There’s no such thing as bad weather – only unsuitable clothing.
For outdoor lovers, this is undoubtedly true. Having the proper clothes to keep you warm – or lack thereof – will easily make or break a cold-weather trip or adventure.
There’s so much to see and do in chilly conditions. From countless activities – like skiing and hiking – to the incredible colder-climate destinations there are to discover – like Scandinavia and Patagonia; you can enjoy them all by simply having the right thermal wear for top comfort and performance.
Luckily for us adventurers, there are a TON of quality options out there to cover all of your bases.
So, I’ve gathered all of my top recommendations for the best base layers out there to help point you in the right direction. There is a lot to choose from, but hopefully, you’ll find these base layer reviews helpful.
looking for cheap base layers? The best mens base layers? Heavyweight, lightweight, top, bottoms etc etc… we’ve got it all!
So, let’s get to our top rated base layers!
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Quick Answer: Best Base Layers for Men and Women
- Icebreaker 200 Oasis Crew Top – Best Base Layer Overall (Tops)
- Smartwool Classic Thermal Merino Crew Base Layer Top – Best Base Layer Overall for Women (Tops)
- Icebreaker 200 Oasis Base Layer Leggings – Best Base Layer Bottoms (Men)
- Smartwool Intraknit Merino 200 Base Layer Bottoms – Best Base Layer Bottoms (Women)
- Patagonia Capilene Midweight Crew Base Layer Top – Best Base Layers for Travel
- Icebreaker 260 Zone Half-Zip Base Layer Top – Best Base Layer for Extreme Cold
- Smartwool Merino Classic Thermal Base Layer Long-sleeve Top – Best Everyday Layer
- REI Co-op Midweight Long-Sleeve Shirt – Best Base Layer for Thru-Hikers
- REI Co-op Merino Midweight Bases Layer Half-Zip Top – Best Merino Base Layer Under $90
Icebreaker 200 Oasis Crew Top
- Price > $105
- > Insulating and comfortable
- > Sun protective with no stink
Smartwool Classic Thermal Merino Crew Base Layer Top
- Price > $115
- > Provides 50+ UPF protection
- > Longer waist that won’t ride up
Icebreaker 200 Oasis Base Layer Leggings
- Price > $105
- > Quick-drying
- > Suitable for snow sports or everyday use
Smartwool Intraknit Merino Base Layer Bottoms
- Price > $130
- > Intranet design for a sportier feel
- > Breathable for comfort
Patagonia Capilene Midweight Crew Base Layer Top
- Price > $79
- > Inexpensive
- > Odor control
Icebreaker 260 Tech Half-Zip Base Layer Top
- Price > $135
- > Lighter panels under the arms and back
- > Half-zip front for added temperature regulation
Smartwool Merino Classic Thermal Base Layer Long-sleeve Top
- Price > $115
- > Lightweight
- > Doesn’t need to be washed often
REI Co-op Midweight Long-Sleeve Shirt
- Price > $54.95
- > Silk feels supple and comfortable
- > Ultra-lightweight for a variety of activities
REI Co-op Merino Midweight Bases Layer Half-Zip Top
- Price > $59.95
- > Wool fabric
- > Half-zip allows for extra ventilation
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Join REI Today!- Best Base Layer Overall (tops)
- Icebreaker 200 Oasis Crew Top
- Rocky Stratum Sent IQ Hoodie
- Best Base Layer Overall for Women (tops)
- Smartwool Classic Thermal Merino Crew Base Layer Top
- Best Base Layer Bottoms (Men)
- Icebreaker 200 Oasis Leggings
- Best Base Layer Bottoms (Women)
- Smartwool Intraknit Merino Base Layer Bottoms
- Best Base Layer for Trekking
- Black Diamond Lightwire Long Sleeve Technical T-shirt
- Best Base Layer for Travel
- Patagonia Capilene Midweight Crew Base Layer Top
- Best Base Layer for Extreme Cold
- Icebreaker 260 Tech Half-Zip Base Layer Top
- Best Everyday Layer
- Smartwool Merino Classic Thermal Base Layer Long-sleeve Top
- Best Base Layer for Thru-Hikers
- REI Co-op Midweight Long-Sleeve Shirt
- Best Merino Base Layer Under $90
- REI Co-op Merino Midweight Bases Layer Half-Zip Top
- Best of the Rest: More of the Best Base Layers (Tops)
- Best of the Rest: More of the Best Base Layers (Bottoms)
- How to Choose the Best Base Layers – Buyers Guide 2025
- How We Tested The Best Base Layers
- FAQ about the Best Base Layers
- Buy Us a Coffee!
Best Base Layer Overall (tops)
Really warm and ultra comfy – I have been using this one for years and love it.
- Price: $105
- Best use: Snowsports
- Fabric: Merino wool
- UPF rating: 20
- Underwear weight: Medium
This base layer is so warm and comfy; I’ve been using this one for years and love it. I’ve never had to deal with chafing because it’s functionally designed with flat stitching and offset shoulder seams.
The Oasis is made of merino wool, and when it comes to warmth, you can’t beat a merino wool base layer. It’s soft with no itchy feeling at all. It’s awesome at wicking away moisture and keeping your body temperature regulated. The best part is that wool is naturally odor-resistant. I work up quite a sweat on the slopes, and I’m always impressed at how dry – and not stinky- I am every time.
Although it’s on the pricier side, it’s been worth every penny. It’s lasted a long time and has never failed me – definitely worthy of my top pick as the best base layer overall. If you wear this under a good quality winter jacket, you’ll be good against the next ice age!
The team just loved how comfortable and warm this base layer was as well as how well this thing washes time after time. They also felt that the sizing and fit were great and the base layer wasn’t too tight or loose.
- Insulating and comfortable
- Sun protective with no stink
- Expensive
- Price – $78
- Best Use – Hunting/Fishing
- Fabric – Polyester
- UPF Rating – 20
- Underwear Weight – Medium
The Rocky Stratum Scent IQ Hoodie was primarily designed for hunters and outdoor enthusiasts who value stealth and comfort. But it’s also suitable for travel and day to day use if you can rock the camo design!
Featuring advanced Scent technology (at a great price), this highly affordable hoodie helps neutralise odours, giving you a tactical advantage in the wild and on the road when laundry days can be few and far between. While I like to wear it on its own, it also makes a great base or mid layer on account of its soft and warm insulation.
Its lightweight, breathable fabric ensures all-day comfort, while the moisture-wicking material keeps you dry during high-intensity activities. In summary whether you’re hunting or exploring the outdoors, the Stratum Hoodie offers a perfect blend of performance and comfort.
Best Base Layer Overall for Women (tops)
Smartwool Classic Thermal Merino Crew Base Layer Top is our pick for best base layer overall for women (tops)
- Price: $115
- Best use: Multisports
- Fabric: Merino wool
- UPF rating: 50
- Underwear weight: Medium
With sculpted sides for enhanced fit, the Smartwool base layer was designed specifically for women and delivers on every front. It’s super comfortable and feels soft and warm against even the most sensitive skin.
It’s the best base layer for women because it’s also versatile; it can easily be used as thermal underwear for extra warmth or on its own as comfy, practical performance gear. Smartwool Merino fabric adjusts to your body temperature, so you don’t have to worry about overheating either.
And ladies, you’ll love that you can wear this thing multiple times without needing to wash it. The wool fabric makes this base layer odor-resistant and stink-free. What more could you ask for?
The team here loved how comfortable this base layer was and just how light yet warm it felt to use. They loved that it didn’t restrict them when layered up when they were climbing or skiing. They also find it hardwearing and love how well it washed over the years.
- Made with versatile, itch-free merino wool for a variety of uses
- Provides 50+ UPF protection
- Longer waist that won’t ride up
- Pricey
Best Base Layer Bottoms (Men)
Top pick for the best base layer bottoms (men) is Icebreaker 200 Oasis Leggings
- Price: $105
- Best use: Multisport
- Fabric: Merino wool
- UPF rating: 20
- Underwear weight: Medium
Pair these leggings with the Oasis crew top, and you’ve got yourself one awesome set of top-notch long johns. Not only will these keep you warm, but you can count on no-itch, breathable comfort every time. Everything from Icebreaker’s socks to outerwear has gotten fabulous reviews from our team.
I love the slim fit and how lightweight they are. There’s no restriction in movement, and they give you the perfect amount of snugness – so comfy. They feel great under shell ski pants, softshell pants, or even regular clothing.
If you’re looking for the best thermal underwear for a variety of activities and temperatures, this is it. The wool fabric regulates your body temperature, so there’s no overheating or clammy feeling. Definitely the best baselayer bottoms out there.
The team felt these were their best men’s base layer bottoms for a couple of reasons. Firstly was that they add very little bulk and don’t feel bunched up or restrictive when hiking or climbing. Secondly, they found they didn’t get too hot whilst wearing them for more strenuous activities due to their breathability.
- Quick-drying and moisture-wicking for all-day comfort
- Suitable for a range of applications from snow sports to everyday use
- May run short for taller men
- Pricey
Best Base Layer Bottoms (Women)
Included in our top pick for best base layer bottoms (women) is Smartwool Intraknit Merino Base Layer Bottoms
- Price: $130
- Best use: Multisport
- Fabric: 52% wool/45% polyester/2% elastane/1% polyamide
- Underwear weight: Lightweight
If comfort, fit, and warmth are what you’re after, the Smartwool Intraknit are the best baselayer bottoms for you. The knit structure moves with your body and gives your legs the perfect warm hug, whether you’re outside skiing or out and about on a cold day.
You’ll stay nice and dry with appropriately-placed mesh ventilation. The Merino sports yarn is fantastic because it combines the best of merino wool and polyester for a winning set of thermal underwear that’s both durable and quick-drying.
Oh, and they look cool too. Even if you wear them mostly underneath an outer layer, the geometric mesh design makes for a nice-looking pair of tights. Long underwear that’s both functional and fashionable? Yep, you heard right.
Our team felt these were the best base layer bottoms for women partly due to how cool they look. They loved the unique colourways and design, which along with the thickness of these pants, make them perfect for wearing on their own as well as a base layer. They were also super happy with the inclusion of articulated knees in the design.
- Intranet design for a sportier feel
- Breathable for comfort even on warmer days
- Versatile use for everyday activities or snow sports
- May run small for taller women
- No UPF protection
Best Base Layer for Trekking
Black Diamond Solution 150 Merino Baselayer Crew is our pick for the best base layers for trekking
- Price: $80
- Best use: Multisport
- Fabric: Non-Mulsed Merino certified wool
- Underwear weight: Medium
The Solution 150 Merino Baselayer keeps you warm, dry and in peak condition no matter where your travels take you. Designed for rigorous sports and high-intensity trekking, you can be assured that it will adapt to anything you can throw at it.
Worn on its own or as part of a layering system, the Solution 150 Merino Baselayer is the ideal way to keep your body temperature up when travelling light your focus. The innovative shoulder panel is also designed with comfort in mind when on the trails making sure it doesn’t rub when wearing a backpack. Combined with the anti-chafing flatlock stitching you’ll hardly know you’re wearing it.
Featuring NuYarn’s patented stretch Merino wool technology, it offers superior thermoregulation and moisture management that is exclusive to Black Diamond. The unique fabric is also some of the strongest on the market meaning once you make the investment, your new baselayer is going to stay loyal for years to come.
Add to its superior odour-eliminating technology and you’ve got one of the best base layers on the market. Sure, it’s also one of the most expensive but you get what you pay for.
- Breathable and quick-drying
- Designed to be super comfortable with a backpack
- Keeps odour at bay
- Expensive
Best Base Layer for Travel
Patagonia Capilene Midweight Crew Base Layer Top is our pick for the best base layers for travel
- Price: $79
- Best use: Multisport
- Fabric: Recycled polyester
- Underwear weight: Medium
When you’re packing for any sort of trip, the more multi-functional your items are, the better. That’s why Patagonia’s Capilene top is the best base layer for travel. It’s got all the features you need to make it a great option as top thermal wear for extra warmth or by itself for everyday use.
It’s quick-drying and moisture-wicking, so you don’t have to worry about feeling clammy when layered underneath other clothing or feeling sticky in humid weather if you’re wearing it on its own. It will hold up for pretty much any type of activity you decide to tackle on your travels. It’s one of Patagonia’s best base layers for a reason.
We all know what a pain it can be to do laundry while traveling, so you’ll appreciate the Capilene base layer’s HeiQ fresh odor control. So basically, less washing with no added stench. It’s a win-win.
Our team felt this was their best budget base layer for those looking for something of the mid-weight variety due to its incredible versatility and hard-wearing construction. The design also means it can be worn as an outer layer too if things start to heat up or you need protection from the sun. Combined with one of Patagonia’s winter jackets, it’s a winning combination.
- Breathable and quick-drying for comfortable travel daily wear
- Odor control for less washing while on the road
- Inexpensive
- No UPF protection
Best Base Layer for Extreme Cold
Our top pick for the best base layer for extreme cold is Icebreaker 260 Tech Half-Zip Base Layer Top
- Price: $135
- Best use: Snowsports, Multisport
- Fabric: merino wool
- UPF rating: 35
- Underwear weight: Heavy
If you’re no stranger to snow, ice, and extremely cold weather conditions, you’ll want to gear up against the elements with the Icebreaker 260 Tech half-zip base layer. This thing is really warm with a heavyweight layer, but is built with stretchy fabric and mesh panels that make it breathable and easy to move in.
The half-zip collar is great to have for quick release of extra heat and built-in thumbholes help keep your hands toasty. Even in the coldest conditions, rigorous activity can really make you sweat, but the moisture-wicking material keeps you warm and dry.
Speaking of sweat, this heavyweight base layer is amazing at keeping you odor-free. You can go days without washing it and still have a fresh base layer to put on as often as needed. It’s a clear winner.
The TBB team feels this is their best heavyweight base layer due to just how warm and cosy it feels. They also love the half zipper meaning that they could easily cool down if things did start to heat up. The team felt it was also versatile enough to be worn over the top of a thinner and lighter layer if extra warmth is needed.
- Half-zip front for added temperature regulation
- Lighter panels under the arms and back for quick drying during intense activity
- Can be used on its own for cold weather running or other sports
- No XS small option for smaller builds
- Expensive
Best Everyday Layer
Smartwool Merino Classic Thermal Base Layer Long-sleeve Top is our top pick for best everyday layer
- Price: $115
- Best use: Snowsports, Multisport
- Fabric: 87% merino wool/13% nylon
- Underwear weight: Light
If you want to have just one go-to, year-round base layer, then the Smartwool Merino Classic Thermal is the way to go. It’s lightweight with the temperature control versatility of merino wool, making it ideal for the not-so-extreme cold – like for spring skiing.
The Merino Classic Thermal will keep you warm and comfy, but – thanks to its lightweight and moisture-wicking material – it can also be worn in warm weather to give your arms extra protection. For outdoor cycling, trekking through brush, or on mosquito-heavy days, having arm coverage can be really helpful.
You’ll find this base layer to be a reliable, multi-use article of clothing that you’ll be happy to have in your wardrobe. For its quality, it’s great value for the money if you’re looking for a budget merino wool base layer.
The team found this base layer to be comfortable enough to sleep in on camping trips or cold-ass hostels! The odour-wicking capabilities of the top meant they could wear it for a good few days in a row without it becoming stinky! They also found it to be super versatile for most backpacking trips, protecting both from the moderate cold as well as harmful rays.
- Lightweight and versatile for all-season use
- Doesn’t need to be washed often and stays fresh with no stink
- Available in a variety of colors
- No UPF protection
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Best Base Layer for Thru-Hikers
The Best Base Layer for Thru-Hikers on our list is REI Co-op Midweight Long-Sleeve Shirt
- Price: $54.95
- Best use: Multisport
- Fabric: silk
- Underwear weight: Ultralight
This synthetic construction is a favorable alternative material to a merino wool base layer. For thru-hikers looking for a breathable, ultralight, yet warm base layer – that won’t break the bank – consider choosing this one. This REI brand long underwear shirt is lightweight, cheap, and will do the job.
The best thing about the fabric is how smooth and comfortable it is. You’ll love how soft it feels on your skin! And despite its weight, you’ll be surprised how warm it keeps you. It can easily be worn underneath sports clothing, thicker layers, or everyday streetwear for an extra toasty feel.
For anyone who’s averse to wool – whether due to personal taste or budgetary reasons – synthetic is a good way to go. You’ll probably find yourself using it more than you thought.
If you’re looking for a cheap base layer, our team felt this was the best out there. The material made sure it was super soft and comfortable as well as being as light as possible. They said they couldn’t even feel like they were wearing it meaning they never felt bunched whilst layered up.
- Ultra-lightweight for a variety of activities, including everyday use
- Fabric feels supple and comfortable for all-day wear
- Inexpensive
- Too sheer to be worn on its own
- Delicate fabric requires extra care when washing
Best Merino Base Layer Under $90
REI Co-op Merino Midweight Bases Layer Half-Zip Top is our pick for best merino base layer under $90
- Price: $59.95
- Best use: Multisport
- Fabric: Merino wool
- Underwear weight: Midweight
I personally am a big fan of merino wool for base layers. Nothing can beat it when it comes to performance for cold-weather activities. But, let’s face it, it’s pricey. Luckily, there’s an incredible 100% merino wool half-zip top option for under $90. That’s quite a bargain!
This baselayer top is super warm, isn’t at all scratchy, and is naturally moisture-wicking and odor-resistant. You can sweat as much as you want, and there’s no need to worry about a wet shirt that feels cold and damp against your skin – or stinky. If you happen to need a little extra ventilation to cool down, just pull down the front half-zipper and let some air in.
It works great as a base for very cold conditions or on its own for milder climates. For a basic, go-to base layer at an affordable price, you can’t go wrong with this REI Merino midweight top.
Our team felt this REI top was the best midweight base layer on the market. It was ideal for them to layer up on colder days but equally, it worked well as a stand-alone when things started to warm up. The 1/4 length zipper also came in handy for those days that start off cold and end up warm in the afternoon.
- Half-zip allows for extra ventilation when needed
- Wool fabric naturally wicks away sweat and resists odors
- Inexpensive
- Only available in two colors
- Delicate fabric requires extra care when washing
Best of the Rest: More of the Best Base Layers (Tops)
Icebreaker 260 Tech Half-Zip Base Layer Top
If you need a heavyweight base layer for skiing or other extreme-cold activities, this is one warm and sleek-looking top. Icebreaker products provide superior performance with their BodyfitZONE™ construction that includes stretchy jersey material with merino mesh panels in all the right places. It’s snug, comfortable, and warm!
The long front half-zipper is a bonus too. If you like being able to ventilate a bit to cool down, the zipper option is key. And like all merino wool products, you can wear this shirt for days in a row without washing and it will still feel fresh and odor-free.
The team were big fans of the strategically placed mesh panels on this base layer which made it ideal for cold weather sports like snowboarding and winter climbing.
Odlo Men’s Active Warm Eco Baselayer Top with Face Mask
This is an awesome option if you’re looking for a base layer with an integrated face mask. Not only will you keep your torso extra warm with its 50% wool content, but you’ll have easy access to protect your head against the frosty elements as well.
When you have no need for the face mask, the base layer top looks like a sleek turtleneck. It’s versatile and hugs the body in all the right places. Overall, a solid choice.
For those on the TBB team wanting a little extra protection from the biting winds, often whilst skiing, climbing or biking, the addition of the hood on this base layer was a game changer. They loved how easily it fit underneath a helmet without restricting their views and just how much warmer it kept them.
Smartwool Merino Sport Hoodie
Some of us really enjoy having integrated head coverage that provides instant access to extra warmth – making the hoodie a perfect choice. As far as a cool-looking, high-quality, and thermally-superb base layer, you can’t do better than this Smartwool hoodie.
Plus, it’s made of 100% Merino wool, giving it all this fabric’s benefits – breathable, moisture-wicking, and odor-resistant. If you’re the hoodie type, this one’s for you.
Like the Odlo, the team were once again thankful for the inclusion of a hood on this base layer. They felt the fact it was made from Merino wool really pushed it ahead of it though as it was incredibly breathable for those more action-packed winter days.
Best of the Rest: More of the Best Base Layers (Bottoms)
Under Armour ColdGear Base Layer Bottoms
If you prefer a base layer with more compression, these Under Armour bottoms do the trick. They’re warm, inexpensive, and super comfortable – especially for running – but work great for any other type of workout or sport.
The compression feels snug but also lightweight enough to give your legs just the right amount of energy for increased performance. They’re made of 82% polyester/18% elastane and are treated with an antimicrobial, so you don’t have to deal with excessive odor, which is a definite plus.
Under Armour are a classic brand when it comes to base layers and our team is big fans. They prefer them when it comes to sports and fitness where they need additional compression as well as freedom of movement. They often wear them for winter runs and gym sessions and find them comfortable, stretchy and providing the perfect amount of warmth.
Patagonia Capilene Midweight Base Layer Bottoms
This base layer is another solid choice for keeping your legs warm in colder conditions – whether for layering underneath a shell for hitting the slopes all day or wearing on its own on a cold winter’s day.
You’ll stay dry and comfortable with the soft fabric that stretches with your body and yarn construction that maximizes wicking performance. At an affordable price, these Patagonia midweight base layer bottoms are a smart way to go.
A women’s version is also available.
Patagonia is a favourite brand amongst our team and these long John’s didn’t disappoint. They love how thin the material feels whilst still offering a great level of protection. It meant they were even able to wear them underneath a pair of jeans without being bunched up.
Now, you could spend a fat chunk of $$$ on the WRONG present for someone. Wrong size hiking boots, wrong fit backpack, wrong shape sleeping bag… As any adventurer will tell you, gear is a personal choice.
So give the adventurer in your life the gift of convenience: buy them an REI Co-op gift card! REI is The Broke Backpacker’s retailer of choice for ALL things outdoors, and an REI gift card is the perfect present you can buy from them. And then you won’t have to keep the receipt. 😉
Buy on REI!| Name | Fabric | UPF | Price |
|---|---|---|---|
| Icebreaker 200 Oasis Crew Top | Merino wool | 20 | $105 |
| Smartwool Classic Thermal Merino Crew Base Layer Top | Merino wool | 50 | $115 |
| Icebreaker 200 Oasis Base Layer Leggings | Merino wool | 20 | $105 |
| Smartwool Intraknit Merino Base Layer Bottoms | 53% wool/45% polyester/2% elastane/1% polyamide | Not Available | $130 |
| Patagonia Capilene Midweight Crew Base Layer Top | Recycled polyester | Not Available | $79 |
| Icebreaker 260 Tech Half-Zip Base Layer Top | merino wool | 35 | $135 |
| Smartwool Merino Classic Thermal Base Layer Long-sleeve Top | 87% merino wool/13% nylon | Not Available | $115 |
| REI Co-op Midweight Long-Sleeve Shirt | Silk | Not Available | $54.95 |
| REI Co-op Merino Midweight Bases Layer Half-Zip Top | Merino wool | Not Available | $59.95 |
| Icebreaker 260 TechHalf-Zip Base Layer Top | merino wool | 35 | $135 |
| Odlo Men’s Active Warm Eco Baselayer Top with Face Mask | 50% wool/37% polyester/11% polyamide/2% elastane | Not Available | $115 |
| Smartwool Merino Sport Hoodie | Merino wool | Not Available | $97.73 |
| Under Armour ColdGear Base Layer Bottoms | 82% polyester/18% elastane | Not Available | $60 |
| Patagonia Capilene Midweight Base Layer Bottoms | Polyester | Not Available | $69 |
How to Choose the Best Base Layers – Buyers Guide 2025
Base Layer Materials
Photo: Chris Lininger
There are a variety of different materials available when it comes to base layers. The most common are synthetic fabrics – like
polyester and nylon – and natural materials like Merino wool and silk.
Certain fabrics are better at some things than others. The main characteristics you want to look for when shopping for the right base layer for you are moisture-wicking, quick-drying, breathability, and odor resistance.
Let’s take a look at each fabric and see how they fare.
Synthetics:
In the synthetic fabric category, it’s most common to see base layers made of polyester and nylon. There is also rayon, polypropylene, and blends. Synthetics’ greatest strengths are their quick-drying and wicking properties that give you the driest feeling of all the material options. They’re also the winner in the durability category.
On the flip side, nylon and polyester’s weakness is odor resistance. Some synthetic garments are treated with an antimicrobial finish to limit the growth of odor-causing bacteria, but otherwise, they require frequent washing to eliminate the stink.
Merino Wool:
The strength of Merino wool is that it’s very soft and non-itchy against the skin. It offers excellent moisture wicking and warmth, yet also provides cooling in warm weather. The big plus about wool is that it’s naturally resistant to the bacteria that cause odor, so you can go days without washing it and still feel fresh.
Merino wool’s weakness is in the cost. Long underwear made of pure Merino wool is usually quite expensive. It’s not as durable as a synthetic material, so you must find the value in its comfort, temperature regulation, and odor-resistance to make your investment worthwhile.
Silk:
Silk is a great all-natural alternative for less sweat-inducing activities. Silk’s greatest strength is how soft it feels as a second skin layer. It’s extremely lightweight, which makes it comfortable and easy to layer.
The weaknesses of silk are its moderate ability to wick away sweat and keep you dry. It’s also not odor resistant, so a silk base layer will require frequent, delicate washing.
Durability
Photo: Chris Lininger
When weighing out the pros and cons of each type of material, don’t forget to consider durability. When investing in a base layer, it’s good to manage your expectations of how long the garment will last.
Merino wool is exceptional in many areas, but one of its weaker points is durability. As an all-natural fabric, it will inevitably wear out with time and extensive use. Paying attention to proper care will certainly help, but it won’t last as long as synthetic material.
More durable materials include polyester and nylon. You won’t get the odor-resistance and warmth of wool with synthetic materials like polyester and nylon, but they will last the longest with the most amount of use.
Warmth
Depending on what conditions you need your base layers for, you’ll want to pick long underwear with the proper weight and
Photo: Chris Lininger
thickness. The numbers – i.e., 150, 200, 250 – are associated with this rating. Basically, the higher the number, the heavier and thicker the garment.
For hiking to the summit of Mount Kilimanjaro, a 150 won’t give you enough warmth. Whereas for moderately chilly autumn morning runs, a 250 would be overkill.
For hiking it hot conditions at lower elevations, my Smartwool Merino 150 Crew is my go-to. When I am camping above 4,000 meters and need something to keep me insulated from the morning/evening cold – it is a 250 layer all the way.
Insulation and Weight
Which underwear weight you need will depend mostly on your typical level of activity, the conditions you’ll be in, and your metabolism. If you tend to run cold, a heavier weight will work better for you.
There are three main weight options for base layers:
- Lightweight: best for warm to cool moderate temperatures
- Midweight: best for cold temperatures
- Heavyweight: best for below-freezing temperatures
Crew Neck vs. Quarter or Half Zips and Fit
Typically, you’ll find most base layer options in crew neck style, as they’re meant to serve as your next-to-skin layer with other layers added on top. But a quarter or half-zip style base top may be a favorable option for you if you intend to use it on its own – or if you tend to heat up quickly during intense activity and need a quick cool-down method.
Speaking of next-to-skin, a snug fit next to your skin is also super important. The main purpose of a base layer is to wick away moisture and keep you dry, which the top can’t do as efficiently with a loose fit. Make sure that the base layer top you choose feels like a comfortable second skin in order for it to do its job.
Layering Systems: Base, Mid, and Outer Layers
Photo: Chris Lininger
In order to do layering properly, first, you need to understand the layering system and know what the function of each layer is.
- Base layer: this is your underwear layer that’s meant for wicking sweat off your skin
- Middle layer: this is the insulating layer that’s meant to trap your body’s heat to keep you warm in cold conditions
- Outer layer: this is your shell layer that’s meant for rain and wind protection
Every layer serves it own purpose – so if you skimp on one layer – the whole concept of successfully insulating yourself from the elements can go out of the window. The art of layering is very important skill to master, but it is not rocket science. Invest in quality layers and you will continue to enjoy harsh-weather environments. It is that simple.
Looking for an awesome outer layer, check out the best winter jackets on the market.
How We Tested The Best Base Layers
When it comes to testing out travel and adventure gear, here at TBB we’ve got plenty of experience from various trips and experiences around the world. So we feel justified when we say we, we got this! So what does that exactly mean when it comes to testing gear?
Well, we used the following metrics to assess every bit of gear to put together our ultimate guide: Firstly we look at how well made each base layer was, how durable and also how long-lasting they are. We also looked at things like how much each one weighs and how packable it is. Most importantly we looked at how comfortable each base layer is as well as how warm and dry they kept us.
Finally, we also take into account how an item is priced. We gave the cheaper options a few more passes when it came to flaws and judged the expensive gear a little more harshly.
FAQ about the Best Base Layers
Still have some questions? No problem! We’ve listed and answered the most commonly asked questions below. Here’s what people usually want to know:
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Final Thoughts
Layering is a tried and true art that has stood the test of time – and that’s because it works! Top performance in cold weather that can reach sub-zero temps requires having the right layers and knowing how to use them – the first being your base layer.
As you’ve seen, there are lots of options when it comes to finding the best base layer, and there are probably more things to consider than you thought. I hope my top picks have helped you narrow down your list and provided good pointers.
If in any doubt, go with my favorite base layer: the Icebreaker 200 Oasis Crew Top. I have been rocking this one for years and it is still going strong (just a little sun faded now!).
Stay warm and dry, my friends!
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You can now buy The Broke Backpacker a coffee. If you like and use our content to plan your trips, it’s a much appreciated way to show appreciation 🙂
