Best Thermal Underwear For Hunting – Tell All Buyer’s Guide

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Sometimes it can get really chilly when you’re out hunting in the early morning or winter months. What better way to keep yourself insulated than to wear a pair of thermal underwear. This underwear is designed to keep you insulated.

However, there are certain features of the underwear that will maximize the effectiveness of the heat retention.

This article will discuss the various products on the market and their benefits and disadvantages. We’ll also mention what exactly makes a great pair of thermal underwear.

Comparison of the Best Thermal Underwear For Hunting


Men Thermal Performance Underwear by Outland

  • Full body set
  • Stretchy material
  • Thin regulatory layer
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Thermajohn Thermal Underwear

  • Odor resistant
  • Ultra-soft polyester
  • Two piece thermals
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Duofold Men's Mid Weight Suit

  • 100% Cotton
  • Two layer thermal
  • Long-sleeved one piece
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Carhartt Men's Legging

  • 100% cotton
  • Thick elastic qualities
  • Can be machine washed
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Minus33 Merino Wool

  • Machine washable
  • 100% Merino wool
  • Wool is some of the softest material on offer
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What is Thermal Underwear?

You lose body heat mainly from evaporative cooling which is when your sweat will cool you down by drawing heat energy away from your body. The thermals will draw the sweat away from your skin which minimizes the evaporative cooling process. The best materials for this would be Wool, Wool-Bamboo blends and synthetic fabrics like an acrylic.

Why You Should Use Thermal Underwear While Hunting

There are many benefits to wearing thermal underwear while hunting, the following section will discuss this topic in more depth by mentioning the main benefits.

  • Keeps You Warm

One of the main benefits of using thermal underwear while hunting is that they keep you warm during the winter months or cold mornings. Being cold is a huge problem for hunters that like hunting animals that are active during the winter. It’ll also mean you won’t suffer from that bulky feeling from wearing too many layers if you’ve got one great solid layer.

  • Decreases the Chance of Illness

A big problem that these thermals solve is that if you sit in your own cold sweat for too long you’ll develop a cold or something more serious. By absorbing your sweat, these thermals greatly lower the chance of catching the common cold. Meaning you can live to hunt another day.

  • Comfortable

How many times have you worn a pair of underwear and then some heavy hunting pants over it and they’ve started to rub up the wrong way? Too many times. However, thermal underwear will be able to adjust and attach themselves to suit your body shape so that this problem will never happen again. You’ll be snug as a bug in these pants and you’ll never regret it.

How to Choose Thermal Underwear

Like all great products, there are different features that will allow each to stand out and come off as unique, ultimately giving them an advantage. The following section will discuss what features you should be looking out for that’ll make the underwear some of the best.

  • Material

The different material that’s used in certain thermal underwear will offer a variety of benefits and downsides. Mostly all thermal underwear is made from synthetic fibers such as spandex, polymer, nylon or polyester, these are great for cool environments.

However, natural fibers are a lot more effective at keeping you warm that these synthetic ones. The most widely used natural material is cotton as this is a great insulator and is really comfortable. Sometimes, natural is better.

Duofold Men's Mid Weight Suit - Inside Layer: 100% Cotton; Outer Layer: 65% Cotton, 25% Merino Wool, 10% Nylon Outer Layer

  • Layers

Another feature that is more important than the material is how many layers your thermal underwear has, the more layers the more resistant it is to cold weather. Some products might only have a few thin layers which are great for when you’re in cool temperatures.

However, thick and plenty of layers will allow you to hunt in the coldest of temperatures. This feature is more important than the material in terms of retaining body heat.

  • Breathability and Comfort

If you’re trying out your new thermal underwear, you want it to be as comfortable as possible. One way to see if it’s the right thermal for you is to understand how you feel in them. It shouldn’t make you feel hot or sweaty, you should feel warm and comfortable, if you’re sweating a lot, this means that the material can’t breathe because the thermal is too tight on your body. Ensure that the material doesn’t cause any itching or discomfort as this will cause you more hassle than it’s worth in the long-run.

Quick Take | Best Thermal Underwear For Hunting

Just looking for the top three best thermal underwear for hunting? Here they are:

  1. Men Thermal Performance Underwear by Outland
  2. Thermajohn Thermal Underwear
  3. Duofold Men's Mid Weight Suit

Review of the Best Thermal Underwear For Hunting

This is the most important section of our article as this is where we can discuss the various thermals on the market that we believe to be the best. We’ll talk about their features, pro’s and con’s and give you an honest opinion of each.

Men Thermal Performance Underwear Set by Outland; Base Layer; Soft Fleece; Warm Long Sleeve Shirt and Long Johns


  • Elastic
  • Full Body Set
  • Microfiber Fleece
  • Keeps You Warm in Cool Conditions


  • Not as Effective During Winter

This top and bottom thermal set is great for any hunter that is looking for full thermal protection rather than just underwear. Perfect for cool conditions, the polyester material provides you with a thin and lightweight layer that acts as a second skin because of its elastic quality which will allow you to be just as flexible as you were before.

The material successfully draws the moisture from your skin so that it insulates your body and keeps it dry. The full kit is easily washed and won’t shrink like many other products of this kind do. The microfiber fleece will effectively replicate that soft, natural cotton feeling against your skin.

Bottom Line

This product will be able to keep you warm during those cold mornings hunting, the early bird always catches the worm. However, the bird needs to be warm. The microfiber fleece is what provides that extra comfort which is a cloned feeling of soft cotton.

The polyester material will successfully act as a protective and insulative layer by drawing out the heat and absorbing any sweat. The only real downside to this product is that the hunter won’t be as warm during the freezing winter months because of the short, synthetic fibers.

Best for the Money:
Thermajohn Thermal Underwear

Thermajohn Men's Ultra Soft Thermal Underwear Long Johns Set with Fleece Lined


  • Flexible
  • Soft Polyester
  • No Bad Smell Stains
  • Argan Oil Makes it Soft


  • Not a Great Absorber

The fibers of this polyester two-piece are woven with argan oil which gives it the super soft feeling as if it were cotton. The material is also stretchable which means you’ll benefit from the same flexibility as you would without it on.

Acting as an effective barrier between you and the cold, the fibers will trap any body heat you produce which makes you feel as warm and comfortable as you need to be on those early cool mornings. If you find yourself sweating too much after a lot of walking you’ll be happy to know the material is also odor resistant.

Bottom Line

There are many benefits that come with this product, the main attraction being that the soft polyester is also finished with argan oil which gives it that extra soft feeling, perfect for sensitive skin. If you begin to sweat you’ll benefit from the anti-odor stain material, you could be walking for hours and still not smell a thing.

Another benefit of this two-piece would be the flexible material which allows for complete movement and no limitations. The only downside is that when you sweat it won’t be able to absorb it as well as natural fibers therefore you could start to get rather damp after a while of sweating, this would also mean you’d start to develop a cold sweat which could cause the cold or flu.

Thickest Thermal Underwear for Hunting:
Duofold Men's Mid Weight Suit

Duofold Men's Mid Weight Double-Layer Thermal Union Suit


  • Flexible
  • Cotton Material
  • One-Piece Dual Layer


  • Shrinks When Washed

The first cotton thermal product on the list, cotton is a great feature for any thermal product because it offers both great comfort and is a brilliant insulator. The two thermal layers is what will keep you warm during not only the cool mornings but the freezing winter months, this is something that no synthetic material would be able to properly accomplish.

The outer layers are also made partly from Cotton, Wool and Nylon. You’ll also be able to machine wash this product without sacrificing any of the beneficial natural materials. The stretchy one piece won’t limit your movement whatsoever and will continue to give you that flexibility that you need when hunting.

Bottom Line

The best material you could use when hunting in thermal underwear would have to be either Cotton or Wool, both materials offer some great warmth and can be really comfortable, thankfully this product is made from both. The one piece thermal is a dual layered product that will keep you insulated not only in the cool mornings but the freezing cold winter months, something that is rarely replicated by synthetic materials.

You’ll also benefit from a full range of movement because of the flexible and stretchy abilities. The only downside with such a product would be that it shrinks a little when you machine wash it. However, it should stretch back into shape once you wear it again.

Most Durable Thermal Underwear for Hunting:
Carhartt Men's Legging

Carhartt Men's Base Force Cotton Super-Cold Weather Bottom


  • Warm and Soft
  • Super-Thick Elastic
  • Machine Washable


  • Top Half Isn’t Provided

Hunting during winter can be painful when you think your legs are going to fall off from the cold. What better way to fix that than with a pair of extremely durable and thick thermal leggings.

This pair is made from 100% cotton which is well-known for retaining your body heat to provide you with a comfortable and warm feeling when hunting. One of the downsides of most cotton is that it can’t be machine washed, unlike this product which will easily stretch back once worn after being washed, thanks to the elastic features.

Bottom Line

These comfortable and warm leggings will help you survive the horrible, freezing winters by insulating your legs and absorbing the sweat which helps regulate your temperature more effectively. The machine washable leggings will shrink when washed but will spread back out once they’ve been worn again.

The super-thick elastic will also ensure that you’ve got complete control over your movement and you won’t be limited in any way. The only downside is that the top half isn’t provided with the purchase unlike every other set that’s featured on the list.

Editor's Pick:
Minus33 Merino Wool

Minus33 Merino Wool 706 Kancamagus Men’s Midweight Bottom - Anti Odor No Itch Renewable Fabric


  • 100% Wool
  • Super-Stretchy
  • Machine Washable
  • Perfect Range of Movement
  • Can be Used During Spring, Winter or Autumn


  • No Top Half Included

One of the two most widely used natural materials are either cotton or wool, the latter being the softest and probably the most comfortable. So, you’ll be happy to know that this is 100% Merino wool. The special, easy-care technology means that the fibers are machine washable and this won’t negatively affect the material itself.

The fibers are also able stretch and provide you with perfect range of movement and there is a guarantee that you won’t ever be limited in your movement because of these super-fibers. These leggings can also be used during the coolest temperatures of the year, like Spring, Winter and Autumn.

Bottom Line

There are many benefits that come with these thermal leggings, the main attraction being that you can use them throughout the majority of the year excluding summer of course. They’re also machine washable which is helpful as the effectiveness won’t be sacrificed.

The super-stretchy material will ensure that you’ve got a full range of movement which is really crucial for when you’re hunting. The only downside with this product is that there’s no top half that’s included with the leggings like mostly every other product on this list.


Thermal underwear are an important part of a hunters clothing kit, they keep you warm and comfortable and safe from the cold. However, these benefits can only be experienced if you’ve chosen the right features or qualities which we’ve kindly provided above. If you follow this guide, you’ll be sure to find the best pair on the market.

People Also Ask

This section is just as important, as this is where we have answered all of the main questions that we get asked, we hope that any questions you have will be answered in the following section.

What Does Thermal Underwear Do?

Thermal underwear will be able to keep you warm during the cool weather, depending on how many layers and the material used it’ll keep you warm even in the coldest months of the year. It’s also a more comfortable alternative to using normal underwear.

What is the Best Thermal Underwear Material?

The best thermal underwear material would probably be natural cotton, it insulates you the best and is also really comfortable. The reason why it’s better at insulating is because the fibers are longer than that of synthetic fibers, therefore it traps the heat better.

Do You Wear Underwear Under Thermal Underwear?

No, you wouldn’t wear underwear underneath your thermal layer, this would do the opposite of what it’s designed to as you’d sweat more with the extra layer between you and the thermal, this would get really uncomfortable.