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The Best Men's Base Layers of 2022

Jan 14, 2024

The best base layers of 2022 are made of high-quality fabrics with technology to keep you warm and dry. These are some of our favorite men's shirts for winter sports in wool, synthetic, and blends.

There are a lot of great choices for long underwear these days. To help you pick the best this season, GearJunkie reviewed and itemized a list by insulation category. When possible, we’ve also identified the country of origin and provided fabric weight in either grams per square meter (g/m²) or microns. Here's the topic breakdown:

One tip before we dive in: Everyone has an internal thermostat. If you tend to run cold, buy warmer. If you find yourself stripping off layers when others are bundled, go lighter.

A proper base layer is the foundation of winter comfort. Odlo's Natural + Kinship Warm crew ($100) is a slim-fitting top, designed with seamless body-mapping technology that wears like a thermal second skin.

Taking pride in the adage "form following function," the body-mapped panels follow the body's contours, eliminating any bagginess or awkward bunching and giving the top a smart look. The variable weave thickness dumps heat through "ventilation zones" where you want it and insulates where you need it.

Made from a merino wool-synthetic blend, the material hits all the marks. It's durable and comfortable, doesn't hold stench, and bounces back after putting it through rigorous paces.

As a whole, the base fits snugly but yields unrestricted freedom of movement that rides friction-free beneath midlayers and outer layers without a hitch.

The N+K Warm has become the underpinning piece for the crew at GearJunkie this winter. We’ve been wearing ours from sunup to alpenglow nights. The fit and feel are phenomenal, the construction is fantastic, and it manages moisture very well. And we can usually get a few uses out of it between washes, which is always a plus.

If you’re looking for a hoodie, Odlo offers a version with a face mask for full-coverage protection. If you are looking to up your cold-weather game, we recommend giving Odlo a look.

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Made from 100% merino wool, the Ibex Woolies 2 bottoms ($135) are premium lower-body base layers. All of the best properties of wool are on display in these pants. They’re moisture-wicking, comfortable, durable, and exceptionally warm.

When fitted properly, these bottoms are form-fitting, wrinkle-free, and effectively seamless. Thanks to their 240g density merino construction, they’re a midweight base layer more than capable of keeping your legs warm in very cold weather.

We wore these bottoms for both skiing and winter rock climbing. In both cases, we remained comfortably warm without ever overheating — even during strenuous uphill hiking. They breathed well and wicked away sweat with ease.

The Woolies are outfitted with all of the key features top-notch base layer bottoms should have. The gusseted crotch offers maximal flexibility and minimal chafing, while the offset seams create a smooth overall feel.

The only downside to these exquisite bottoms is their lofty price tag. Though $135 is a lot to pay for long underwear, the quality and durability of the Woolies still add up to a great value. If you want a full set of Woolies, be sure to also check out the base layer top.

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The guys at GearJunkie have been long-time fans of SAXX's underwear. Fellas, if you don't have a pair, we highly recommend investing. Last season, SAXX released a synthetic ultralight base layer ($58), and we love it.

The material is silky smooth and sports a micromesh that breathes exceptionally well. Hold the shirt up to the light, and you’ll see a tight fishnet weave. This "open pattern" reduces the material's contact with the skin, allowing heat and moisture to rapidly wick away from the body. This doesn't mean it's see-through — it's not. The mesh weaves in a pin-dot pattern that's easy on the eyes.

Paired with its great cut, that weave provides a good amount of mechanical stretch too. No binding, no compression. It moves with you in every direction. And magically, it pulls it off without sacrificing durability.

Wear it alone or layer over it. At $58, the Quest is a wonderful base for those looking for an ultralight synthetic top.

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It's the little things with Patagonia's simple crew ($79) that elevate it to our top award in the midweight base category. The smooth external face slides easily under another layer. On the inside, a diamond grid pattern adds a little stretch and micro pockets to trap heat and wick moisture away.

Two elastic thumb loops keep the sleeves down when overlaying a heavier base without adding bulky material around the wrist. And when you’re done for the day, hang it at the lodge from the cord sewn into the back. The material is treated to keep the backcountry stink from chasing your crew back out into the cold.

Capilene is available in a variety of weights and is an excellent option across the board. It's also incredibly durable. A few of our editors have used the same Capilene shirt for nearly 30 years, and it's still going strong.

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At $250, this top is expensive. But a little backstory helps take the edge off. Kora sources its yak wool directly from Himalayan farms. Whole communities rely on Kora. Farm-to-fashion isn't cheap, but you can feel good knowing your purchase helps support a small community halfway around the globe.

At first blush, the Xenolith comes across as a straightforward, heavyweight top with a deep front zipper. The labeling is discreet, and the stitching is appropriately positioned. But what elevates it to the top of our list is the fabric: a yak-merino wool blend.

Yak wool is uber fine and has a hollow core, making it soft to the touch while boosting warmth (air, trapped in the wool's hollow core, has fantastic insulative properties). The Xenolith is spun with a merino blend. The result is plush and surprisingly stout, but we recommend layering it under a protective shell for activities that have the potential for high abrasion.

Turn it inside out, and you’ll see a mesh liner padding the back and shoulders. Look closer, and you’ll notice it protects a thin layer of Polartec Alpha. Alpha lofts up like down, trapping heat and wicking moisture. Because it's synthetic, it stays warm when wet.

You might think the Alpha liner would make the back a little sweaty while schlepping a load in warmer temps. It's actually thinner than the double wool layered in front. A thinner layer of wool lines the lower arms. The Xenolith smartly fits like an insulated vest with integrated sleeves.

Yes, the Xenolith is over the top for backpacking. But that's not what it's made for. Think mountaineering, ice climbing, downhill skiing — the Xenolith finds its groove in pursuing activity in the dead of winter.

If you’re looking for an alpine-weight base layer (and your card can carry the price), the Xenolith is the best you can buy.

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In the coldest of conditions, only the warmest base layers will do. For harsh winter days, we recommend these top-notch merino bottoms from Smartwool ($110).

Smartwool makes a variety of great base layer bottoms, and the 250s are the thickest and warmest of the bunch. Boasting a fabric weight of 250 g/m², these pants are ideal for activities including winter mountaineering, ice fishing, and sub-zero winter walks with the dog.

Merino wool is naturally hydrophobic, so these pants remain comfortable even if you work up a sweat. We also appreciate the impressive breathability of the 250 Bottoms. Effective thermoregulation is rare among heavy base layers, but these pants offer just the right balance of insulation and ventilation.

A word of caution: These pants take a very long time to dry. In freezing temps, wet base layers can be uncomfortable and dangerous, so plan to keep them out of rain and water. However, when used properly, the Smartwool Merino 250 Bottoms are soft, warm, cozy, and wonderful.

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High-quality base layers can get pretty expensive — and many people are hesitant to pay top dollar for clothing no one else will ever see. While some top-notch base layers justify their price with comfort and performance, others are simply overpriced.

With that said, there are some great budget options on the market too, such as the Sport Long Johns Base Layer ($26) set from MEETYOO.

For less than half of the price of many of the base layer tops on this list, the MEETYOO top and bottom set is comfortable, stretchy, and perfectly suited for active use in mild to moderate winter conditions.

These base layers are made from a thin polyester and Spandex blend and definitely fit into the "lightweight" category. While you shouldn't expect a ton of warmth and heat retention from these, they do provide a layer of simple comfort without restricting mobility.

In warm conditions, we found these base layers capable of wicking sweat without becoming wet and saturated. They’re breathable too, which is much appreciated on the approach trail or the skin track.

Though these no-frills base layers lack the high-tech materials and long-term durability of some other options on this list, they’re effective, simple, and fairly priced.

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When our friends ask for bang for their buck in a base layer, we like to point them to synthetics. They are durable and often a cheaper entry point. But the rub? Over time synthetic begins to stink before it wears out.

L.L.Bean's lightweight crew ($40) is a fitted synthetic crewneck that's been treated with an antimicrobial finish. This gives it a longer shelf life in your wardrobe. It doesn't skimp on technical details either.

The seams are flat-locked and offset, helping them ride more comfortably under a pack. And a pair of thumb loops keep the sleeves down when you decide to layer over it, which it does without any awkward binding or seam rub.

We found L.L.Bean's base layer lineup a great fit and recommend them for folks on a budget, just getting into the outdoors, or who simply want a nice-fitting shirt.

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The Midweight Base Layer Bottoms ($55) from REI Co-op achieve the ideal balance between comfort, function, and affordability. When the temps plummet, these cozy long underwear offer an easy layering solution.

For such a low-bulk bottom, these underpants deliver plenty of warmth. From Fairbanks to Fargo, they’re perfect for everyday use in frigid temps.

For active use such as skiing or alpine climbing, these bottoms are a little too loose-fitting for our liking. The material tends to bunch up, which is fine for walking and lounging but not ideal for technical movement.

The interior texture of these pants feels smooth and silky against the skin, and the low-profile seams minimize discomfort and chafing. For the affordable price of $55, the REI Co-op Midweight Base Layer Bottoms are a solid buy.

Read our full review of the REI Co-op Midweight Base Layers.

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Sheep have it all figured out. Wool is a magical fiber; it doesn't hold a stench, naturally blocks harmful UV rays, and is prized for its ability to stay warm when wet. And unlike your dad's wool shirts, today's wool is much softer to the touch.

At the top of the stack of merino sits Icebreaker. The stalwart brand has converted synthetic enthusiasts into dyed-in-the-wool fans. And we can't stop wearing the Oasis 200 ($115).

Subtle details make the 200 a great choice for buyers looking at wool for the first time. The 200-weight fiber straddles the line between lightweight and midweight that matches the lux merino fiber's ability to adapt to the climate.

The fit is slim but doesn't bind or compress. Flat-locked seams are sewn out of the way. Gusseted arms allow full articulation, and the cuffs at the wrists are minimal. The shirt doesn't have thumb loops, but the material is so smooth, it easily slides under another layer.

The Oasis is intended to be worn next to the skin and layered over. The slim fit reinforces this. And when things heat up, we love the true half-zip that drops to the middle of the chest. It allows more temperature regulation than quarter-length zipper tops that are on the market. And when you want that extra level of protection, the front zips up comfortably like a turtle neck.

Wool tends to be more delicate and can wear out more quickly than a synthetic top like Patagonia's Capilene. But the balance of quality, versatility, and overall comfort makes this our top pick for half-zip tops.

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Let's give a shout-out to our hunters. They spend hours — if not days — quietly waiting in what can be atrocious conditions. Sitka Gear's Core Lightweight ($129) is their foundation piece for the fall's fickle weather.

While Sitka takes aim at the hunting market with its garments, there's a lot of greatness that spills over into other activities. And we found the Lightweight Hoody is a wonderful foundation for our year-round kit.

The lightweight synthetic fibers are treated with Polygiene, preventing odor buildup. The material has a smooth face, and the arms are finished with thumb loops that make it easy to layer over.

The hood wraps around the face and closes under the chin with a half-length zipper. There's no awkward binding or obstruction of view. Inside the hood hangs an integrated neck gaiter that doubles as a face mask. The lightweight material pulls up over the nose when you want it or sits around the neck like a gaiter.

Don't want it in the way? You can slide it behind the neck when putting on the shirt. It's breathable, it's versatile, and it's one of our favorite design features that we’ve seen on a base layer yet.

True to the name, the Lightweight Hoody is a lightweight base. Worn alone, it's up to spring through fall tasks and serves as a solid foundation for trips that dip into winter.

If you’re not a hunter, Sitka offers this next-to-skin base in a variety of solid colors that take the edge off the hook and bullet.

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Comfort-wise, you won't find anything smoother than Ortovox's Rock’n’Wool top ($110). This form-fitted base is spun from a 19-micron Tasmanian merino wool. Luxuriously soft to the touch, it fits like a dream.

The hem runs appropriately long, tucking cleanly away in pants or bibs, and wears untucked equally well. Snug, it works as an extension of the body, which is really what we look for when playing hard outside.

Tapering sleeves narrow down the arms to the wrists with just enough stretch to pull over the forearms if you want. The asymmetric offset sleeve design adds a nice touch of flair.

Straddling lightweight and midweight, the material has a wide thermal range, wearing comfortably next to skin in summer or integrated into your winter layering system.

The Rock’n’Wool Top is one of the best-fitting and softest shirts on the list. We almost awarded this shirt our overall best base layer, but a few minor things knocked it off the podium. Without thumbholes, the sleeves can pull up when donning a second layer.

The seams aren't flat-locked, and the torso panels connect on top of the shoulder, which ride dead center under pack straps. And the asymmetric sleeve design on the left sleeve, while cool-looking, slightly binds around the elbow when pulling it over the arms. And we find 100% wool less durable than fabrics woven with a touch of synthetic.

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Smartwool shares the podium with Icebreaker in terms of merino wool. Its 250-weight base is a touch warmer and has spawned lots of variations in their lineup, including crew neck and hoodie variations.

All of them are fantastic, but we’ve found that year after year, the one we reach for most is the Classic 250 Thermal Merino 1/4-Zip ($115). Our editors have used it for over 3 years as a foundation for cold-weather fishing, backpacking, and general outdoor pursuits. As the day goes on and the sun begins to warm things up, we find the zipper allows us to dump heat to keep us cool.

Like all merino tops, you pay for quality wool. And you need to pay special attention to maintaining your investment (don't iron, don't bleach, line dry).

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A good base layer will keep you warm and dry. A great base layer will do it year after year, across a wide range of activities. We found ourselves reaching for the Ridge Merino's Aspect ($75) shirt both on and off the trail. And for good reason.

With its slightly relaxed fit and contrasting raglan sleeves, the Aspect doesn't shout an affinity for freeze-dried food. Its techie details are subtle.

The 18.5-micron wool is woven with a touch of synthetic. This leverages wool's natural odor-resisting and sun protection properties but has the added benefit of durability and stretch provided by synthetics.

Flat-locked seams are sewn offset from the shoulder. This allows a pack's shoulder straps to ride comfortably, minimizing any chafing. The torso is reasonably longer, adding coverage without draping obnoxiously.

We also loved the hidden horizontal thumb loops. They tuck away cleanly into the shirt's cuff, making them less visible when wearing it around town.

The Aspect is a shirt we think many of us need — a base layer that transitions with an active lifestyle, blending work, workouts, parenting, and chores. This shirt is tough to beat.

Wool-polyester blends are becoming more and more popular. Leveraging the best of both worlds, they’re warm, manage sweat, and dry quickly.

Black Diamond's Solution ($135) uses Nuyarn material, spinning ultrafine merino wool around a synthetic core. We found the materials dry quickly (a reputed five times faster than pure merino fabric, which can hold up to 30% of its weight in moisture), has fantastic mechanical stretch, and hits it out of the park for durability.

While it does contain wool, this base layer feels great against the skin in part due to the flat-lock seams. We’ve worn it for dozens of days and have been repeatedly impressed with this layer for comfort, quick drying, and odor resistance.

The Solution's sleeves are long, with a true pair of thumb loops that wrap around the wrist. Just shy of $140, you pay the price, but this is an exceptional piece for hardworking backcountry enthusiasts.

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Steve Graepel — the author of this guide — has spent the last 10 winters living and skiing in Minnesota. In an ongoing battle to remain warm and comfortable on the slopes, he's made base layers a standard part of his wardrobe.

In addition to frequent skiing, Steve also puts base layers to the test while running and cycling throughout the northern winter.

To complement Steve's personal expertise, half a dozen male editors across GearJunkie's entire staff base weighed in with their favorite base layers for snowsports, daily wear, and much more.

Everyone who plays outside in winter needs base layers, and it's hard to have too many. Start by considering how you play outside.

Are you active, working hard in the backcountry, and needing it to wick and breathe? Or do you need to stay warm on the lift or hunkered over the lake fishing? There's no right or wrong answer, but knowing how you’ll use these layers will help narrow the field.

Technically, base layers feature a range of designs including tank, long-sleeve and short-sleeve tops, hoodies, bottoms, knickers, briefs, and the traditional full-length underpant. In our guide, we focus on the best options for cold weather and the winter season, which are usually long-sleeve tops and ankle-length bottoms.

The fabric blends of base layers include merino wool, synthetic fibers, or a blend of the two. Within those fibers, there are various densities from ultralight to light and midweight and at the far end, heavyweight.

Some tops feature a hood, partial zipper, or thumb holes. Others are tailored with a crew, mock, or turtleneck.

No pockets or belt loops here, these designs are meant to be worn against the skin in a seamless way that's comfortable beneath other midlayers and outer layers across various activities such as hunting, fishing, hiking, skiing and snowboarding, snowmobiling, or working on a farm.

Ultralight base layers are lightweight and form-fitting. The ultralight base layer will prevent heat loss on an autumn day, shun solar radiation when things heat up, or provide that first quick-drying layer against the skin under heavier base layers.

If you want to strip them off altogether, they disappear nicely in a daypack. The downside of the ultralight lineup is they can be fragile. Materials with thinly woven mesh can snag on brush and Velcro tabs.

Lightweight base layers can be worn alone in 30-degree temps or paired with another layer when the mercury dips. A lightweight base layer is your skin's first line of defense against Old Man Winter. During the colder months, we never leave home without one.

Cooler temperatures require a boost to your base. Midweight base layers strike a balance between insulation and wicking power and are the workhorses of cold-weather pursuits that have you on the stop-and-go.

Wear these base layers for cold days or layer them over a lighter base for added versatility for changing weather conditions.

If your activities find you ice fishing, ice climbing, or bunkering down in a snow cave at 5,000 m, an expedition-worthy heavyweight layer is what you’re looking for. The heavyweight isn't used alone; it supplements a lightweight or midweight base layer.

When purchasing a base layer, consider the activities you want to do. High-aerobic activities (like running, ice climbing, and cross-country skiing) require moisture-wicking capability, where lightweight base layers typically shine.

For those who spend long days outside in more leisurely activities (like downhill skiing), a midweight base in merino wool or synthetic materials will serve you well. And it can be the most flexible piece in your cold-weather arsenal.

Merino can suck up to 30% of its weight in moisture. This isn't a bad thing — that water traps heat and keeps you feeling warm. Synthetics hold less than 7% of their weight in sweat, leaving you feeling colder as moisture rapidly evaporates.

Wool will be more expensive and typically require more care and attention. It's typically not as durable as its synthetic counterparts.

On the flip side, polyester fibers can trap stinky bacterial waste, which creates that funk that's hard to wash out. For mountaineers (or those who never change their clothes), do yourself a favor and get a stink-resistant merino or find a brand that includes stink-inhibitors like Polygiene.

Every year we see a slew of new options that leverage synthetic-wool blends with panels of lighter-weight materials. These feel soft and increase the temperature range of the layer.

Most of these base layers are offered in crewneck, quarter-zip, and even with hoods. To crew or not to crew is a personal preference. Some crewnecks can bind around the neck (which is uncomfortable when sucking air on hill sprints).

And it's easier to cool off by dropping the zipper on those days when the sun comes and goes. But we did find ourselves inconspicuously sliding the crewnecks into our work wardrobe. It simply looks less sporty than the zipper tops.

Hoodies are a fickle fit. Some hit it out of the park, and others squeeze awkwardly around the face, limiting your peripheral view. We called out hoodies that fit us well, but we highly recommend you try before you buy any base layer with a hood.

Many of the base layers on the list come with thumb loops. These can make it easier to pull over another layer (you don't have to fish a sleeve back out). They can also block the intense sun and warm the wrists (our vasculature tends to run shallow in the armpits, elbows, and wrists, close under the skin to dump heat).

Like the hoody, these can run the spectrum of effectiveness. We’ve called out the real winners and faulted them where they don't quite measure up.

Base layers — as their name implies — are meant to be worn as the base of your clothing system, next to your skin. If you pile on cotton underwear and a cotton T-shirt under your base layers, you’re negating all the ways a base layer is intended to work. Most base layer bottoms are intended to be worn as long underwear.

A base layer should have a close fit to your body without sacrificing freedom of movement. Some base layers, like Odlo's Natural+ Kinship, fit snugly but shouldn't be restrictive or cut circulation. Others, like Ridge Merino's Aspect, have a relaxed fit.

Base layers should be able to fit nicely beneath a fleece sweater as well as a pair of Carhartt pants or overalls or ski outerwear.

There is no hard line. It comes down to what you can afford and what activities you do. Synthetics are highly durable and high-wicking, and they have some odor-beating technology. They also usually have a lower price tag. While Patagonia's Capilene Midweight Crew is somewhat expensive at $79, we think it's a fantastic value that will last you a very long time.

Merino is less durable, but it has temperature-regulating features that can work in a wide range of weather, combats odors, blocks harmful UV rays, and also wicks well. Merino wool typically costs more than synthetic blends.

What about silk? Silk needs a lot of washing, is very thin, and is not very durable, so we left it off the list. Most of the base layers on this list are a wool blend or polyester-elastane blend.

Equally as important to materials is the weight of the fabric. Most people will do well with a pair of simple midweight base layers. If you’re perpetually cold or doing a sedentary winter activity, grab a pair of heavyweight base layers. If you’re buying base layers to backcountry ski, run in, or for any other intense activity, go light.

If you’re out in extremely cold temperatures, have poor circulation, or tend to be cold-sensitive, consider a heavyweight set like Smartwool's Merino 250. We’ve found it a fantastic blend of temperature regulation and insulation for cold-weather activities like fall and winter fishing.

For all-around recreation and use in average winter temperatures, grab a midweight option like Odlo's Natural + Kinship, Patagonia's Midweight Crew, or the Ortovox Rock’n’Wool.

Cardio-intense activities, like running or cross-country skiing, and warmer winter days are a good time to opt for lightweight base layers like the Black Diamond Solution 150 Merino Crew, SAXX Quest, or L.L.Bean's Lightweight Crew. For better thermal regulation, consider getting the quarter- or half-zip version of the base layer.

For the greatest warmth and protection, layers are the name of the game. You’ll want to wear full underwear base layers, which wick sweat and help manage body heat during high output or laidback activities.

Base layers fit beneath a midlayer — like a fleece or micro-down jacket or synthetic insulation layer — followed by an outer layer, like a shell, that will protect you against the elements from rain to snow or wind.

Depending on the day's activity and climate, you might choose to wear a base layer beneath an outer layer and skip that middle piece of insulation.

Our cold-loving experts found the best winter jackets of 2023 for men and women. We've got something for every budget and style. Read more…

From lightweight liners to extra-warm winter gloves, we tested and found the best gloves to meet every budget, temperature, and winter sport. Check out top picks from Black Diamond, Hestra, Dakine, and more. Read more…

Steve Graepel & Austin Beck-Doss There are a lot of great choices for long underwear these days. Best Overall Top Best Overall Bottom Best Ultralight Top Best Midweight Top Best Heavyweight Top Best Heavyweight Bottom Best Budget Set Best Budget Top Best Budget Bottom Best Half-Zip Base Layer Best Hooded Base Layer Best of the Rest Odlo Natural + Kinship Warm Crew Base Layer Top Odlo's Natural + Kinship Warm crew N+K Warm Fabric weight: Materials: Best Overall Bottom: Ibex Woolies 2 Ibex Woolies 2 bottoms Woolies base layer top Fabric weight: SAXX Quest Long Sleeve Crew synthetic ultralight base layer Fabric weight: Materials: Patagonia Capilene Midweight Crew Patagonia's simple crew Fabric weight: Materials: Kora Xenolith Sweater 2.0 Xenolith Xenolith Fabric weight: Smartwool Merino 250 Bottoms merino bottoms from Smartwool Smartwool Merino 250 Bottoms Fabric weight: Best Budget Set: MEETYOO Men's Thermal Underwear Set Sport Long Johns Base Layer these base layers Fabric weight: Materials: Best Budget Top: L.L.Bean Lightweight Crew L.L.Bean's lightweight crew Fabric weight: Materials: REI Co-op Midweight Base Layer Bottoms Midweight Base Layer Bottoms REI Co-op Midweight Base Layers Fabric weight: Materials: Best Half-Zip Base Layer: Icebreaker Oasis 200 Oasis 200 Patagonia's Capilene Fabric weight: Materials: Sitka Core Lightweight Hoody Sitka Gear's Core Lightweight Lightweight Hoody Ortovox Rock’n’Wool Long Sleeve Ortovox's Rock’n’Wool top Rock’n’Wool Top Fabric weight: Materials: Smartwool Classic Thermal Merino Base Layer 1/4-Zip Classic 250 Thermal Merino 1/4-Zip Fabric weight: Materials: Ridge Merino Aspect Ridge Merino's Aspect Aspect Fabric weight: Black Diamond Solution 150 Merino Crew Black Diamond's Solution Solution's Fabric weight: Materials: Ultralight base layers Fabric weight: Fiber diameter Lightweight base layers Fabric weight: Fiber diameter Midweight base layers Fabric weight: Fiber diameter: heavyweight layer Fabric weight: Fiber diameter: Odlo's Natural+ Kinship Ridge Merino's Aspect Patagonia's Capilene Midweight Crew Smartwool's Merino 250 Odlo's Natural + Kinship Patagonia's Midweight Crew Ortovox Rock’n’Wool Black Diamond Solution 150 Merino Crew