a face gasket so that you lose less heat from your head and neck
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    Compression stuff sack to pack it down very small

What We Don't Like

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    Compression sack is not waterproof
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    Zippers can be a bit sticky
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    Runs on the short side so consider getting the long version if you are quite tall

This Marmot Trestles 15F sleeping bag is an excellent choice for the price point. A good all-purpose sleeping bag that will keep you warm on various hikes.


Coupled with a good thermal sleeping bag liner this bag is super-warm.


For very high elevations or if you tend to sleep cold, then you might find that this bag isn’t as warm as the more premium-priced synthetic bags.


Marmot makes good quality at a good price. The bag compresses down into a small space (although we don’t like the stuff sack it comes with) and is not too heavy, even if you are doing an unsupported hike.


What We Like

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    Cost
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    SpriaFil high-loft insulation which is constructed in a wave design to keep you warm and eliminate cold spots
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    Insulated hood and collar with drawcords so that you don’t lose heat from your head and neck
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    Footbox that allows a comfortable, natural foot position so that you don’t feel restricted
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    Regular and long sizing: “Long” fit is also extra-wide accommodating folk with larger shoulders or those of us who like a slightly roomier sleeping bag
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    Anti-snag zipper with a draft tube to prevent heat escaping through the zipper
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    Keeps warm even in wet conditions
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    Internal pocket so that you can keep small items close to you
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    Comfortable polyester taffeta lining for extra comfort and durability

What We Don't Like

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    Warmth – a sleeping bag liner is recommended for high elevations
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    Stuff sack not waterproof and not a true “compression” sack
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    Zipper seems to be a bit lightweight and can break

The reason I am mentioning this sleeping bag here is if you are on a seriously low budget, and are only going to use the bag once or twice.


The Coleman North Rim is a budget synthetic sleeping bag that does not pack down well and is heavy.


However, for a supported one-off trek or car camping it’s worth considering if you are concerned about the cost of better sleeping bags. I have seen this sleeping bag on Kilimanjaro and on an Everest Base Camp trek.


It would not be suitable for unsupported backpacking as it’s simply too heavy and bulky. For the price, you are getting a warm sleeping bag, but don’t expect the zippers to last or for it to be very durable.


I would recommend this only if you are on a tight budget and do not wish to rent a sleeping bag from a tour operator.


Choosing Winter Sleeping Bags

"Seasons" & Temperature Rating

Most sleeping bags will have a temperature (warmth rating) often using the “European Norm” system. Additionally they are divided into “Seasons”:

  • 1-Season: Summer, warm-weather use only. Ideal for temperatures above 10C
  • 2-Season: Cooler nights, but still for mild weather use
  • 3-Season: A good all round sleeping bag that would see you through most except the harsh winter nights. You wouldn’t want to try and sleep in the snow or frosty nights.
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    4-Season: Actual winter sleeping bags.

The 1 and 2 season sleeping bags don’t leave much room for error. Even in the summer if you have a cold snap or start feeling somewhat under the weather, these can be left lacking quickly.

The most versatile sleeping bag for most backpacking/camping excursions would be the three season bag. If it’s hot, you can unzip it but it’s got the capacity to keep you warm if the temperature drops.

Even during the summer, if you intend to sleep above 10,000ft you’ll need a winter sleeping bag. All multi-day hikes at altitude mean freezing cold nights. Additionally, the more fatigued you get, the colder you will feel.

I recommend a winter sleeping bag with a temperature rating of 0F (-15C) or 15F (-10C).

However, with a sleeping bag rated 15F (-10C) it is advisable to take a good sleeping bag liner, to keep you comfortable on freezing mountain nights.

A Note About EN Ratings

Note that warmth ratings are not to be relied on exclusively. The EN ratings (European Norm) are often inaccurate. The reason is that they are based on what the “average” person finds comfortable or otherwise.

They are an attempt to standardise the conversion from an insulation value to a temperature range. But they do not take into account that there are many variables that contribute to how comfortable someone is when camping.

- as with most things, you get what you pay for. That’s not to say that the most expensive winter sleeping bag is necessarily the warmest.

How the EN System Works

Don’t rely on it, especially in the “extreme” cases. Use it as a guide only.

The three “standard” ranges are:

  • Comfort limit: This is the temperature range where the “standard”, or “average” woman sleeps comfortably. (You can see that this opens up a huge chasm of what ‘standard’ and ‘average’ entails). At this limit, you should not be feeling cold.
  • Lower limit: At this range, a “standard” or “average” man would be able to sleep comfortably. Once again, what the heck is a “standard man”?
  • Extreme rating: A strong sensation of cold is to be expected here, but in theory this is the minimum temperature that an average woman could endure in this sleeping back for about 6 hours without getting hypothermia. Do not rely on the sleeping bag at this temperature!

You may see an “Upper Limit” rating - this refers to the temperature that an “average” man can sleep without sweating too much. A pretty useless piece of information in my opinion.

The problem with these temperature ratings, apart from the definitions involved in “standard”/”average” people, is that they also take no account of any other factors in your sleep system.

Apart from the fact that people feel the cold differently, the outside conditions: wind, humidity also play a part, as well as the fit of your sleeping bag and whether you are using a sleeping pad are all factors in how well your sleeping bag will perform.

Overall, I take these ratings with a pinch of salt. Always prepare for colder temperatures than you are expecting. It’s easier to peel off and unzip the bag if you are a bit hot, but getting caught on a very cold night can be serious.

Most winter sleeping bags will state that they are 15F or 0F - although as we’ve seen, there are a number of variations within these ratings.

Whether you choose to buy a 15F or a 0F will depend on (a) your budget (b) your expectation of future usage (c) how cold or warm you tend to be at night.

If you are planning multiple treks at altitude, you may like to consider a 0F, but if it’s a one-off trip to Everest Base Camp or Kilimanjaro, then you could easily get away with a 15F.

Shape, Style & Size 

Most modern winter sleeping bags are a “Mummy” shape - looking a little bit like a sarcophagus. This design traps the heat next to your body, minimizing heat loss from the bag so that you stay warmer through the night.

This shape also means the bag is less bulky for fitting into your duffel bag or backpack without compromising on warmth.

Mummy-style sleeping bags have a hood that can be secured around your head and a neck collar that prevents heat loss from your head and neck area.

The narrower the hip/shoulder specifications, the more heat is retained in the sleeping bag. This can be at the expense of comfort, as you may not like the feeling of being restricted.

If you are a restless sleeper, or like to sleep wearing a few layers, opting for a slightly larger (therefore slightly less thermally efficient) bag may keep you more comfortable through the night. 

You want to make sure that the sleeping bag you choose will actually fit. If you are 6’5” you don’t want to be buying a petite sleeping bag.

Most high-end bags will come in a couple of different lengths, so if you are on the tall side, or want room in the footbox for a hot water bottle, be sure to size up.

Be aware that larger sizes (obviously) add weight and volume, an important consideration when backpacking. 

Women’s specific bags are often a slightly different cut from men’s/unisex, and sometimes have more insulation in targeted areas such as footbox and core. The colors make an attempt at being more girly, but overall, I haven't found much difference in terms of performance.

Fill/Insulation

Winter sleeping bags use either down (duck/goose) or synthetic insulation, some a combination of the two.

Down filled bags are significantly more expensive, they hate getting wet and dry slowly. However, they have an extremely good warmth-to-weight ratio keeping you very warm on cold mountain nights.

Down also compresses very small and is super-light, minimizing the amount of weight and space taken up in your backpack.

If you are going on an unsupported backpacking trip where space and weight is at a premium, then Down fill is superior to synthetic.

Goose down is superior to Duck down in terms of its compressibility and warmth-to-weight ratio, though for most of us, we won't notice the difference between a premium quality duck-down sleeping bag and one filled with goose down.

Fill Power

For down sleeping bags, “fill power” is the amount of loft - or volume - any given weight of down produces. So an ounce of 800 fill down will produce more loft (more trapped air - and more warmth) than an ounce of 600 fill down.

The lower the fill power, the more weight is required to produce similar amounts of warmth.

Hydrophobic down: down that is treated with a polymer to make it somewhat water resistant. Hydrophobic down is not waterproof, but it dries quicker and the feathers don’t clump together so quickly. For the tiny bit of extra weight it adds, it is well worth it.

Synthetic filled bags are bulkier as they doesn’t compress as much, and can be heavier. However they are cheaper, better for wet conditions, maintaining their thermal efficiency and drying quickly. This gives you the peace of mind that you’ll still be warm even if it does get wet.

Often recommended for the treks that require camping, such as Kilimanjaro (except Marangu route), Mt Kenya, and the Annapurna circuits, as there is more risk of getting wet, and often on these treks, someone else is carrying your gear.

All that being said, I always use a down winter sleeping bag, even when camping! On camping trips I just be very sure to keep it well stowed in a waterproof stuff-sack. And I avoid sleeping in leaky tents.

Weight & Compressibility

A major consideration is always going to be weight and compressibility. If you are carrying your own gear, you’ll want a sleeping bag that packs down into the smallest size possible and weighs as little as possible.

 If you are on a supported trek and have porters or yaks carrying your kit then you can afford to be less concerned with weight. 

Down comes up trumps in both the weight and the compressibility stakes. Quite apart from being the warmest - it’s warmth to weight and warmth-to-volume ratio is unsurpassed.

The cut of the sleeping bag can also have an effect on it’s compressibility, the mummy shaped bags with their tapered cut tend to compress down smaller than the rectangular ones.

Tip: if your bag doesn’t come with a compression sack, then get yourself a good waterproof one. It will keep the bag dry in your backpack and compress it as small as possible. 

The shell material fabric will contribute to the overall weight, and this will be a trade off between weight and durability.

If you want it all - you want a down sleeping bag!

Weather Resistance and Durability

Whilst the bag won’t be waterproof, it’s important that it can withstand a bit of condensation - at the very least. A decent shell fabric with a DWR treatment should be adequate for all but the worst of leaking tents and downpours.

The more robust the shell material, the heavier it’s likely to be. These days it’s possible to get very durable high-tech shell materials that are super-light, but they’ll cost you more money.

Other Considerations

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    Hood: 

    Since a lot of heat is lost through your head, having a good hood on the bag is important. If you tend to move around when you sleep, you’ll want one that’s a bit roomier, so that you can turn your head to the side. Personally I like a deep, wide hood - not one that I have to cinch up tight.

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    Neck Baffle: 

    Lying in a drafty tent with cold air circulating around your neck is not a pleasant way to spend a night. The neck baffle, or draft collar should fit around your neck, under your chin, giving you extra insulation against heat loss.

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    Pockets: 

    Many sleeping bags have small stash pockets for keeping phones close at hand. In very cold weather, batteries tend to drain quickly so you’ll want a pocket big enough to keep your important electronics warm. Make sure the pocket is accessible and not uncomfortable when full. 

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    Foot Box: 

    I can’t stand a tight foot box. I know it’s more thermally efficient, but having a bit of room in there to put a Nalgene bottle filled with hot water and be able to move around is more important to me. Some bags have reinforced fabric in the foot box, which protects the bag if you do decide to wear your boots to bed.

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    Zippers: 

    You definitely want zippers that do not catch and snag on the shell material. Look for a lining on either side of the zipper and a decent draft tube (an insulated tube running along the inside of the zipper) to prevent heat loss and air getting in. It’s still important to zip and unzip your bag carefully, as rough treatment will tear the shell fabric.

What About Your Sleeping Pad? (Hint: it matters)

A sleeping bag can only do so much. If you have a rubbishy sleeping pad - or worse still, insist on sleeping on ground or on some old foam cushion you dug out of your garage  - don’t expect the sleeping bag to perform at it’s best.

When backpacking in winter, do make sure that you take a decent sleeping pad, with a high R value - it will make all the difference to your comfort and how well your sleeping bag is able to keep you warm. 

Getting the Most Out of Your Sleeping Bag

Top Tips for a good night's sleep on the mountain:

Whether you are camping on Kilimanjaro or Mt Kenya, or sleeping in huts and lodges on your way to Everest Base Camp, here are our top tips for getting the most out of your winter sleeping bag:

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    Keep it dry - if it doesn’t come with a waterproof stuff sack, get one, or wrap it in large heavy-duty garbage bags.
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    Shake out the sleeping bag before you get into it. Having been compressed, you need to get the air back into the fill in order for the ‘loft’ to trap the heat in.
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    Use a sleeping bag liner. I wouldn’t go anywhere without my sleeping bag liner. It keeps your bag clean. Dirt and fine sand from the trail can get into the insulation of the sleeping bag and degrade it. Using a liner will reduce the amount of laundering that your bag will need, prolonging it's life.
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    Also, a decent liner can improve the temperature rating of your bag. If you are in any doubt about whether your sleeping bag will be warm enough, you might want to get hold of a liner to be sure.
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    Keep it clean: if you are not using a liner, then it’s best to have a set of clothes that you only wear at night, minimizes body oils, sweat and dirt accumulating in the bag.
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    At bedtime, fill a water bottle with warm water (make sure it’s watertight!) and stow this in the foot box to keep your toes nice and warm. You can also use chemical warmers in the same way. A good quality Nalgene bottle works well.
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    Before retiring, drink a hot drink to warm your core and walk around a little to get the blood flowing.
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    If you are camping, make sure the sleeping bag is placed away from the side of the tent. Sometimes condensation can form on the sides, wetting the sleeping bag.
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    Use the clothes you plan to wear for the next day’s hike (so long as they are dry) as a pillow, so that they are nice and warm for when you need to put them on.


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