Best Thermal Underwear Styles for Men and Women

best thermal underwear

In our search to find the best thermal underwear styles, we purchased from the top brands and tested them out ourselves. One way to find out the quality of a company’s product is to test it out in the middle of a European winter. To find out if the top brands on the market and best thermal underwear styles live up to the hype, there’s nothing quite like a field test. The stakes are high. If you make a poor purchase, you’ll feel the icy cold winds (and possibly snow) through your clothes on your trip. By making the right purchase you’ll be cozy and comfortable for all your days of adventure and fun. Luckily, we have taken the guesswork out of it for you. All you have to do is kick your feet up and read along.

Different Materials of the Best Thermal Underwear (and how warm they are)

Whether you’re hitting the slopes for ski season or somewhere cold for New Year’s Eve, you’re going to want the best thermal underwear. Our picks on this list are made from durable materials, offer moisture-wicking properties, and thermal insulation from the elements. More often than not, these thermals are made from merino wool or a combination of cotton and polyester. Personally, we appreciate thermals with a bit of stretch to them. This makes them fit more comfortably underneath your mid-layer.

Why You Need the Best Thermal Underwear for Your Travels

If you’re traveling in the summer season, you won’t need thermals. Generally speaking, investing in the best thermal underwear is primarily for a winter trip. However, some areas still have chilly weather in the fall or spring. It’s better to come prepared than be cold on your trip. If you’ve ever been on a cold weather trip, you know that it takes a bit of extra planning and thought.

Common Features of the Best Thermal Underwear

  • Moisture-wicking properties
  • Thermal insulation
  • Tagless labeling
  • Fits loose on the body, allowing for a complete range of motion
  • Stretchy fabric
  • Perfect for layering on its own
  • Made from merino wool or a polyester and cotton combination
  • Neutral colors (black, white, gray, and tan)

How to Choose the Best Thermal Underwear for Your Next Winter Getaway

Before you purchase your thermals, make sure you take a good look at the size chart and match up your measurements. Generally, you can get a good sense of what size you would be by reading the height and weight charts. Nothing is worse than walking down the street wearing thermals that are too baggy and slipping down around your waist or are too small and ride up. Taking the type of material you would like into account is important too. Some travelers prefer wool whereas others prefer the polyester and cotton fabric blend.

Here Are Our Picks for the Best Thermal Underwear for Men and Women

In this article, we’ll show you the best thermal underwear picks in styles for both men and women. These minimal styles and high-quality design go a long way. First, we will take a look at the best thermal underwear tops and bottoms for men. Then, we will move along to the women’s featured products. Are you ready? Let’s go.

Best Thermal Underwear Styles for Men: Tops

SmartWool Men's Merino 150 Baselayer Long Sleeve

best thermal underwear - SmartWool

This is an all-around fantastic base layer. Not only does it stay in place but it also wicks moisture away from your body while you’re working and keeps you warm while you’re taking a break. What really set this SmartWool style apart in our book is the comfort and fit. The sizing chart accommodates all types of body shapes and heights. Even the tallest users applaud its fit and stretchy fabric. Overall, it fits very well and doesn’t cling to your shoulders and back too much.

The microfiber fabric is composed of merino wool yarn spun around a nylon base. This made it particularly soft in comparison to other styles. Despite having the lightest fabric of the styles we tested, its insulation properties are amazing. Since the shirt is so thin, it is very breathable. Did we mention that it also offers UPF 30 protection? It will keep you toasty in cold, snowy, and wet weather. On warmer days, it also works as a base layer for sun protection. The SmartWool Men's Merino 150 Baselayer Long Sleeve is such a smart buy.

Tech Specs:

  • Material: 87% merino wool and 13% nylon core
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    Moisture-wicking properties 
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    UPF 30 protection 
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    Accommodates a variety of heights and body shapes 
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    Stretchy fabric 
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    Breathable 
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    Works as a base layer for sun protection on warmer days

Pros

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    Moisture-wicking properties
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    UPF 30 protection
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    Stretchy fabric
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    Breathable

Cons

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    None

Best Thermal Underwear Styles for Men: Bottoms

Carhartt Men's Base Force Wicking Cotton Super-Cold Weather Legging

best thermal underwear - Carhartt

This style from Carhartt is created for men on the go and made to last. Composed of 100% cotton, it will keep you warm and help to get rid of sweat. Reinforced stitching and sturdy cuffs help to seal in body heat no matter what activity you may be doing. In this underwear, you will be prepared to take on even the harshest cold without worries. Stain breaking technology helps to release stains when you throw them in the wash. 

Tech Specs:

  • 100% cotton material
  • Reinforced stitching at points prone to wear and tear 
  • Sturdy cuffs 
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    Stain breaking technology 
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    Heat retention 
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    Moisture wicking 

Pros

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    Reinforced stitching
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    Stain breaking tech
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    Sturdy cuffs
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    Heat retaining and moisture wicking

Cons

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    100% cotton material is prone to shrinking

Duofold Men's Midweight Double-Layer Thermal Pant

best thermal underwear - Duofold

Are you looking for the best thermal underwear styles for extreme cold? Consider the Duofold Men's Midweight Double-Layer Thermal Pant. The exterior layer of nylon and cotton material is super soft to the touch. The interior material is made from 65% cotton, 25% merino wool, managing to retain your natural body heat. Besides the material, flatlock seams make them invisible under your clothing and you won’t have to deal with annoying chafing. To avoid any annoying itches, the elastic band is tag-free.

Tech Specs: 

  • Exterior material: cotton and nylon
  • Interior material: cotton, merino wool 
  • Flatlock seams for invisibility under your clothes 
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    No annoying chafing 
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    Tag-free elastic waistband 
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    Retains your natural body heat 

Pros

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    Nylon and cotton blend out materual 
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    Soft, moisture-wicking inner fabric
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    Flatlock seams
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    Tag-free elastic waistband
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    Thermal insulation

Cons

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    None

First Lite Allegheny Full Length Bottom

best thermal underwear - First Lite Allegheny

It’s easy to see that the First Lite Allegheny Full Length Bottom was designed with adventurers in mind. Easily one of the best thermal underwear styles, it will keep you warm and cozy in the great outdoors. Since the material is composed of 100% merino wool, you can rest easy knowing that it is effective to keep you warm, reduce sweat, and fight off odor. In addition, there is minimal stitching in sensitive areas, so you won’t be exposed to chafing from fabric. The result is an all-day comfort you won’t ever want to take off.

Tech Specs:

  • 18.5 micron superfine 100% merino wool
  • Naturally antibacterial and prevents odor 
  • Thermal insulation 
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    Naturally fire resistant
  • Covered by the First Lite product warranty
  • Moisture-wicking properties 

Pros

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    Antibacterial
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    Thwermal insulation
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    Fire resistant
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    Moisture-wicking

Cons

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    None

Best Thermal Underwear Styles for Women: Tops

Cuddl Duds Women's Softwear with Stretch Long Sleeve Crew Neck Top

best thermal underwear - Cuddl Duds

This attractive base layer fits like an expensive athleticwear piece from Lululemon - except it comes at half the price. We can’t believe what a steal this style is. While we love the length and feel of the shirt, our favorite feature has to be the thumbholes. When we tested this shirt out during our travels, the super-soft velvety fabric kept it from riding up and made it super comfortable to wear.

If you’re looking for a good base layer for moderately cold weather, this is a good choice. However, it is important to note that it isn’t as warm as some of our other choices for the best thermal underwear. Here, comfort is key. So, if you want to prioritize that, the Cuddl Duds Women's Softwear may be right for you.

Tech Specs:

  • Material: 93% modal and 7% spandex
  • Can be machine washed 
  • Velvet-soft fabric 
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    Thumbholes 
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    Good base layer 
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    Body-hugging fit 
  • Hem hits at the low hip
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    Slim fit (no bulk)
  • Lightweight comfort and bulk 

Pros

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    Stylish
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    Soft fabric
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    Lightweight and durable

Cons

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    Isn't a super warm style

Duofold Women's Heavyweight Double-Layer Thermal Shirt

best thermal underwear - Duofold

This double-layer heavyweight thermal is perfect for extreme temperatures. If you’re seeking something that can hold up well against the elements, this could be the best thermal underwear style for you. Made from 96% polyester and 4% spandex bi-ply, its moisture-wicking technology moves sweat away from your body and skin while locking in heat. Even better, it’s antimicrobial for odor resistance.

Tech Specs:

  • Double-layer
  • Thermal heavyweight 
  • Material: 96% polyester and 4% spandex bi-ply 
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    Moisture-wicking properties 
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    Thermal heat insulation 
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    Tag-free
  • Stretchy
  • Flatlock seams
  • Perfect for athletic activities
  • Antimicrobial for odor resistance 

Pros

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    Great material
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    Flatlock seams
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    Tag-free
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    Stretchy

Cons

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    Runs on the small side

Terramar Women's Thermasilk Scoop-Neck Top

best thermal underwear - Terramar

Luxurious, comfortable, and soft this is just the base layer you need. The Terramar Women's Thermasilk Scoop-Neck Top maximizes insulation and moisture regulation. The shirt is made from all-natural 100% pure silk. That means it’s lightweight, there’s no bulk, and no fuss. What could be more soft to the touch? Even though it’s incredibly light, it’s also so strong. Enjoy a natural stretch for all-day comfort.

Tech Specs:

  • 100% pure silk
  • Lightweight body 
  • Great insulation 
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    Soft to the touch 
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    Strong fabric and high-quality design 
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    Hand wash or machine wash on delicate 

Pros

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    Lightweight and comfortable fit
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    Moisture-wicking
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    Great insulation
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    High-quality

Cons

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    Hand wash or machine delicate cycle only

Best Thermal Underwear Styles for Women: Bottoms

Terramar Women's Thermasilk Pant

best thermal underwear - Terramar

If this isn’t the ideal base layer, we don’t know what is. Soft and well-sewn, it is lightweight yet surprisingly strong. Thermoregulation technology helps you to retain a decent temperature and dry quickly. It’s not only designed for an attractive aesthetic. The pants feature an elastic waistband, rib cuffs with spandex, and an attractively-shaped pattern with all-day comfort.

Tech Specs:

  • 100% pure silk
  • Soft and well-sewn 
  • Lightweight and strong 
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    Thermoregulation technology 
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    Retains heat well 
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    Quick-drying 
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    Elastic waistband 
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    All-day comfort
  • Rib cuffs with spandex 

Pros

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    Lightweight and durable
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    100% pure sulk
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    Thermoregulation tech

Cons

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    Waist isn't very stretchy

Common Questions