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Want a warm insulating layer without the cost and care required from down? In the last nine years, we've bought, tested, and reviewed over 50 of the best synthetic insulated jackets. For this recent iteration, we purchased 15 of the most highly regarded models and put them through our extensive side-by-side testing process. Synthetic insulated jackets have several advantages, including the ability to keep insulating when wet. They typically offer excellent breathability and generally cost less than down competitors. Whether you are looking for the warmest jacket to keep you comfortable in the coldest of temperatures, a lightweight and stretchy active layer to wear while working up a sweat, or a jacket with optimal wind resistance, we have you covered with some excellent and affordable recommendations.
Weight: 11.5 oz (M) | Number of pockets: 2 zippered hand, 2 internal
REASONS TO BUY
Killer warmth to weight ratio
Strong weather resistance
Stuffs easily into the included stuff sack
REASONS TO AVOID
Not very breathable
On days where cold winds move in during the afternoon, and you tighten your shoulders and core to try and generate some heat, you can pull on the Arc'teryx Nuclei FL for instant warmth. This lightweight jacket has just the right amount of Coreloft insulation to make it incredibly warm while keeping the weight down. We've seen similarly impressive offerings in the past from Arc'teryx (and Rab and Patagonia, for that matter), but none have hit the mark quite like the Nuclei FL. The fit is perfect; it features a long tail that covers most of your bum, sleeves that don't restrict movement through the arms and shoulders, and a hood that fits over a climbing helmet. Its included stuff sack is permanently fixed to an inside pocket, and this jacket stuffs and unpacks easier and faster than any model we've seen in over a decade of testing. The Arato face fabric has a very effective DWR treatment. Despite hearing that it's less durable than Pertex, we didn't feel like the Nuclei is any more fragile than its closest competitors; plus, it has a softer feel and no crinkle factor.
This jacket is not a breathable model for stop-and-go activities. Even on easy hikes and approaches, we found ourselves shedding this layer after only a few minutes. Sweat will build up, and the moisture has nowhere to go, so if you aren't careful, you can become a sweaty (and potentially cold) mess. For the Nuclei to be a good mid layer, it needs to be really cold out. It's better suited as a terminal layer on moderately cold days or when you're staying put in camp or hanging out at a belay. Our review selection has similarly performing jackets, but none hit the spot like the Nuclei FL.
Weight: 16.75 oz (M) | Number of pockets: 2 zippered hand, 1 zippered internal chest
REASONS TO BUY
Optimal fit for use as an outer layer
Lighter than other super warm options
REASONS TO AVOID
Doesn't stuff into own pocket
Not very breathable
A bit pricey
Arc'teryx recently updated most of its synthetic jacket lineup by changing the fit and swapping out the fabrics used for better options. We love the subtle but significant updates, as these jackets are now easily among the most comfortable. The heaviest and thickest model we've reviewed is the Arc'teryx Atom AR Hoody, which is our favorite option when we need warmth above all else. It mixes and matches different densities of Coreloft insulation depending on body location, with the majority being a whopping 120 g/m2. This super warm jacket maintains an impressive weight and has an excellent fit for use as an outer layer. There remains plenty of room on the inside for base and mid layers, without feeling overly stuffed; the arms, shoulders, and hem are all generously sized to give ideal flexibility when skiing, climbing, or even chopping wood. Simply put, this jacket is easily one of the warmest we've tested and it's far more comfortable and ideal fitting than its closest competition.
As you may expect from a jacket designed to trap as much heat as possible — this one isn't very breathable. The moment we started moving, we usually needed to take it off (although on a few hikes in ~10F weather, we simply kept it on). It's also a bit heavy and bulky, which is another downside of added warmth. There are also more affordable choices to be found if budget is your primary consideration. If you need a warm jacket for everyday use in the winter or an outer jacket to keep you warm when you take breaks on the skin track or while belaying in the ice park, this is the first one we recommend checking out.
Weight: 13.2 oz (M) | Number of pockets: 2 zippered hand, 1 zippered internal chest
REASONS TO BUY
Thin and very breathable
Excellent fit for active use
REASONS TO AVOID
Doesn't pack into its own pocket
Active insulated layers have come to dominate this genre of jackets, with the Arc'teryx Atom LT representing the cream of the crop. These jackets tend to be much lighter, with less insulation and excellent breathability, and are typically made of stretchy fabrics to allow for the largest range of motion. We love the Atom LT; its fit suits climbing, running, skiing, or performing any other cool outdoor sport — a low hem, long arms, and not overly baggy, with excellent shoulder mobility so that we never feel constrained. We found the fit far more athletically minded than the overly constrictive Patagonia Nano-Air, a jacket that has come to define this category. It also pairs lightweight and breathable stretch fleece panels along the side of the body with lightweight Coreloft insulation everywhere else to make it better than any other we've tested at regulating our temperature while working hard.
Active layers are designed to be worn when active, protecting from cold air or wind, but breathable enough that they don't get so hot that you need to take them off. Naturally, they are pretty thin; if you expect to wear this jacket as a standalone in winter without moving your body to stay warm, you will likely end up feeling pretty cold. It is also an excellent mid layer for added warmth beneath a thicker outer jacket or shell. We loved it as a winter running jacket, wearing while skinning uphill, winter bouldering, and even for high output nordic skiing. It also serves as a lightweight jacket for chilly mountain evenings and mornings during the summer or shoulder seasons, when a heavier jacket would be overkill.
Weight: 11.8 oz (M) | Number of pockets: 2 zippered hand, 1 zippered external chest
REASONS TO BUY
REASONS TO AVOID
Poor water resistance
The Rab Xenair is a minimalist-style insulation layer that works well as a standalone piece when you anticipate high output in a cold climate or to increase the warmth of a layering system without adding a lot of bulk. It's a highly packable and layerable piece of insulation. Different portions of the jacket use different weights of insulation; for example, more is used around your core and less insulation around your extremities to prevent you from overheating. The Primaloft Gold Active+ insulation, combined with the Pertex Quantum Air shell fabric, makes this jacket incredibly breathable without sacrificing its ability to protect you from the wind. The lack of a hood and other features allows this jacket to pack down small and be stowed away in a pack or clipped to the back of a harness.
This layer runs large; our testers found that they could have easily sized down from their normal sizing. The roomy fit in the shoulders through the arms does make moving around in this jacket comfortable. The other major drawback is the lack of waterproofing. While the synthetic insulation keeps insulating you when wet, the outer shell won't prevent this jacket or whatever you wear underneath from soaking through. On the bright side, its streamlined design makes it easy to layer over. We'd recommend this jacket to anyone looking for a lightweight insulation layer that breathes incredibly well.
Weight: 12.4 oz (M) | Number of pockets: 2 zippered hand, 1 zippered internal chest
REASONS TO BUY
Lightweight and compact
Excellent wind resistance
Solid at repelling water
REASONS TO AVOID
Fit is large
Doesn't breathe well
Not an ideal mid layer
The Rab Xenon 2.0 has long been one of the top performers in our comparative testing and one of our favorite synthetic insulated jackets. It shares some of the same characteristics as the Patagonia DAS Light Hoody and the Arcteryx Nuclei FL but is significantly more affordable, making it an optimal choice for the budget-conscious. It also features a very smooth and slick seamless face fabric that does a great job resisting the wind, which contributes positively to its overall warmth effect. It's lightweight, highly packable, and has a very effective DWR treatment in case you get stuck in a spot of rain or snow. Overall, this is an excellent outer layer that is also one of the most affordable options you will find.
As with any product, there are a few downsides. With a highly wind-resistant shell, the trade-off is much poorer breathability than its stretchy counterparts. We also found the fit quite large and borderline baggy, so consider sizing down if you fall between sizes. It's easy to fit layers underneath this jacket, but the larger fit prevented us from wanting to use it as a mid layer very often. It's also not quite warm enough for us to consider using as a daily winter jacket, and we think it's best suited specifically for outdoor missions. As a wind-resistant, insulating outer layer, this jacket cannot be beaten for almost any cold-weather activity such as hiking, biking, climbing, or running.
This review is a collaboration between three of our top reviewers: Andy Wellman, Matt Bento, and Buck Yedor. Andy is a former climbing guidebook publisher who has spent many years reviewing down jackets for OutdoorGearLab, before switching over to cover insulated jackets. As a lifelong and obsessive climber, backcountry skier, backpacker, and mountain town liver, Andy has spent pretty much his whole life wearing insulated jackets, of both types, for comfort and out of absolute necessity.
Between his time on Yosemite Search and Rescue, and the last ten years spent climbing and living out of his vehicle, Matt has spent his fair share of time in cold weather. This way of life means that Matt is outside in the elements regularly, perpetually putting his gear to the test. With such a constant and varied need for quality gear, Matt has a unique foundation of knowledge to test and judge insulated jackets.
Buck was born in the Colorado Rockies and has spent much of his life in California's Eastern Sierra. Another alumnus of Yosemite Search and Rescue, Buck knows that having a high-quality insulating layer can make a world of difference in terms of your health and happiness when going out into the cold.
Choosing which jackets to include in this review starts with lots of research by our reviewers and editors, ensuring we keep our finger on the pulse regarding the newest technologies and upgrades in the market. After buying every model you see here, a tactic that allows us to maintain our unbiased stance, we put these jackets to the test in the real world, using them the same way you do, or would like to. We wear them while backcountry skiing, backpacking, hiking, ice, and alpine climbing, belaying when the temps are "sendy," shoveling our walk, walking our dog, nordic skiing, sitting around the campfire, and almost all moments in between. We also devised more objective tests, eventually rating each product on several metrics, including warmth, weather resistance, weight and compressibility, breathability, and style. The recommendations you find here are the product of this hands-on testing.
The jackets tested in this category all use a variety of synthetic insulation. In recent years, there has been a significant shift in the insulated jacket market; there are now two main kinds of jackets: Active insulating layers and insulated jackets for warmth. Active layers tend to be thinner, made with stretch fabrics, and are highly breathable. They are designed to be worn all the time, can be layered over, and thrive on winter days when you are working up a sweat.
Traditionally, insulated jackets have been designed to be warm and present a less expensive and more water-resistant option compared to down. These jackets still exist, and we have tested both varieties in this review. While we grade each choice on the six metrics described below, be sure to identify which type of jacket — active or warmth — is likely to serve you well and aid in determining the best fit for your needs.
A good insulated jacket doesn't have to cost an arm and a leg, but you should plan on spending a good chunk of change for excellent quality. Synthetic jackets have historically been less spendy than down competitors, but with their rise in popularity, the field (at least price-wise) has evened out.
The Rab Xenair Insulated is a perfect example of excellent value. It's one of the least expensive options in the field and is still an excellent performer.
The Rab Xenon 2.0 is a runner up for having a notable price point, as is the Rab Nebula Pro. We also want to highlight top performers like the Arc'teryx Nuclei FL, Patagonia Nano Air Hoody, and Arc'teryx Atom LT. While these models cost more than the Rab Xenair, they are some of the top performers in our fleet; as such, they represent an excellent value for your money.
First and foremost, your jacket, combined with your other layers, needs to keep you warm in the weather you plan to use it in. We've weighted this metric most heavily — 25% of each model's score. Gram for gram, down insulation is warmer than synthetic insulation; however, advances in synthetics materials are quickly catching up to the superior warmth-to-weight ratio of down. However, the scores awarded to the jackets in this review only compare their warmth relative to each other, not compared to down jackets. Since this review includes thick and thin jackets, ones designed as activewear, and those designed for maximum warmth, it's probably helpful to identify what type of jacket best suits your needs before giving too much importance to absolute warmth. After you know which kind you want, compare like types to like types.
The warmest choice in our fleet is the Arc'teryx Atom AR, which has the side benefit of looking nice for around-town use, and features 120g/m of Coreloft insulation in the torso region. The Rab Nebula Pro also gets top marks for warmth and will be a little easier on your wallet, though you'll need a shell during the worst weather. Comparing warmth between lightly insulated models is challenging. Some are designed to allow wind to blow through portions of the jacket for breathability, while others are wind resistant. To pick a comparison point, we rated their warmth as an outer layer when worn over base layers with a light breeze.
Among the lighter weight models tested, the Arc'teryx Nuclei FL, Patagonia DAS Light Hoody, and the Black Diamond First Light Stretch Hoody are rated the warmest choices. Some very light jackets can still be impressively warm. For instance, the Patagonia Micro Puff uses PlumaFill insulation, resulting in extraordinary warmth, despite being the lightest jacket in the review by several ounces. Unfortunately, its super lightweight shell makes it vulnerable to abrasion from rocks and brush. Additionally, the PlumaFill tends to leak out in long strands once there is a tear in the shell. The Rab Xenair is another incredibly light option that still provides a good amount of warmth. It is, however, one of the least waterproof options we tested.
Weight & Compressibility
Since we find ourselves taking an insulated jacket pretty much everywhere, light is usually right. All else being equal, we'll choose the lighter, more compressible model almost every time for outdoor pursuits. The Patagonia Micro Puff takes the lightweight cake, weighing in at a mere 9.30 ounces for a size medium. The Outdoor Research Helium Insulated Hoodie is the next in line, at 10.80 ounces for a size medium. The Arc'teryx Nuclei, Patagonia DAS Light Hoody, Patagonia Nano Air, and the Rab Xenair are also all commendable choices. All have outstanding warmth-to-weight ratios when used as a mid layer. If you are looking for the perfect balance between warmth and weight, it's hard to beat the Xenon. It's less expensive than many competitors and significantly more durable than the Micro Puff.
We appreciate a jacket that stows away in one of its pockets. This makes just-in-case storage in a backpack easy and keeps the outer fabric clean, protecting its DWR treatment. Most models tested stuff into a pocket or come with a stuff sack. The Xenon is one of our favorite stuffable pieces, as it is compact, has a clip loop, and regularly traveled on our testers' climbing harnesses. The minimalist Rab Xenair is another nice option that stuffs into its own pocket and packs down small enough to clip to a harness.
While it is a top scorer, the Arc'teryx Atom LT Hoody doesn't include a stuff sack or a stuffable pocket option. The Patagonia Nano-Air Hoody stuffs down into its pocket, except that it's so challenging to get the jacket to fit in the pocket that we didn't find this feature very useful. The Arc'teryx Nuclei FL has a stuff sack permanently attached to the inner pocket. While it doesn't technically stuff into its own pocket, we found this design equally effective and easier to use than many stuff pocket designs. We assigned weight and compressibility 20% of a product's final score.
While synthetic insulation has become more compressible, long-term durability is still an issue. The fiber's ability to rebound to full loft decreases with repeated compression, and the more tightly compacted they are, the more wear the fiber matrices incur; we recommend that you always store jackets in their uncompressed state.
In this category, we assessed each piece's mobility, as well as small details that made each more comfortable. We found that some moved with us better than others; some had features, like fleece-lined chin guards or hand pockets, that deliver happiness for minimal weight. We also note the fit characteristics of each jacket; this gives you a better idea of which body types each jacket fits best and can help you choose the correct size.
Let's discuss mobility first, as this is a crucial jacket attribute. When you reach overhead while climbing or digging in your pack, a model that stays put (without the waist hem being tugged upwards) is appreciated. We also assessed how well we could move our arms, as well as the hood mobility. Ease of use is another consideration when comparing jackets. Nice zipper pulls, pockets in the right places, and convenient hood adjustments are a few features that contribute to higher comfort scores. The texture of interior fabrics and the presence, or not, of features such as soft chin guards are nice touches that also affect a jacket's comfort level.
We've found that Arc'teryx jackets, in particular, stand out when it comes to comfort due to a combination of unobstructed mobility, perfect fit, and soft, comfy fabrics. The Arc'teryx Proton LT Hoody, Nuclei FL, Atom LT, and Atom AR all received high comfort scores; with low-bulk cuffs, well-shaped zipper pulls, very comfortable inner fabrics, and excellent mobility. Among the heavier, warmer options, we think the Rab Nebula Pro is remarkably comfy, with thoughtful features like a padded collar and fleecy pockets. Comfort accounts for 20% of a product's final score.
We've all found ourselves in torrential downpours and fierce winds despite a bluebird forecast. In these situations, the right insulated jacket can significantly reduce the suffer factor. Most of the products tested are designed to be worn primarily as a mid layer with a rain jacket or hardshell on top for foul weather. That said, many users employ these products as their outer layer if the conditions aren't too severe. We've worn all of these jackets as outer layers in all sorts of weather while climbing, skiing, and simply hiking and have found some that provide significantly better protection than others.
Insulated jackets are usually not designed to be waterproof or windproof. If you're looking for a jacket that combines the warmth of an insulated jacket with the weather protection of a hardshell, consider a ski jacket.
Models with a continuous or nearly continuous outer fabric do a better job of stopping the wind. The Arc'teryx Nuclei FL and the Patagonia DAS Light Hoody are the most weather resistant of the insulated products tested. All three feature slippery nylon ripstop fabric with a durable water repellent coating that works in light rain and snow, making them practically windproof, and have a design that minimizes seams where air can leak. These are the only light models we'd purposefully wear without a shell during a short, light rain. However, the Arc'teryx Atom AR Hoody also beads water and offers a high level of water resistance. The Rab Xenair has average water resistance, but the Pertex Quantum Air shell does a great job at keeping out the wind.
Hoods or No Hood?
We enjoy having hoods since they provide a warmth upgrade for little weight. A hood is impossible to misplace, unlike a hat. We wore hoods under and over climbing helmets. Our favorite hood designs feature cinch cords that tighten the hood around the head and not the face, although more and more hoods are being designed with only elastic to secure the facial opening. While this design is lighter and simpler, it cannot adjust depending on your head shape or the weather. A hood can sometimes get in the way if you're planning to wear your layer primarily under a shell that has its own hood. Most hooded models tested are available in hoodless versions, which we noted in our specs table.
All of the models tested are meant to have a Durable Water Repellent (DWR) treatment applied to the face fabric. This causes light rain to bead off the shell and keeps insulation dry, as long as it is effective (not all are). The treatment on the Proton LT was the most effective of those found on stretchy, breathable face fabrics. The DWR treatments on some of the other lightweight jackets are far less effective. Weather resistance accounts for 15% of a product's final score.
Breathable insulated jackets are a newish arrival on the outerwear scene and are designed to regulate temperature and wick sweat during high-energy activities in cold weather. The introduction of Polartec Alpha and, more recently, FullRange insulation from Patagonia allows a new approach to breathability. The insulation itself moves moisture and promotes better airflow. Perhaps the most popular and recognizable of these jackets, the Patagonia Nano-Air Hoody, pairs FullRange insulation with stretchy, breathable shell fabric and a moisture-wicking lining to create one of the most breathable models tested.
The Nano-Air Hoody is one of the most breathable options, according to our testing. Not far behind is the Arc'teryx Proton LT Hoody. The Proton isn't as light as the Nano-Air, but it's nearly as breathable and much more durable. Other companies have also begun imitating this style of jacket. These jackets are game-changers for high-energy activities like backcountry skiing, cross-country skiing, and winter running. Pair these with a lightweight windbreaker if you need some outer protection.
The long-standing approach to making a Primaloft or Coreloft product better suited to exertion is to incorporate low-bulk, breathable panels under the jacket's arms and on the sides. The Arc'teryx Atom LT takes this hybrid approach. Wind-resistant fabric protects your core, while stretchy side panels dump excess heat. This hybrid earned top breathability scores. The medium and heavy models tested were the least breathable, but they work the best as terminal layers, keeping you warm when you've stopped to take a break while hiking or waiting at a windy belay station. While breathability is a critical component of a synthetic jacket's performance, especially the active layers, it's also very hard to quantify. For that reason, we weighted it as 15% of a product's final score.
With the vast assortment of choices available, choosing the best jacket can be tough. We rank warmth and weight high on the list of essential attributes, yet other features, such as weather resistance and breathability, may prove significant depending on your use. Remember to ask yourself what you'll be doing in your insulated jacket. Will you be running or ski touring? Maybe you're backpacking and not expecting to use an insulating layer all that often? You may want to go for something light and breathable and choose an active mid layer. Want a single jacket that will work nearly every day or activity you may need it for? Then look no further than the Arc'teryx Nuclei FL, DAS Light Hoody, or the Rab Xenon 2.0.
A solid base layer is at the core of keeping you warm...
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