The Highest Warmth-to-Weight Ratio Ultralight Down Pants For Backpacking
When freezing temps are expected, you should pack a pair of the best down pants for backpacking. Ultralight down pants are oft overlooked, and the warmth they contribute cannot be replicated by fleece or merino. You are only as comfortable as your coldest body part, and you will be much happier with toasty legs.
This is a data-informed buyer’s guide! Our ultimate truth for assessing the performance of down pants is the “Uncompressed Down Volume Per Ounce of Total Garment Weight” statistic. This measurement allows us to compare the relative warmth-to-weight ratio of two pairs of pants, and it is derived by multiplying fill power times fill weight, divided by total garment weight. It quantifies how effectively each pair is using its mass to insulate.
You may also be interested in our guide to merino leggings, down jackets, down parkas, down vests, synthetic puffy jackets, down booties, and fleece pants.
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Quick Picks For The Best Down Pants for Backpacking
Ultralight Down Pants
- Editor’s Choice & Best Value: Enlightened Equipment Torrid (not down)
- The Best Seller: Mountain Hardwear Ghost Whisperer Pants
- Top Pick, Stats: Cumulus Basic Down Pants
- Top Pick, Stats: Montbell Light Down Pants
- Top Pick, Lightest: Western Mountaineering Flash Pants
- Top Pick, Durability: Kuiu Super Down LT Puffer Pants
- Top Pick, Ski Touring: Stellar Equipment UL 2.0
Winter Down Pants
- Best Full-Zip: Feathered Friends Helios Pants
- Best Warmth-to-Weight: Rab Argon Pants
- Best On Snow: Western Mountaineering Flight Pants
- Best Expedition-Grade: Feathered Friends Volant Pants
Custom Ultralight Down Pants
- Alan’s Pick: GooseFeet Gear Custom Down Pants
Best Down Pants Comparison Table
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| Model | Price ($) | Weight (oz) | Fill Power (in³/oz) | Fill Weight (oz) | Down Volume (in³) |
Down Volume / Garment Weight (in³/oz)
|
| MH Ghost Whisperer | 295 | 9.0 | 800 | 2.2 | 1760 | 195 |
| Kuiu Super Down LT | 269 | 8.3 | 850 | 1.9 | 1615 | 195 |
| Stellar UL 2.0 | 299 | 7.6 | 850 | 2.1 | 1785 | 234 |
| Western Mountaineering Flash | 375 | 6.5 | 850 | 2.0 | 1700 | 261 |
| Western Mountaineering Flight | 375 | 12.5 | 850 | 4.0 | 3400 | 272 |
| Feathered Friends Volant | 349 | 17.0 | 900 | 5.6 | 5040 | 296 |
| Feathered Friends Helios | 289 | 13.0 | 900 | 4.4 | 3960 | 304 |
| Montbell Light Down Pants | 230 | 6.8 | 800 | 2.8 | 2240 | 315 |
| Rab Argon Pants | 220 | 13.2 | 800 | 5.6 | 4480 | 339 |
| Cumulus Basic | 275* | 7.2 | 850 | 3.6 | 3060 | 425 |
| Enlightened Equipment Torrid | 140 | 6.2 | n/a | n/a | n/a | n/a |
* MSRP of $205. We estimate $260 after tariffs and delivery fees
Ultralight Down Pants & Ultralight Puffy Pants
Enlightened Equipment Torrid Pants
Even though this is a round-up for down pants, our top pick is actually a pair of synthetic insulated puffy pants that outperforms most of the down options while costing way less. Enlightened Equipment Torrid Pants are the lightest model on this list, the most versatile, and the most affordable.
- Price: $140
- Weight: 6.2 oz
- Fabric: 10D Nylon
- Insulation: ClimaShield Apex
- Pros: Ultralight. Top tier synthetic insulation. High warmth-to-weight. Great value. Dries quickly. Warm when wet.
- Cons: Less compressible than down. Lower rise than is desirable.
Features
Much like the corresponding jackets, Enlightened Equipment Torrid Pants put Climashield Apex insulation to great effect as an ultralight synthetic insulator for an incredible price and with a very high warmth-to-weight ratio. It is lofty, quick-drying, water-resistant, and warm when wet. In our experience, it performs at least as well many of the top tier name brand offerings like PrimaLoft Gold.
Unlike jackets where down is usually preferred, we’re much more tolerant of synthetic insulated pants. This is because pants are more likely to get wet or dirty as you interact with nature, and synthetic insulation holds up to both of those better than down.
And while not the warmest insulating pants, we feel that they’re an excellent shoulder season option. As far as features go, these are utterly minimalist. There is a cinch to keep them tight around your waste, and that’s basically it.
Verdict
The Torrid Pants weigh just over six ounces, which make them an incredible value for only $140. Pick up a pair and your legs will thank you next time the temps drop to freezing or a bit below.
Mountain Hardwear Ghost Whisperer Down Pants
Coming in at just under 10 oz, the Mountain Hardwear Ghost Whisperer are perhaps the most widely distributed pair of lightweight down pants, and the model to which all others are compared (often favorably).
- Price: $295
- Weight: 9.0 oz
- Fabric: 15D Nylon
- Fill Power: 800 | Fill Weight: 2.2
- Percent Down Weight: 24%
- Uncompressed Down Volume: 1760
- Down Volume/Jacket Weight: 196 in3/oz
- Pros: Ultralight. Widely available. Hand pockets. Recycled fabric. Good looking.
- Cons: Modest warmth-to-weight. Ankle zips add weight and cost.
Features
While they’re about as cool looking as down pants get, they miss the mark slightly on warmth-to-weight ratio thanks to mid-tier quality down fill, not enough of it, and too many other features.
Ghost Whisperer Pants have 2.2 oz of 800 fp down, they are 77% material weight, 23% down weight, which is notably sub-par. At least 30% down weight is to be expected in expensive down garments. Ergo, these aren’t the warmest or lightest down pants out there.
We also want to call out the tall ankle zippers, which extend almost to the knee. This is a nice gesture, because people with small to medium sized feet will be able to put them on or take them off without removing their shoes. People with big feet may be S.O.L. though.
Verdict
Even if they’re not statistical superior in our round-up, Mountain Hardwear Ghost Whisperer Pants are still lighter than average compared to similar offerings from other mainstream brands, and are still much warmer and more effective than fleece pants or merino tights. Plus, they come in a wide array of color and sizes with fits for women and men.
Western Mountaineering Flash Pants
An ultralight classic! The Western Mountaineering Flash Pants are a go-to pair of ultralight down pants for cold weather camping when temps drop to freezing. They weigh only 6.5 oz, and are filled with two oz of 850 fp down, 31% of the garment’s total weight.
- Price: $375
- Weight: 6.5 oz
- Fabric: 10D* nylon ripstop (*estimate)
- Fill Power: 850 | Fill Weight: 2.0 oz
- Percent Down Weight: 31%
- Uncompressed Down Volume: 1700 in3
- Down Volume/Jacket Weight: 261 in3/oz
- Pros: Ultralight. High warmth-to-weight ratio. Reinforced seat.
- Cons: Lower total warmth than average down pants. Expensive.
Features
These are some seriously packable duds. Thanks to the minimalist design and high quality materials, they compress down to about half a liter. Features include an adjustable belt, elastic ankle closures, and a reinforced seat fabric to prevent tears and snags.
For most trips during the warmer half of each shoulder season, Flash Pants are the perfect ultralight leg insulators for the job. They significantly outperform fleece pants or merino tights in terms of total weight and warmth-to-weight.
However, with only two ounces of down, they’re a titch underfilled and have a lower than average total warmth as down pants go. Enough for cold three season use, but we would recommend a more insulated pair if you’re expecting temps to drop into the 20s or below.
Verdict
All in all, the Western Mountaineering Flash are a well rounded pair of ultralight down pants with enough insulation to get the job done nicely, while still prioritizing weight savings.
Cumulus Basic Down Pants
Cumulus Basic Down Pants have the best warmth-to-weight stats of any model in our guide, but ordering them in America is snarled by tariffs and courier fees.
- Price: $275 (our estimate after fees) $205 MSRP
- Weight: 7.2 oz
- Fabric: 7D Pertex Quantum nylon ripstop
- Fill Power: 850 | Fill Weight: 3.6 oz
- Percent Down Weight: 50%
- Uncompressed Down Volume: 3060 in³
- Down Volume/Jacket Weight: 425 in³/oz
- Pros: Ultralight. Highest warmth-to-weight ratio. Generously filled. Great stats. Ultralight fabric.
- Cons: Tariffs and courier fee-upon-delivery. Delicate fabric. Slow shipping.
Construction & Features
You just can’t argue with the efficiency of 3.6 ounces of 850 fp down in a 7.2 oz pair of pants. They’re literally 50% down and yield the highest warmth-to-weight ratio in the genre. Impressive!
But another contributing factor is the use of 7d shell fabric, lighter than all the rest, but less durable. 7D is about as thin as we’re willing to go for pants, which are exposed to more abrasion than jackets. Features wise, you get a drawcord waist and elasticized cuffs, perfectly minimalist.
Buyer beware: These pants made in and shipped from Poland. While the MSRP is incredibly generous, American buyers will have to pay $20 for international shipping, plus a 15% important tariff in addition to unspecified courier customs fee, paid upon delivery. This isn’t Cumulus’ fault, but it’s worth calling out.
Verdict
The combination of 7d fabric, and generous 850 fill makes these the best choice for gear optimizers who are willing to deal with tariffs, customs, courier fees, and a slower delivery timeline.
Montbell Light Down Pants
These cozy duds have some of the best stats in the entire ultralight down pants niche, and they’re priced competitively.
- Price: $230
- Weight: 6.8 oz
- Fabric: 10D nylon ripstop
- Fill Power: 800 | Fill Weight: 2.8 oz
- Percent Down Weight: 42.3%
- Uncompressed Down Volume: 2400 in³
- Down Volume/Jacket Weight: 338 in³/oz
- Pros: Ultralight. High warmth-to-weight ratio. Generously filled. Great stats.
- Cons: Excess stitches create more cold spots.
Construction & Features
We will immediately call out that these pants have nearly three ounces of down fill, which makes them warmer than models like Ghost Whisperer and Flash. A 10d nylon shell keeps the entire package to just 6.8 ounces. Very impressive!
They have no features other than an elastic draw cord waistband. Perhaps their only downside is the grid pattern quilting, given that this is a sewn-through design. Each seam creates a micro cold spot, and these Montbells have way more seams than average. The look is kind of unusual compared to the horizontal baffles used on most other pairs.
Verdict
Choose these puffy pants for their warmer than average insulation value, lighter than average weight.
Kuiu Super Down LT Puffer Pants
Designed for hunting, but just as well suited to backpacking, the Kuiu Super Down LT Puffer Pants are lightweight and fully-featured, including full-length side zippers!
- Price: $269
- Weight: 8.3 oz
- Fabric: Toray® Nylon Ripstop – 29 g/m² (denier not listed)
- Fill Power: 850 | Fill Weight: 1.9 oz
- Percent Down Weight: 23%
- Uncompressed Down Volume: 1615 in³
- Down Volume/Jacket Weight: 195 in³/oz
- Pros: Ultralight. Hand pockets. Full length side zippers. Windproof. Good durability.
- Cons: Underfilled baffles are less warm than average, lower warmth-to-weight than peer group. Men’s fit only.
Construction & Features
For Kuiu Super Down LT Puffer Pants, the primary differentiating factor is their full-length side zippers. This allows for easy on/off without having to remove shoes/boots. It’s especially handy in winter, when you might also be wearing microspikes or snowshoes. Few other sub-10 ounce pairs offers this feature. We also really like the elasticized hand pockets, which are much more user friendly, albeit less secure, than zippered alternatives. This is a preferable design for access with gloves on.
The lightweight Toray ripstop nylon fabric is windproof, and noted as having a high durability-to-weight ratio; a natural fit for hunters who may be scrambling about on their knees. But it’s also great for backpackers who simply want their gear to last longer. The Quixdown down is DWR treated for superior performance in wet environments.
The biggest “down-side” to this garment is simply the fact that it’s baffles are underfilled. With just 1.9 ounces of 850 FP plumes, they’re the least warm down pants, in our guide. It would be a huge improvement to crank that fill volume up by about 50%.
Verdict
The Kuiu Super Down LT are the only pants in their weight class with full length zippers and pockets. If you value features and user-friendliness over pure warmth-to-weight ratio performance, these are a great choice. If you want the warmest ultralight option, look elsewhere.
Stellar Equipment Ultralight Down Pants 2.0
The Stellar Equipment UL 2.0 are notable for their capri cut, movement friendly stretch side panels, and full length zipper side panels.
- Price: $269
- Weight: 8.3 oz
- Fabric: Toray® Nylon Ripstop – 29 g/m² (denier not listed)
- Fill Power: 850 | Fill Weight: 1.9 oz
- Percent Down Weight: 23%
- Uncompressed Down Volume: 1615 in³
- Down Volume/Jacket Weight: 195 in³/oz
- Pros: Ultralight. Hand pockets. Full length side zippers. Windproof. Good durability.
- Cons: Underfilled baffles are less warm than average, lower warmth-to-weight than peer group. Men’s fit only.
Construction & Features
So why would you want down pants in capri form? A number of reasons! They’re easier to take on/off, they fit well with ski boots sans bunching, increase agility of foot placement, and focus the insulation where it’s needed most (your core, butt, thighs, etc). The downside being, it leaves calves uninsulated, thus making them a worse choice for pure winter camp wear.
Adding to the ski/movement focus are the stretch side panels and full length side zippers. These combine to allow for easier striding than with other pairs, and easier on/off; especially with ski boots.
While they warmth-to-weight numbers are mediocre due to all of the zipper and stretch fabric weight, they have about as much plumage in the baffles as all of the other ultralight down pants.
Verdict
Every design choice here is optimized for winter movement, rather than winter camping, which makes them our top pick for snow travel and ski touring. But you’re probably staying in a hut anyway, right?
Best Down Pants For Winter
Feathered Friends Helios Down Pants
When temps drop well below freezing, it’s time to whip out the Feathered Friends Helios Pants. Filled with 4.4 oz of 900 fill power plumage, these are some of the warmest puffy pants on the market, and perfect for use with skis or snowshoes thanks to the full-length side zip configuration.
- Price: $289
- Weight: 13 oz
- Fabric: 20D Pertex Endurance LT Nylon
- Fill Power: 900 | Fill Weight: 4.4 oz
- Percent Down Weight: 34%
- Uncompressed Down Volume: 3960 in³
- Down Volume/Garment Weight: 305 in3/oz
- Pros: Incredibly warm. Lightweight. High warmth-to-weight. Full length side zippers for venting and easy on/off. Sustainable fabrics.
- Cons: Bulky to pack. Midweight No pockets. Snaps can come undone.
Construction & Features
4.4 oz of down fill plump up the sewn-through baffles and keep your legs preposterously toasty. They’re too warm in temps at or above freezing, with a sweet spot in the 10-30F degree range. We love the use of sustainable shell fabrics; Pertex Quantum Pro is made with 60% castor-oil-derived nylon, and the interior liner is made with NetPlus post-consumer fishing nets.
They have dual full-length side zips, which allows the users to put the pants on without removing ski boots or crampons. However, ultralight hikers might find this to be a slight downside when not traveling in the snow. They add significant feature weight, bulk, structure, and manufacturing cost, while reducing the overall warmth-to-weight ratio of the garment.
The elastic waistband seals off with adjustable snap placements. However, we have experienced the snaps coming undone before. There are no pockets and no other features to write home about, so we conclude this section by addressing the 20d Pertex Endurance LT nylon. In our opinion, it’s the perfect tool for the job, a good blend of low weight and respectable durability.
Verdict
These are true winter down pants with massive total warmth, and a stellar warmth-to-weight ratio, and now best-in-class sustainable fabrics. They are mid-weight, very warm, well-made, durable, and have multi-sport versatility. The only downside is that they’re too warm for shoulder season, and you may not need or want the full length zippers.
Rab Argon Down Pants
When temps drop below 20, it’s time to whip out the Rab Argon. Stuffed with 5.6 oz of 800 fill power down, these are the warmest down pants in our arsenal, and the warmest pants we would conceivably need for anything less than arctic conditions.
- Price: $220
- Weight: 13.2 oz
- Fabric: 20D Pertex Microlight Nylon
- Fill Power: 800 | Fill Weight: 5.6
- Percent Down Weight: 42%
- Uncompressed Down Volume: 4480 in3
- Down Volume/Jacket Weight: 339 in3/oz
- Pros: Preposterously warm. High warmth-to-weight ratio. Good durability. Great value.
- Cons: Bulky to pack. Midweight. No Pockets. Not ultralight. No side zippers.
Features
We love that 42% of the garment’s total weight is down, which is top tier. And at $210 they’re actually a great value and killer deal.
Constructed with 20D Pertex microlight nylon, they’re light and reliably durable. They have a removable belt, which is nice as we’ve had issues with down pants sagging in the past. But beside that, there aren’t pockets and they’re basically featureless, which is fine by us as it saves weight and cost.
Our least favorite part is that there is no corresponding women’s cut, a huge oversight on Rab’s part.
Verdict
But for anyone who can wear the Rab Argon Down Pants, these are a killer value on an excellent winter weight pair of leg insulators.
Western Mountaineering Flight Pants
For snow camping, we recommend the Western Mountaineering Flight Down Pants with waterproof shell fabric on the seat, and front from hem to knee.
- Price: $375
- Weight: 12.5 oz
- Fabric: 20d nylon ripstop, WINDSTOPPER knees & seat
- Fill Power: 850 | Fill Weight: 4.0 oz
- Percent Down Weight: 32%
- Uncompressed Down Volume: 3400 in³
- Down Volume/Jacket Weight: 272 in³/oz
- Pros: Waterproof knees/seat makes snow camping easier. Warm. Full-zip sides.
- Cons: Expensive. Least warm in mid-weight category.
Construction & Features
There’s only so much to talk about when it comes to how a pair of down pants are designed, but this pair is interesting. While most of the body fabric is 20d nylon ripstop, large panels on the knees and seat are made with GORE WINDSTOPPER for very high levels of water resistance. This allows you to kneel and sit down on snow, perfect for managing camp chores.
The full side zippers are a necessary feature when it comes to use with skis, crampons, or snowshoes. While it adds weight, it makes them so much more useful for snow-travel.
Features aside, they’re only good-not-great when it comes to stats. The Flight Pants are more expensive, heavier, and have less down fill than other pairs of winter puffy pants.
Verdict
This is a great pair for ski touring, climbing, snow camping, and other situations where you find you will sit or kneel directly on snow. If you’re just backpacking on foot and it’s cold, look elsewhere.
Feathered Friends Volant Pants
For an expedition grade pair of down pants, designed for winter mountaineering, choose the Feathered Friends Volant. They’re the warmest and most protective pair in this guide, and overkill for all but the most extreme conditions.
- Price: $349
- Weight: 17.0 oz
- Fabric: 30d Pertex Shield XT Waterproof/breathable
- Fill Power: 900| Fill Weight: 5.6 oz
- Percent Down Weight: 33%
- Uncompressed Down Volume: 5040 in³
- Down Volume/Jacket Weight: 297 in³/oz
- Pros: Waterproof knees/seat makes snow camping easier. Durable. Warmest. Full-zip sides. Fully baffled.
- Cons: Bulky. Heavy. Expensive.
Construction & Features
These winter mountaineering pants are sure to invoke gear awe. First off, they’re made with a waterproof/breathable Pertex Shield Shell. This makes them great for camping, climbing, and living on the snow. You can sit, kneel, and lie down on snow, all without fear of soggy pants.
What’s more, Volant is stuffed with 5.6 oz of 900 fill power down. They’re the warmest pair in this guide, and we wouldn’t recommend them for temps above 10F, though they can go much lower. And did we mention they’re fully baffled? That means no sewn-through cold spots.
And like most skiing and mountaineering pants, they have full side zippers for easy on/off with skis, crampons, or snow shoes. This is critical on technical missions.
Okay, so you get all of those features, but there is downside. This is the heaviest pair on our list, by a wide margin. It is also the bulkiest when compressed – equivalent to a typical parka.
Verdict
If you need Feathered Friends Volant pants, you likely know who you are and whatever crazy mission you plan to use them on. Do not choose these pants for anything less than severe winter conditions.
Custom Ultralight Down Pants
GooseFeet Gear Custom Down
Adventure Alan himself prefers the GooseFeet Gear Custom Down Pants. From an ultralight connoisseur’s perspective, this is where you’ll find the highest warmth-to-weight ratio if you’re willing to place a custom order and wait for the five week lead time. Here are all of the customizable elements and some ideas for how to configure them.
- Shell/Lining Fabric color and 20d or 8d
- Ultralight backpackers should choose 8d
- Everyone else should choose 20d
- Baffles Vs Sewn Through
- Sewn through for use above 10F
- Baffled for use 10F & below (adds shell weight, decreases cold spots)
- Zippers: Every possible configuration
- No zippers for standard cold weather hiking and backpacking
- Full side zips for use with snow boots, crampons, ski boots, snowshoes, etc
- Down fill weight ranging from 2.5 oz – 8.5 oz. Temp ratings via GooseFeet Gear
- 3.5 oz of down fill for use in 30F and above
- 4.5 oz of down fill for use in 20F
- 5.5 oz of down fill for use in 10F
- 6.5 oz of down fill for use in 0F and below
- Waist, hips, inseam, thigh/calf girth
- Based on your body measurements
One potentially nifty customization is to get down capris. These should be cut to drape to your lower-mid-calf instead of the ankle, and have a girthy opening. This configuration allows you to take them on/off over your shoes without resorting to zippers or having to de-shoe. Very useful! Pair with high top booties for full coverage/no gaps above the ankle.
Choosing the Right Amount of Puffy Pants Warmth
In addition to choosing whether or not to pack puffy pants in the first place, you will want to choose a pair with the proper amount of insulation relative to the expected temperatures. You don’t want to underpack and be cold, but overpacking adds excess weight and bulk, and can even cause you to get sweaty.
Based on our personal experience cross referenced with GooseFeet Gear’s temperature recommendations, we recommend considering puffy pants whenever you expect evening temps below 40F. When you expect temps in the 30-40F range, choose a pair with 2-3 oz of down fill. When you expect temps in the 20-30F range, choose a pair with 3.0-4.5 oz of down fill. When you expect temps below 20F, choose a pair with at 4.5+ oz of down fill. Scale up the colder it gets.
Puffy Pants, in Conclusion
Thank you for reading our guide to ultralight down pants and backpacking and winter camping. Here you will find all of the best models available, and we know any one of them would serve you well. If you’ve never owned puffy pants before, you’re in for a life changing backcountry upgrade this season. Happy camping!
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