There’s nothing that will ruin a day on the mountain more than being cold – well, maybe besides long chair lift lines. Your body needs to be at the proper temperature to stay on the slopes and out of the lodge. The best way to do this is by investing in a reliable pair of thermals or long underwear. This underwear should be cozy, warm, functional, and even able to handle a few wipeouts. But, how do you choose the best long underwear for skiing?

Well, let’s hit the slopes, and find out!

Strap on your boots so we can explore the ten best long underwear for skiing for both men and women!

Disclaimer: To maintain genuineness and authenticity, Merino Wool Gear DOES NOT sponsor products. Yet as an Amazon Associate, we may earn a commission from qualifying purchases.

Long Underwear Buying Considerations


If you’re hitting the slopes, you’re going to need to stay warm (no, duh, right?). Maintaining a proper temperature is not merely about material thickness, although there is a strong correlation between them. It also has to do with the breathability and moisture-wicking ability of the material since you will most likely be sweating as you’re riding tips up through the fresh powder. If you are sweating too much, your skin will cool down, and you’ll be freezing. Remember that the thicker the fabric weight, the warmer it will be, and the less breathable.


Apart from being warm, you should look for long underwear that’s tight but not restrictive. It should be supportive of all the right parts. If it’s too snug, you’re going to be super uncomfortable as you try to maneuver around the mountain. Still, if it’s too loose, you may get bunching and clinging in all the wrong places.

On top of the tightness, you should want your bottoms to feel smooth on your skin. Not only does this have to do with the fabric makeup, but also the stitching and waistband construction. Look for clothing with flatlock seams and a durable waistband to avoid any unnecessary irritation.


Long underwear does not always mean it has to go down to your ankles. In fact, when you wear an ankle-length base layer in addition to a heavy sock may make it more uncomfortable when you try to strap on your boots. Also, boot bunching may be more than just irritation, as it can be a prime chafing area and may reduce the blood flow to your feet. We aren’t saying that full-length underwear is not great (actually, we prefer it), but the overall length is definitely something to consider.


Combining insulation, comfort, and length, we have the most critical factor in long underwear for skiing: function. You should look for bottoms that provide you with the best practicality for your style. We mean that the leading factor in purchasing skiing underwear is that they keep you on the mountain. We’ve come up with a simple rule: the best underwear are ones that you never feel.

Merino Vs. Synthetic Long Underwear For Skiing

We’d like to note that we are a website dedicated to Merino Wool Gear (hence the name), but we want to be objective with our reviews. It’s essential to look at the positives and negatives of Merino Wool as compared to other synthetic long underwear.

Merino wool is one of the best fabrics for keeping your microclimate – the area between your clothing and skin – warm. It wicks away moisture from your skin and holds your traps air and water vapor within the material. Merino also has odor-resistant properties, is incredibly soft on your skin, and can be versatile in any environment. Some of the downsides are that it can be pricey and can have durability issues if not cared for properly.

Synthetic materials like nylon and polyester are incredibly breathable and quick-drying, which is excellent if you wipe out and get snow up your pant leg. They tend to be more durable and less expensive than Merino wool, as well. While synthetics don’t always provide the best insulation, it’s often enough to keep you warm. As the material is made from petroleum, it’s hydrophobic, meaning that it repels water and attracts oils. Thus, the smelly, oily secretions from your body tend to linger in the fabric. On top of that, it’s very environmentally friendly.

What’s Best For Skiing?

The decision of which long underwear material you should wear on the slopes is ultimately up to you. If you favor durability and a little bit of extra cash in your wallet, you may want to be on team synthetic. But we honestly prefer Merino, as we believe temperature regulation and comfort are the most crucial underwear factors while skiing.

We will focus mainly on the top Merino long underwear for a day on the slopes due to our preferences. Still, we’ll also go over some reliable non-Merino options for those of you who prefer synthetics. Let’s get started!

Best Long Underwear For Skiing: Tie

Icebreaker Merino 200 Oasis Leggings

100% Merino wool | 200 gsm | Slim fit | Price: $$$

Icebreaker Oasis 200 Leggings Mens and Womens in Gray

Men’s Oasis Leggings | Women’s Oasis Leggings

Pros: Fantastic warmth-to-weight ratio | High performance | Sleek and stylish

Cons: User-reported fabric issues | The waistband is a bit snug

View Icebreaker Sizing Charts & Brand Review

Style meets functionality with Icebreaker’s Merino 200 Oasis Thermal Leggings for men and women. The 100% Merino wool jersey fabric is extra soft on your skin and offers ample breathability to regulate your temperature.

We love the choice of midweight, 200 GSM fabric density as it is sufficient enough to keep you warm in an ever-fluctuating alpine environment. Also, we feel that these Oasis leggings are one of the most multifunctional options on our list, as you can wear them as a standalone piece.

Although no pair of long underwear is perfect, we’ve seen a couple of reported issues. Some users have claimed that the waistband feels too tight, and others say that the fabric wears over time. It appears as the former may be due to personal preference, and the latter to improper care, as we have not experienced these issues personally.

Overall, we feel that any clothing crafted by Icebreaker is worth its weight in gold. Okay, maybe that’s a bit of a stretch, but Icebreaker should still be crowned co-king of the mountain with their Oasis 200 Thermal Leggings.

Smartwool 250 Base Layer Bottoms

100% Merino | 250 gsm | Slim fit | Price: $$$$

Smartwool Classic Thermal Bottoms Men and Women

Smartwool Men’s Thermal Bottoms | Smartwool Women’s Thermal Bottoms

Pros: Excellent thermoregulation | Design improves comfort | Trusted outdoor brand

Cons: May stretch with improper care | Relatively slow-drying

View Smartwool Sizing Charts & Company Profile

Our co-best pair of Merino wool long underwear is none other than the Smartwool Merino 250 Bottoms. They are a bit thicker than their co-champion, making them slightly better in the warmth category. Still, despite being 250 GSM, these Merino bottoms are surprisingly breathable, offering plenty of temperature regulation as you navigate the mountain all day long.

The actual reason that we love these long underwear is Smartwool’s attention to detail within the design. It’s the little things like a thick Merino-lined waistband for maximum comfort and garment-wide flatlock seams to reduce irritation. Smartwool even redesigned their back gusset pattern due to user feedback, allowing for a much more supportive fit.

The fit is not too tight either, so that you can wear these bottoms as a mid-layer. But be careful as the fabric may deform over time with improper care.

Overall, it’s a no-brainer to put a trusted Merino brand like Smartwool as the co-gold medalist when it comes to the best long underwear for skiing.

Note: If you’re looking for a similar construction and reputation as the Smartwool 250 Bottoms, but don’t need as thick of fabric, check out their 150 bottoms. It’s the same design but doesn’t offer as much warmth protection.

Best ¾ Length Merino Long Underwear For Skiing

Ridge Merino Men’s Aspect 3/4 Bottoms

84% Merino, 16% Nylon | 180 gsm | 18.5 microns | Slim-to-Athletic fit | Price: $$

Ridge Merino 3/4 Aspect Bottoms

Pros: Excellent breathability | Comparatively more durable | Relatively inexpensive

Cons: Not as warm as other options | May be tight around larger calves

View Ridge Merino Sizing Charts & Company Profile

Suppose you’re sick of the sock-underwear-boot irritation combo but still want the protection provided with long underwear. In that case, the Ridge Merino 3/4-Length bottoms may be your best bet. They offer a supportive but not too restrictive fit. Their 180 GSM fabric provides sufficient warmth for sunny days on the mountain.

One aspect we love about the Aspect – and a lot of Ridge Merino clothing in general – is the dedication to the clothing’s longevity. By itself, Merino wool is sometimes too delicate to withstand the normal wear and tear of long skiing underwear. Ridge Merino utilizes an industry-leading (m)Force Merino technology, spinning the soft woolen fibers around a stronger nylon thread to improve durability and longevity. You get all the benefits of Merino and minimize some of the disadvantages in the process.

The calf holds are great for these specific thermals, but they may be a bit tight for those with tree trunks for legs. Also, for shorter people, the 3/4 length is more like 7/8, so keep that in mind.

Still, you truly can’t beat the price-to-quality ratio that Ridge Merino provides with this skiing underwear. They may be 3/4 length, but they are 1/2 the price of most of the competitors. We highly suggest the Ridge Merino Aspect leggings if you want to feel comfortable on the mountain without breaking the bank.

Minus33 Women’s Osceola 3/4 Bottoms

100% Merino wool | 235 gsm | 18.5 microns | Standard fit | Price: $$$

Minus33 Womens Osceola Three Quarter Merino Wool Bottoms Black

Pros: Soft & comfortable fit | Ideal length for ski boots | Good temperature regulation

Cons: User-reported sizing issues | Stretches with excessive use

View Minus33 Sizing Charts & Company Profile

Minus33 has crafted a simplistic yet aesthetically-pleasing pair of ladies leggings with these Osceola Midweight Wool 3/4 Bottoms. The 235 GSM fabric will keep your legs warm on the mountain but still allow for plenty of room to breathe.

The Osceola leggings’ minimalistic design may appear basic at first, but Minus33 has put so much detail into every inch of them. The waistband is covered and rises higher, sitting around the belly button. The gusset construction and flatlock seams reduce irritation and chafing. On top of that, the 3/4 inseam reduces any annoyance from “boot bulk.”

It’s important to note that these Merino bottoms are not as tight-fitting as many of the other pairs on our list. They have a much more relaxed fit, which is why some users have reported that they run a bit large. Minus33 suggests that you size down if you are looking for a more athletic fit.

Overall, we think the Osceola Minus33 3/4 bottoms aren’t just a fantastic pair of long underwear on the slopes. They also work well in the yoga studio, CrossFit gym, or even just lounging around the house.

Most Affordable Merino Long Underwear For Skiing

Meriwool Merino 250 Base Layer Bottoms

100% Merino wool | 250 gsm | 18.5 microns | Regular-to-Loose fit | Price: $$

Men’s Base Layer 250 | Women’s Base Layer 250

Pros: Excellent price-to-quality ratio | Soft to the touch | Versatile

Cons: Stretches with heavy use | User-reported excessive pilling

View Meriwool Sizing Charts & Company Profile

The price of lift tickets is high, so if you want to hang out all day on the mountain, you will have to cut back the cost somewhere else. With the Meriwool Merino 250 Base Layer Bottoms, you’re able to save a little bit of money without sacrificing warmth. It’s the perfect combination for a fun, wallet-friendly day on the slopes.

The 18.5-micron, 100% Merino wool feels super soft on the skin, while the 250 GSM fabric provides excellent temperature regulation. At the end of a long day, they won’t even stink either. You can use them again when you conquer the fresh powder the next day!

The fit is a little baggier than we expected, and for us, it seemed to be a bit tighter around our thighs than it was our waist. We didn’t see this as an issue, but it’s just a feeling we weren’t used to. According to some users, the fabric itself stretches with heavy use, but that’s typical with pure Merino clothing.

In the end, the Meriwool 250 Base Layer Bottoms are super-efficient in what they are meant to do: keeping your legs – and bank account – protected. Check out the variety of color options for both men & women below.

Best Long Underwear For Backcountry Skiing

Minus33 Katmai & Kenai Expedition Wool Bottoms

100% Merino wool | 400 gsm | 18.5 microns | Regular fit | Price: $$$$

Minus33 Expedition Weight Merino Wool Bottoms Men and Women Black

Men’s Katmai Expedition Bottoms | Women’s Kenai Expedition Bottoms

Pros: Warmest pair on this list | Soft next-to-skin comfort | Surprisingly breathable

Cons: User-reported fit issues | Expensive

View Minus33 Sizing Charts & Company Profile

Skiing in the backcountry can be exhilarating. It’s like you are a polar explorer, testing your limits against both the beauty and brutality of nature to find that perfect line. Venturing into these uncharted territories often means unknown weather conditions. That’s where the Katmai and Kenai Expedition bottoms by Minus33 come in handy.

These Merino wool bottoms have a fabric thickness of 400 GSM, nearly twice as much as any of the other pairs on our list. For reference, that’s about six pieces of paper thick. You know they will provide excellent insulation, but the surprising thing is that they are also breathable despite their thickness. The soft, 18.5-micron fibers also feel super soft on your skin. The combination of protection and comfort sometimes makes it feel like you aren’t wearing any long underwear at all!

The fit itself is a bit relaxed, which has led some users to report sizing issues, but it’s not anything we have seen. Also, they are the most expensive pair of thermals on our list. But, with features like flatlock seams, structured gussets, a covered waistband, and 400 GSM of insulation, we feel like they are priced appropriately.

So, if you want to take an expedition into the unknown, make sure to stay comfortable and protected with these Minus33 Expedition long underwear.

Best Non-Merino Long Underwear For Skiing

Arc’teryx Rho LT Bottoms

Torrent: 84% Polyester, 16% Elastane | 175 gsm | Next-To-Skin fit | Price: $$$

Men’s Rho LT Bottoms | Women’s Rho LT Bottoms

Pros: Comfortable & snug | Unexpectedly warm | Excellent durability

Cons: Somewhat “staticy” | Limited versatility

In these reviews, we typically only focus on Merino wool gear (hence the site name). But, we feel like we would be doing you a disservice by writing an article about the best long underwear for skiing and not include the Rho LT from Arc’teryx. These super lightweight leggings are shockingly warm, and they hug your legs in all the right places.

With a well-established outdoor brand like Arc’teryx, you know you’ll be buying a finely engineered product, and the Rho LTs are no exception. The Torrent fleece fabric (84% polyester and 16% elastane – is brushed during manufacturing to give a soft next-to-skin feel and speed up moisture transfer away from your body. The elastic stretch and articulated pattern offer a fit that works with you as you move rather than against you. Heck, there is even a well-designed crotch gusset and zipper pocket!

As we try to remain objective with our reviews, it’s important to detail some of the cons. There have been reports that due to the Rho LT’s tight fit and brushed fleece, they offer limited breathability. These bottoms are also on the Merino spectrum’s pricier side, but we think the price point is fair with the sheer amount of extra features.

Overall though, the Arc’teryx Rho LT Bottoms are one of the most form-fitting, high-performing pair of thermals that we’ve tried. That’s why they make our list as the top pair of non-merino long underwear for skiing for both men and women.

Best Long Underwear For Skiing: Honorable Mentions

Ortovox 185 Rock’N’Wool Short Pant

100% Tasmanian Merino | 185 gsm |19 microns | Athletic fit | Price: $$$$

Ortovox Mens and Womens Rock N Wool Short Pant

Men’s Rock’N’Wool Pants | Women’s Rock’N’ Wool Pants

Pros: Great breathability | Excellent fit | Quick-drying

Cons: Not the warmest | Relatively Expensive

These Rock’N’Wool short pants also have excellent design features that hinge on functionality. The athletic fit is not too loose or too tight, offering the right amount of support in all the right places. They hug your thighs and calves just ever so slightly but have a relaxed area around the knees for improved mobility.

The Ortovox Rock’N’Wool Short Pant also offers a stellar warmth-to-weight ratio. Still, they aren’t the warmest pair of long underwear that we’ve seen. In our opinion, they are best suited for spring skiing when temperature fluctuations aren’t as high. However, they do offer excellent breathability and relatively quick-drying than some of the other pairs of Merino long underwear on our list.

Outdoor Research Alpine Onset Bottoms

47% Merino /47% Polyester / 6% Elastane | 150 gsm | Tight fit | Price: $$

Outdoor Research Onset Alpine Merino Bottoms

Men’s Alpine Onset Bottoms | Women’s Alpine Onset Bottoms

Pros: Super lightweight | Breathable | Quick-drying

Cons: Not for extreme temps | Reported seam issues

Suppose you are typically toasty in your snow pants and only need a small extra layer of protection. In that case, the Outdoor Research Alpine Onset Merino Bottomss may be your best choice. They are super lightweight and have excellent breathability properties. The fabric is a blend of recycled polyester and Merino wool, making them a perfect eco-friendly skier option.

The main issue (if you can call it that) we have with the Enigma bottoms is that they only have a fabric thickness of 150 GSM. In other words, they are not ideal for ultracold summit conditions. On top of that, some users have reported minor seam irritation and potential fabric snagging issues. Still, if you are looking for an ultralight pair of long underwear that still holds its weight, then check out the Outdoor Research Apline Onset Bottoms.

Patagonia Capilene Midweight Bottoms

100 % Capilene (recycled polyester) | 147 gsm | Relaxed fit | Price: $$

Patagonia Capilene Midweight Bottoms Mens Womens

Men’s Capilene Bottoms | Women’s Capilene Bottoms

Pros: Weighs next to nothing | Relatively Inexpensive | Great Breathability

Cons: Fit a bit too relaxed | Reported durability issues

It’s tough to make a list of skiing gear and not include Patagonia. Their midweight Capilene bottoms are an excellent, budget-friendly choice for skiers of any skill level. Even though they are incredibly lightweight, they still offer adequate insulation against moderate alpine conditions through diamond-like shapes in the fabric that trap in hot air.

One issue we’ve seen with the Capilene midweight bottoms is that they feel too relaxed and saggy. We don’t 100% get the proper support that we would like from a pair of long underwear. It’s not like they perform poorly in the comfort department; it’s more of a personal preference.

Final Note: Best Long Underwear For Skiing

It’s the last call for the chairlift, and the sun is setting over the mountains on the best long underwear for skiing. We hope you’ve gained some knowledge about the multitude of factors that go into making a great pair of thermals as you carve down fresh powder. Always keep your legs warm and your tips up!

Remember to gather more information from as many sources as you can before purchasing any of these bottoms, as it’s you – not us – that will be wearing them on the slopes. All we try to do is impart a shred of insight and experience so that you can become a well-informed consumer.

If you want to learn more about Merino wool and other outdoor apparel, check us out on the socials below. Or just hang around a bit and read all the other reviews that we have to offer!

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