Staying warm this winter starts from the ground up, and weve been testing the best base layers for men all season to pad out your closet. From high-output ski-hill romps to tucking into something warmer to tend the woodstove, weve settled on the top 12 sets of tops and bottoms that will get you through to spring in fine fashion.

　　Its far easier to splurge on a shell jacket or puffy, but baselayers play an important role in your layering, and they can be the key to sustained comfort on the coldest days. If youre seeking layers for active pursuits, its important to purchase a full-body set, like the Ibex Woolies Tech — but dont think youve got to drain your accounts to make it happen. The budget MEETYOO Thermal Underwear Set gets the nod from us as well.

　　Our primary tester of mens base layers is Steve Graepel, an experienced skier, climber, and trail runner based in Idaho. During testing, Graepel wore various base layers in all sorts of winter conditions. From thick heavyweight options to thin, barely there layers, Graepel assessed fit, feel, warmth, durability, and more.

　　In our handy Comparison Chart, we compare the price, materials, pros, and cons of every base layer on our list. Be sure to also check out our comprehensive Buyers Guide, and Price Value sections for help in narrowing in on the best base layers for your needs.

　　Editors Note: We updated this article on October 28, 2024, to add the Brynje Thermo Base Layers — an excellent mesh set with an expedition pedigree — as well as a new Price Value section to explain what youre getting for the money when it comes to base layers.

　　The Best Base Layers for Men of 2024-2025 Best Overall: Base Layers for Men: Ibex Woolies Tech Best Budget Base Layers: MEETYOO Thermal Underwear Set Best Lightweight Base Layers: L.L.Bean Lightweight Base Layers Best Midweight Base Layers: Patagonia Capilene Midweight Base Layers Best Heavyweight Top: Kora Xenolith Yak Merino Wool Mountain Sweater 2.0 Best Heavyweight Bottom: Kora Freedom Yak Wool Base Layer Bottoms Best Expedition Base Layers: Brynje Thermo Base Layer Best Overall Base Layers for Men Ibex Woolies Tech Specs Fabric Weight 180 g/m² Materials 81% Merino wool, 12% nylon, 7% elastane Thermal Category Midweight Fit Semi-fitted Garment Weight 7.3 oz. (top); 5.7 oz. (bottom)

　　Pros Warm majority Merino wool weave Top has baste stitched thumbholes, meaning you can leave them closed, or cut them open for use Fit is a bit looser and more casual Durable stitching, and effectively seamless Cons Pricey Limited seasonal colorways Steve Graepel Made from high-quality Merino wool, nylon, and a dash of elastane for stretch, the Ibex Woolies Tech ($115 each for top and bottom) are premium base layers. If youre after a one-and-done solution, just snag this set. These layers showcased all of wools best properties during our testing: Theyre moisture-wicking, comfortable, durable, and exceptionally warm.

　　When fitted properly, the Tech tops and bottoms are form-fitting, wrinkle-free, and effectively seamless. Thanks to their 180 g/m² density Merino construction, theyre a light-to-midweight base layer more than capable of keeping your torso and legs warm in very cold weather. We wore these layers while skiing and rock climbing across Idaho this winter, and in both cases, we remained comfortably warm without ever overheating — even during strenuous uphill hiking.

　　The semi-fitted fit means you wont feel the squeeze in these base layers (and the top is fashionable enough for wearing around town). The bottoms sport a gusseted crotch that offers maximal flexibility and minimal chafing. The offset seams create a smooth overall feel against the skin. Then theres our favorite detail: the thumb holes come lightly stitched closed, so you can opt to run without or open them up for daily use. Smart.

　　When it comes to Merino baselayers, we tend to prefer a wool-biased blend, and the added 12% nylon and 7% elastane in the Woolies give it more durability compared to full Merino pieces like the Icebreaker Merino Oasis 200 or Ortovox 185 Merino Rock’n’Wool set. While the moisture-wicking ability is a bit better in these layers, we wore holes into them much quicker than the Woolies, and with respect to durability, we think the Ibex layers are a better choice overall.

　　The only downside to these exquisite base layers is their lofty price tag. Though $115 is a lot to pay for a simple long-sleeve top, the quality and durability of the Woolies still add up to a great value. If you go with a full set of Ibex Woolies Tech base layers, your investment will pay dividends over many winters to come.

　　$98 at Ibex Shirt$115 at Ibex Pants Best Budget Base Layers MEETYOO Mens Thermal Underwear Set Specs Fabric Weight N/A Materials 92% polyester, 8% Spandex Thermal Category Lightweight Fit Slim fit Garment Weight 1 lb., 1.6 oz. (set)

　　Pros Knit construction lacks seams Affordable price for a full set Slim fit rides under bulkier winter layers Good portion of elastane and knit construction makes these base layers stretchy and mobile Cons Minimal heat retention No fly in the base layer bottoms Sizing can be a bit tough to nail for some people Steve Graepel High-quality base layers can get pretty expensive — and many people are hesitant to pay top dollar for clothing that no one else will ever see. With that said, there are some great budget options on the market too, such as this nifty set of MEETYOO Mens Thermal Underwear ($29). For less than half of the price of many of the base layer tops on this list, this set is perfectly suited for active use in mild to moderate winter conditions.

　　Made from a knitted polyester and spandex blend, these tops and bottoms definitely fit into the lightweight category. This knitted construction is similar to that seen in other high-end layers like the Smartwool Intraknit or Brynje Thermo Base Layer, and creates a garment with almost no seams to chafe on and an impressive built-in stretch. While you shouldnt 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. Theyre breathable, too, which is much appreciated on the approach trail or the skin track. The 100% synthetic build is to be expected at the price point, and while the stink factor did build up quicker than most we tested, you wont be wearing any holes in these layers prematurely.

　　Though the no-frills (note: no relief fly on these bottoms) Mens Thermal Underwear lacks the high-tech materials and long-term durability of some other options on this list, theyre effective, simple, and fairly priced. Buy them and run them into the ground — theyre cheap enough.

　　$30 at Amazon Best Lightweight Base Layers L.L.Bean Lightweight Base Layers Specs Fabric Weight 130 g/m² Materials 100% polyester Thermal Category Lightweight Fit Slim fit Garment Weight N/A

　　Pros Good value for the money Anti-microbial finish helps fight off the synthetic stink Internal locker loop Thumb holes fit well and keep sleeves in places 1.5 wide stretch waistband and functional fly in bottoms Cons Not the best warmth retention Can be a bit harder to get your hands on Steve Graepel When our friends ask for bang for their buck in a base layer, we like to point them to synthetic materials. Compared to wool, synthetics are durable and more affordable. But the rub? Over time, synthetic begins to stink and eventually wears out.

　　The L.L.Bean Lightweight Base Layers ($40 each for top and bottom) is a fitted base layer system thats been treated with an antimicrobial finish — a necessity, in our opinion. This gives it a longer shelf life in your wardrobe. It doesnt skimp on technical details, either — these base layers could have easily also garnered a Best Value nod as well.

　　At 130 g/m², these base layers are squarely in the lightweight camp, and are best for shoulder season forays or high-output activities where heavier layers might trap extra warmth. The Patagonia Capielene Midweight layers are a bit thicker, so if youre on the fence and feel these might not be warm enough, its an easy pivot to make.

　　The seams are flat-locked and offset, helping them ride more comfortably under a pack. On the crewneck top, 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. Plus, the crewneck top doubles as a nice-fitting shirt for all-season use.

　　The base layer bottoms are equally well made, and sport a wide stretch waistband that keeps them from creeping down during repetitive activities like skiing moguls or chopping firewood. We found L.L.Beans lightweight Base Layers to offer big value for a lightweight base layer set, and we recommend them for folks on a budget.

　　Check Shirt Price at L.L.BeanCheck Pants Price at L.L.Bean Best Midweight Base Layers Patagonia Capilene Midweight Base Layers Specs Fabric Weight 147 g/m² Materials 100% recycled polyester Thermal Category Midweight Fit Slim fit Garment Weight 6.2 oz. (top); 5.8 oz. (bottom)

　　Pros Durable synthetic build Raglan sleeve design keeps seams off shoulders and away from pack straps Wicks moisture well HeiQ Mint odor control finish keeps stink at bay Broad colorway and size options Cons Trim athletic fit doesnt work for all Material will begin to pill with time Steve Graepel It’s the little things with Patagonia’s Capilene Midweight Base Layers ($89 each for top and bottom) that elevate them to our top award in the midweight base layer 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.

　　On the top, 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. These synthetic baselayers benefit from an antimicrobial treatment in the same way that the Helly Hansen baselayers do, but this is the name-brand stuff: HeiQ Mint — which adds an herb-derived treatment.

　　In practice, we noticed that this treatment isnt quite as good as the original HeiQ silver-salt formula, but still much better than untreated synthetics after a hard day sweating into them. Well leave the change on the table for the planet here. Other appreciated aspects of Capilene baselayers are the raglan sleeves on the top, which eliminate seam lines atop the shoulders (and keep them away from pack straps).

　　The equally comfortable bottoms are pleasantly form-fitting and exceptionally stretchy. They are a bit looser-fitting than some other base layer bottoms we tested and land about in the middle between the pajama-like Ibex Woolies and skin-tight Icebreaker Oasis. The broad elastic waistband kept these pants where they belonged all day.

　　While the price of these base layers has gone up $10 each since we first started testing them, Patagonias steadfast Ironclad Guarantee makes them still an easy buy. Repairs needed due to wear and tear can be made at a reasonable charge, which isnt something nearly any other baselayer manufacturer offers. One of our editors has used the same Capilene shirt for nearly 30 years, and it’s still going strong — these base layers live up to the hype.

　　$79 at evo PantsCheck Top price at Patagonia Best Heavyweight Base Layer Top Kora Xenolith Yak Merino Wool Mountain Sweater 2.0 Specs Fabric Weight 240 g/m² Materials 70% Merino, 30% yak (body); 100% Polartec Alpha (lining) Thermal Category Heavyweight Fit Semi fitted Garment Weight N/A

　　Pros Exceptionally warm Merino and yak wool blend Body-mapped insulation is great for active use in very cold temps Comfortable fit Polartec Alpha insulation is top-shelf addition Cons Expensive Not available in bottoms Pull-over design wont be for everyone Steve Graepel At $270, the Kora Xenolith Yak Merino Wool Mountain Sweater 2.0 represents the upper end of the base layer price range. But a little backstory helps take the edge off. Kora sources its yak wool directly from Himalayan farms, and farm-to-fashion isnt cheap, but you can feel good knowing your purchase helps support a small community halfway around the globe.

　　At first blush, the Xenolith seems like a straightforward, heavyweight top with a deep front zipper, much like the Icebreaker Merino Oasis or Smartwool Classic. 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 wools 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 youll see a mesh liner padding the back and shoulders. Look closer, and youll notice it protects a thin layer of Polartec Alpha. Alpha lofts up like down, trapping heat and wicking moisture. Because its 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. Its 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, this top is over the top for backpacking. But thats not what its made for. Think high-altitude mountaineering, ice climbing, downhill skiing — the Xenolith finds its groove in pursuing activity in the dead of winter. If youre looking for an alpine-weight base layer (and your card can carry the price), the Xenolith is the best you can buy.

　　$250 at Kora Best Heavyweight Bottom Kora Freedom Yak Wool Base Layer Bottoms Specs Fabric Weight 230 g/m² Materials 40% Merino, 60% yak (body) Thermal Category Heavyweight Fit Slim fit Garment Weight N/A

　　Pros Very warm Merino and yak wool blend Low profile seams Durable waistband Reinforced fabric panels up the durability Cons Pricey No Polartec Alpha lining as in the base layer top Steve Graepel Like the Xenolith top, the Kora Freedom Yak Wool Base Layer Bottoms ($165) — formerly named the Yushu — are plush, pliable, and protective. Made from a blend of premium yak wool and Merino, these leggings boast the best base layer materials on the market. In our experience, the pants deliver A+ comfort on par with silk pajamas.

　　With low-profile seams and a reinforced crotch panel, the Yushu bottoms are thoughtfully designed without feeling over complicated. Though they do breathe well, we recommend saving these exclusively for the coldest days of the year. The yak wool is super warm, and can cause sweating issues during truly active use.

　　Interestingly, Kora flips the blend on these bottoms, where the Xenolith uses more Merino wool, and the Freedoms use more yak. This makes good sense to us, as bottoms typically dont require the added moisture management of tops, and the added yak wool only increases the cozy feel.

　　Paired with the Kora Xenolith Mountain Sweater, the Yushu Yak Wool base layer bottoms are a fit for folks brave enough to venture out into sub-zero wind chill. If youre headed into unkind elements and plan on really moving, however (a ski across Greenland?), a mesh baselayer like the Brynje Thermos may be a better choice. But for static warmth, the Kora combo is our choice.

　　$165 at Kora Best Expedition Base Layers Brynje Thermo Base Layer Specs Fabric Weight 125 g/m² Materials 80% Merino wool, 20% polyamide Thermal Category Heavyweight Fit Slim fit Garment Weight 5 oz. (top); 5.2 oz. (bottom)

　　Pros Wide temperature range Makes ventilation easy Intelligent padding placement Flexibility Sizing versatility Cons High price tag Relatively hot and clammy without ventilation Limited color options Limited UV protection Steve Graepel Mesh base layers have gone far and wide on some pretty harrowing expeditions, and the Brynje Thermo Base Layers ($105 each for top and bottom) were there from the start. Tenzing and Sir Edmund sported a cotton version of the mesh base layers when they stood atop Everest for the first confirmed summit, and these Merino wool blend versions are even better.

　　Sure, the look is strange, but the performance tells the whole story: The fishnet-like weave captures warmth between the holes in the fabric excellently while still allowing for vapor transfer when sweating heavily. The result is a baselayer that might have a fabric weight of only 125 g/m², but insulates much more like the heavyweights in our review.

　　We took these base layers well out of their comfort zone, as well, challenging them to a 300-mile bikepacking trip that ran headlong into wind and rain, where they still excelled — even outside of their element. The party stopped around the time the sun came out, however, as the black color warmed up quicker than we could shed warmth. But as a layer thatll be beneath others most of the time, this should be a non-issue.

　　One thing to know about mesh base layers like these: youll want to be in good company should you decide to strip down to them when the mercury climbs. While the Womens Super Thermo (that is, 100% polypropylene) does incorporate a few solid modesty panels, the unisex Merino cut does not, making these ideal layers for running when its cold enough to stay bundled up.

　　The price is also a bit high, but not as high as the Kora heavyweight combo weve recommended (and also quite a bit lighter weight overall). When investing in equipment for high latitudes or long trips abroad, spending the extra makes good sense to us in the long run. The Thermo Base Layers from Brynje are made for your next far-flung expedition.

　　Read Review: From Trail to Treadmill, Fishnet Base Layers Are Best: Brynje Thermo Review CHECK PRICE AT BRYNJE Best of the Rest Icebreaker Merino Oasis 200 Specs Fabric Weight 200 g/m² Materials 100% Merino wool Thermal Category Midweight Fit Semi-fitted Garment Weight 7.6 oz. (top); 7 oz. (bottom)

　　Pros Comfortable full-Merino weave Retains warmth when wet Versatile mid-weight fabric Droptail hem protects against breezes Cons Top lacks thumb loops Full Merino will degrade faster than blends Quarter zip adds weight and bulk to the top Steve Graepel Wool is a magical fiber; it doesnt hold a stench, naturally blocks harmful UV rays, and is prized for its ability to stay warm when wet. Near the top of the stack of Merino sits Icebreaker. The stalwart brand has converted synthetic enthusiasts into dyed-in-the-wool fans. And we cant stop wearing the Icebreaker Merino Oasis 200 ($115 for the top, $105 for the bottoms).

　　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, which matches the lux Merino fibers ability to adapt to the climate. This is a 100% Merino set, which means that a) youll certainly pay for it, and b) itll need a gentler hand in use and washing.

　　The fit is slim but doesnt bind or compress. Flat-locked seams are sewn out of the way. Gusseted arms allow full articulation of the torso, and the cuffs at the wrists are minimal. The shirt doesnt have thumb loops — a notable omission that keeps it from getting our full support over other layers like the Ibex Woolies or Patagonia Capilene layers — 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 tops 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 Patagonias Capilene Midweights. But if youve got the dough and want the full measure of advantages that Merino brings to the table, the Merino Oasis 200 set is a good bet.

　　$115 at evo Shirt$105 at REI Pants SITKA Core Merino 220 Baselayers Specs Fabric Weight 220 g/m² Materials Merino wool + nylon blend Thermal Category Midweight Fit Slim fit Garment Weight 11.1 oz. (top); 7.8 oz. (bottom)

　　Pros Merino wool + nylon blend for durability Low profile seams Comfortable Odor resistant Zippered chest pocket Cons Pricey Only one solid colorway for non-hunters Steve Graepel Lets give a shout-out to our hunters. They spend hours — if not days — quietly waiting in what can be atrocious conditions. The SITKA Gear Core Merino 220 Base Layers ($199 for the top, $129 for the bottoms) are an excellent layering foundation for the falls fickle weather.

　　While SITKA takes aim at the hunting market with its garments, theres a lot of greatness that spills over into other activities. And we found the Core Base layers to be a wonderful addition to our year-round kit.

　　The lightweight ArmorSpun Merino wool is airy and breathable, preventing odor buildup. This is nice not only for your hunting partner but also for keeping your profile low on hunts. The material has a smooth face, and the arms of the top are finished with thumb loops that make it easy to layer over. Were not generally fans of chest pockets on base layer tops (as they tend to become buried under other layers), but the inclusion here makes a bit more sense for the sport-specific SITKA layers.

　　True to the name, the Core base layers help to effectively maintain a comfortable core temperature. These midweight layers are ideal for spring and fall tasks and serve as a solid foundation for trips that dip into winter.

　　The high price here is due to the high-percentage Merino weave, but also the fact that you can get the SITKA base layers in a variety of Optifade camouflage patterns — which take a surprising amount of RD to create. If youre not a hunter, SITKA offers the Core Merino 220 base layers in a solid grey Lead colorway.

　　These base layers are pretty niche for hunting use (scope our selection of best Hunting Base Layers while youre here), which keeps them from reaching the top of our lineup, but if thats your jam, its tough to go wrong. We see great utility in snagging a baselayer that matches the camo pattern youve invested in.

　　$199 at Sitka Gear Shirt$129 at Sitka Gear Pants Ortovox 185 Merino RocknWool Base Layers Specs Fabric Weight 185 g/m² Materials 100% Merino wool Thermal Category Lightweight Fit Slim fit Garment Weight 6.7 oz. (top); 6 oz. (bottom)

　　Pros Precise athletic fit Versatile thermal range Comfortable texture Nice snug sleeves on top Cons Seams are noticeable under pack straps Oddly sewn design creates strange stretch patterns No thumbholes on sleeves Steve Graepel Comfort-wise, you wont find anything smoother than Ortovoxs RocknWool Base Layers ($110 for the top and bottoms). These form-fitted beauties are spun from a 19-micron Tasmanian Merino wool. Luxuriously soft to the touch, they fit like a dream.

　　On the top ($110), the hem runs appropriately long, tucking cleanly away in ski pants or bibs, and wears untucked equally well. Both the top and bottoms ($110) function as an extension of the body, which is really what we look for when playing hard outside.

　　We like that the tops 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 RocknWool material has a wide thermal range, wearing comfortably next to skin in summer or integrated into your winter layering system.

　　The RocknWool 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 arent 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.

　　Aside from the slightly funky seams, the bottoms are near-perfect. The RocknWool Base Layers have become our go-to for resort skiing.

　　$110 at REI Shirt$100 at REI Pants Smartwool Classic Thermal Merino Base Layers Specs Fabric Weight 250 g/m² Materials 100% Merino wool Thermal Category Midweight Fit Semi-fitted Garment Weight 10.1 oz. (top), 8 oz. (bottom)

　　Pros Soft, cozy texture Versatile quarter zip for venting Can be worn as a top around town Many different colorways and patterns available Cons Pricey Not immune to developing holes Can be a bit too thick for active pursuits Steve Graepel Smartwool shares the podium with Icebreaker in terms of quality Merino wool. Smartwools 250-weight base layer is tried-and-true and has spawned lots of variations in their lineup, including crew neck and hoodie variations.

　　All of the brands base layer offerings are fantastic, but weve found that year after year, the one we reach for most is the Classic 250 Merino Thermals ($120 for the top, $115 for the bottoms). Our editors have used these for over 3 years as a foundation for cold-weather fishing, backpacking, and general outdoor pursuits.

　　The half-zip top is particularly excellent. 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. The 10 zipper length isnt quite as long as the Kora Xenolith or SITKA Core 220 layers, but it still does an admirable job of cooling the brakes.

　　Like all genuine Merino wool, these base layers arent cheap. Plus, theyre fairly delicate. You need to pay special attention to maintaining your investment. For most folks, we tend to recommend the more durable Ibex Woolies as theyve got a bit of nylon and are just a bit cheaper. Youll miss out on the quarter-zip on the top, however, and if the added venting option appeals to you, the Classic 250 layers can be a great option.

　　$120 at REI Shirt$115 at REI Pants Ridge Merino Aspect Midweight Base Layers Specs Fabric Weight 180 g/m² Materials 84% Merino wool, 16% nylon Thermal Category Lightweight Fit Semi-fitted Garment Weight 8.3 oz. (top); 6.6 oz. (bottom)

　　Pros Good value for Merino wool Versatile cut Low-profile seams Hidden thumb loops Cons Long hem wont suit everyone Jack of all trades, master of none Steve Graepel 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 Aspect Base Layers ($75 for the top, $70 for the bottoms) both on and off the trail. And for good reason.

　　With its slightly relaxed fit and contrasting fitted sleeves, the Aspects techie details are subtle. The 18.5-micron wool is woven with a touch of synthetic. This boosts wools 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 packs shoulder straps to ride comfortably, minimizing any chafing. On the shirt, the torso is reasonably longer, adding coverage without draping obnoxiously.

　　We also loved the tops hidden horizontal thumb loops. They tuck away cleanly into the shirts cuff, making them less visible when wearing it around town. The bottoms are simple and effective.

　　The Ridge Merino Aspect layers easily transition to suit an active lifestyle, blending work, workouts, parenting, and chores. For the price, theyre tough to beat.

　　Check Shirt Price at Ridge MerinoCheck Pants Price at Ridge Merino Mens Base Layers Comparison Chart

　　Layering up in a ski hut before a big day out; (photo/Xander Bianchi) The GearJunkie testing team has tested scores of base layers over the decades, from lightweight sleeping sets for summer backpacking to polar-weight onesies for deep expeditions. Guide author Steve Graepel compiled this guide in 2021 with an initial slate of 20 worthy base layers, and our team has tracked the trajectory of base layers since then — testing more than 50 sets since then.

　　To narrow in on the best base layers for men today, we researched, obtained, and sent these layering essentials out to a diverse team of outdoors athletes, trail crew leaders, and iterant fisherfolk — to name a few. Testing feedback is reported and compiled in addition to Graepels own field tests, and we make recommendations based on the whole picture.

　　The beauty of a good base layer is in its versatility — we often use the same sets for skiing, winter camping, and early-morning fishing. Because of this, we aimed to use them as part of our layering systems in a variety of activities, and weve gone pretty far flung doing so.

　　Field Testing We have taken these baselayers on months-long thru-hikes of the Pacific Crest Trail, heli-skiing in the Monashees of British Columbia, and across 300-mile bikepacking trips across the rural U.S. Longevity is a big deciding factor when it comes to recommending a base layer, so we wear these sets for entire seasons of use before landing on the final say.

　　Were looking for piling and snags, poorly running zippers, and fabric stretching, and any base layer that doesnt make the cut doesnt make the guide. We look at breathability when really using these layers under load, and at static warmth when worn solo to shore up the rating on a sleeping bag.

　　Finally, whenever possible we also have multiple testers in the same sets of baselayers, giving us the best possible understanding of these base layers when it comes to all body types. Our female testing team members have also pulled together a Best Base Layers for Women guide.

　　Base layers for ski or split touring need to be breathable enough for the way up, but warm enough for the ride down; (photo/Erika Courtney) Bench Testing Beyond the real-deal testing, we also take a deeper look at these base layers as pieces of apparel, and consider the general fit, ease of laundering, and long-term durability in our overall impressions. Because base layers are know to sometimes accumulate a funk, we also, yes, conduct smell tests to relate the performance of Merino wool versus synthetics, and understand how well antimicrobial treatments work.

　　Why You Should Trust Us 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, hes made quality 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. While actively testing base layers, Steve pays careful attention to overall comfort, warmth, and durability. Other more subtle factors also play a role in the evaluation process. We note the quality and feel of the seams, the breathability of the fabric, the tendency for piling, and much more. Overall, weve tested over two dozen base layer styles over three-plus winter seasons.

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

　　Buyers Guide: How to Choose the Best Base Layers

　　Some base layers have fitted hoods — a great asset in certain conditions; (photo/Sean McCoy) 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.

　　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.

　　Styles of Base Layers 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 underpants. 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.

　　Base layer bottoms dont have pockets or belt loops. These pants are effectively long underwear — theyre 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.

　　Fabric Weights 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. The L.L.Bean Lightweight Base Layers are a weight we can wear all summer long as sleep clothes, and breathe quite well.

　　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.

　　Fabric weight: 80-140 g/m² Fiber diameter: 17.5 microns Lightweight base layers can be worn alone in 30-degree temps or paired with another layer when the mercury dips. A lightweight base layer like the Ibex Woolies Tech is your skin’s first line of defense against Old Man Winter. During the colder months, we never leave home without one.

　　Fabric weight: 140-190 g/m² Fiber diameter: 17.5-18.5 microns 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. The Patagonia Capilene Midweight Base Layers had a broad range of temperatures we felt comfortable wearing them in, and are great all-around options.

　　Fabric weight:190-250 g/m² Fiber diameter: 21.0 microns 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. The Kora Xenolith Mountain Sweater 2.0 and Freedom Bottoms add a lot of static warmth to a layering system.

　　Fabric weight:250 g/m² and heavier Fiber diameter: 24.5 microns

　　No need for outer layers on a warm spring day; (photo/Steve Graepel) Activity and Use 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 vs. Synthetic 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 is more expensive and typically requires more care and attention. Its also typically less durable than its synthetic counterparts.

　　On the flip side, polyester fibers can trap stinky bacterial waste, creating a hard-to-wash funk. 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 or HeiQ, like the Patagonia Capilene Midweight Base Layers.

　　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.

　　Cut and Length 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.

　　Hoods and Thumb Loops 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 dont 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. The Ibex Woolies Tech uses a novel approach here, and runs a very light stitch across their thumb holes, meaning you can snip them open for use, or leave them closed if you dont find them useful. We’ve called out the real winners and faulted them where they don’t quite measure up.

　　The GearJunkie team testing an assortment of winter layering systems in Crested Butte, Colo.; (photo/Eric Phillips) Price Value Base layers might not get all the hype, but that doesnt mean you should settle for any old set. Theres a wide range of applications and prices when it comes to these layers, and you should consider a few things before deciding on a set: What will you be wearing these base layers for most? How warm will you need to be for the coldest part of the day? Or how sweaty might you get?

　　Budget Budget base layers are generally going to be synthetic blends instead of Merino wool, but they do retain some good warmth and breathe well enough (certainly lighter fabric weights). These materials can hold onto odor more than Merino wool pieces, so its not uncommon to see antimicrobial treatments applied to cut down on the funk.

　　Expect to pay around $30-40 for each top and bottom in the budget range, but some great values are out there, such as the $29 MEETYOO Men’s Thermal Underwear Set. Youll give up the benefits of a fly in the pants, but we were still impressed at the stretch and performance for the price. The L.L.Bean Lightweight Base Layersare a bit more at $40 each but include features seen in pricier layers such as thumb loops, a locker loop, and a broad waistband.

　　Mid-Tier Bumping up to $100 (per top or bottom) gets you into some much nicer stuff. Merino wool is common, along with blends of nylon or elastane to increase durability and stretch. Youll also begin to see higher-quality sewing techniques used, such as flat-locked stitches or raglan sleeves that move the seam lines from above the shoulders.

　　The Ibex Woolies Tech($115 each for top and bottom) is all of this in a midweight set that works for a huge number of activities. The high percentage of Merino wool keeps them warm, breathable, and stink-free over the long run, and theyve got small details such as the baste-stitched thumbholes, which can be opened up or left closed depending on the user.

　　Premium Paying over $200 for a base layer means its pretty premium, and these may incorporate boutique fibers such as the Himalayan yak wool used in the Kora Xenolith Yak Merino Wool Mountain Sweater 2.0 ($270). These might also use proprietary camouflage prints for hunters who want to complete an outfit, like the SITKA Core Merino 220 Base Layers ($199 for top, $129 for bottoms). Know that the biggest thing youll be getting for your extra money is durability, which can mean buying fewer base layers in the long run.

　　Frequently Asked Questions How should you wear base layers? 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.

　　Should a base layer fit tight or loose? A base layer should have a close fit to your body without sacrificing freedom of movement. Some base layers, like Patagonias Capilene Midweights, fit snugly but shouldnt be restrictive or cut circulation. Others, like Ibexs Woolies, have a more relaxed pajama-like 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.

　　How do you choose the right fabric for your base layers? There is no hard rule. 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 Patagonias Capilene Midweight layers are somewhat expensive at $79 each, we think its 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.

　　What is a good base layer for cold weather? If you’re out in extremely cold temperatures, have poor circulation, or tend to be cold-sensitive, consider a heavyweight set like Smartwools Classic Thermal Merino layers. Weve 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 Patagonias Midweights, or the Ortovox RocknWool.

　　Cardio-intensive activities, like running or cross-country skiing, and warmer winter days are a good time to opt for lightweight base layers like L.L.Beans Lightweight Base Layers. For better thermal regulation, consider getting the quarter- or half-zip version of the base layer.

　　What is the best layering system for winter activities? 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.

　　The Best Winter Jackets of 2024 Our cold-loving experts found the best winter jackets of 2024. Weve got something for every budget and style.

　　The Best Synthetic Insulated Jackets of 2024-2025 We tested the best synthetic insulated jackets from Arc’teryx, The North Face, Patagonia, and more to help you find the best option for your needs and budget.