Best Underwear for Hiking: Smartwool, SAXX, PAKA, Icebreaker, and BN3TH Compared

Underwear for Hiking

With all the backpacks, rain jackets, specialty shoes and loads of other gear for outdoor adventures, it is easy to overlook one of the more important but least thought about aspects of your kit, the underwear. In the winter there are well developed base layers that protect you from the elements but in the summers what’s underneath is often an afterthought. So just what underwear is the best underwear for hiking?

There are some basic rules that you want to consider. First, are they comfortable? If you reach into a drawer and grab a pair that feels tight while you are sitting at your desk all week, it’s probably not the best option for the trail. Second, I usually avoid cotton if I can. Cotton tends to absorb moisture and become uncomfortable if you get caught in a rain storm or just sweat a lot. Finally, is the underwear practical. The same underwear that you wore out to the clubs on Friday night might not be the best underwear for the woods on Saturday morning. Function wins out over style when it comes to what lies beneath.

I was able to test a few different styles of underwear from different brands and wanted to share my opinions. I will say that, as a man, I only tested men’s underwear. Also, as a quick disclaimer, I was sent all of these for the purpose of testing. Plus, this site does use affiliate marketing links. If you use the buttons below and make a purchase, I may receive a small commission at no extra charge to you. Now let’s talk underwear!

Smartwool

Model: Men’s Merino Boxer Brief

Cost: $48.00

Material: 88% Merino Wool 12% Nylon

Pro’s

The Smartwool Men’s Merino Boxer Brief is a really nice and comfortable pair of underwear. The Merino wool is extremely soft. I could barely feel the underwear because it was so soft. It also is a good size and provides a lot of coverage. The material around the thighs stayed exactly where it was supposed to be and didn’t creep up my legs at all.

I was also really impressed with the moisture wicking abilities of the Merino Wool. I sweat quite a bit while hiking and always felt comfortable and dry. The temperature regulation was also really nice with the Smartwool boxers. I never felt overheated or uncomfortable on my hike.

Smartwool also uses the highest percentage of Merino Wool in this group. Merino has the natural abilities to regulate temp and moisture wick. Merino also has anti-microbial and anti-odor properties. I can’t tell about the microbes but I can agree on the anti-odor. This was a really nice pair of underwear.

Con’s

The only thing that I could find that I didn’t like on the Smartwool is the large waist band. The band is an inch and half wide which is a little bigger than others but not too bad. The concern is how thick it is. It feels to be about 2 to 2.5 times thicker than the rest of the underwear and I felt that it had a tendency to roll a bit around my waistline especially if I was hiking inclines where I bent in different directions to clear a rock or boulder.

Saxx

Model: Multi Sport Mesh

Cost: $27.00

Material: 89% Moisture Wicking Polyester, 11% Elastane

Pro’s

The SAXX Mult Sport Mesh underwear is a breathable mesh option. If you have never tried SAXX before, they have a pouch to kind of protect and separate your parts. Almost like a soft jockstrap. This was actually way more comfortable than I thought it was going to be. The polyester does a really good job of moisture wicking and it was a comfortable hike. I also found the mesh to be very breathable and allowed me to stay cool.

During the hike the legs of the SAXX Boxers didn’t ride up and everything was in place. They are also really lightweight and I barely even noticed I was wearing them. The waist band provided good support and didn’t slide up or down no matter how active I got on the trail.

Con’s

While SAXX has a protective pouch for the specific areas that need support, I found that this allowed for more friction with my thighs leading to some rubbing. It also takes a little bit to get used to the different feel of the pouch if you haven’t tried it before. These are mostly polyester and some people have allergies to that material.

PAKA

Model: Essentials Mens Brief

Cost: $38.00

Materials: 48% Tencel, 33% Organic Cotton, 14% Royal Alpaca, 5% Spandex in Waistband

Pro’s

The PAKA Essentials Mens Brief was extremely comfortable. This pair had the most material and was the biggest of the group that I tested. They fit a bit more like classic boxers where they weren’t overly tight through the legs and allowed really nice movement. I was also really impressed with how soft they felt. They use Tencel and Alpaca which are two of my favorite materials and always feel really comfortable against my skin. I’m not sure what material was used for what portions but the softness was universal. There was also a lot of flexibility and freedom of movement. Overall, these were a really nice pair of underwear.

Con’s

The only thing I really noticed with the PAKA briefs was that I felt like a bit of moisture collected on the underwear. It was about 10 degrees warmer on the day I tested these then all the other pairs but I don’t know that I sweat that much more and felt like moisture just didn’t completely wick especially around the seams.

Icebreaker

Model: Men Anatomica Boxers

Cost: $45.00

Materials: 83% Merino Wool, 12% Nylon, 5% Elastane

Pro’s

The Icebreaker Anatomica Boxers had the most classic athletic fit in my opinion. They provide a lot of support where needed but also have a good range of movement as I stepped onto inclines or boulders. The material doesn’t go as far down the thigh as other brands, maybe 1/4 down, but also I didn’t have any problem with them drifting up or rolling at the bottom. The waistband is also smaller so it doesn’t run as big of a risk of rolling during movements.

This is the second highest amount of Merino Wool of the group I tested and they performed really well. Moisture wicking was superb and the boxers felt breathable as well. Temperature wise, I felt comfortable and never felt overheated. Also, the Merino is anti-microbial and anti-odor and I can say that the anti odor worked. No microscope to check the microbes though. These were really soft as well and enjoyable.

Con’s

The Icebreaker Boxers were cut a little bit smaller than the rest of the brands. While the others were typically between 16 1/2 to 17 1/2 inches across at the widest point, the Icebreakers were only 16 inches. I ordered the same size for all of them so I believe it is just a different cut. This led to a bit of a tighter fit as you would imagine.

BN3TH

Model: Infinite XT2 Boxer Brief

Cost: $38.00

Material: 62% Polyester, 26% Tencel Modal, 7.5% Ionic Polyester, 4.5% Spandex,

Pro’s

Bn3th Infinite Boxer Brief is another entry in the pouch category. The protective pouch does a really good job and holds everything exactly where it should be. The Bn3th also have a really athletic feel to me. The legs go further down my thighs and are almost 3/4 of the way to my knee. The leg portions also do a really good job of staying exactly where they belong. They didn’t shift the entire hike which I was impressed with because of how long they were.

I felt comfortable in this underwear and thought it did a good job of moisture wicking and avoiding getting bogged down. The movement was really nice and I felt that I had a full range of motion. As far as temperature regulation goes, I didn’t notice, which means that it didn’t retain heat and I didn’t overheat. They weren’t as soft as some of the Merino and Alpaca pairs but I think these might have been the most athletic feeling of all the pairs in their design and function.

Con’s

I found that where the pouch comes together can cause a bit of rubbing in the area at the bottom of the pouch. The area where everything kind of connects below. That was all I really had for the Bn3th.

Final Thoughts on Underwear for Hiking

All of these underwear work well for hiking. I have worn them all and found a lot good and maybe a thing here or there that wasn’t perfect. The pouches or SAXX and BN3TH are new for me but I kind of like them. The merino wool of Icebreaker and Smartwool are both really nice. Definitely, not your grandparents itchy wool, instead a smooth moisture wicking material. I enjoyed the super soft comfort of PAKA’s alpaca option.

I can’t, or won’t, pick a winner other than to say you wouldn’t go wrong with any of these options. It seems like a little thing but the first time that you have a bad pair of underwear on a long, hot hike you will wish you had a pair like this to make it a little more comfortable and a little less chafing. It is nice to have one less thing to worry about on the trail and with any of these, you won’t worry again.

More from the Fatman

For a list of other products that I have reviewed you can check my Product Review page here. If you have any products you would like me to review or any comments you can email me at fatmanlittletrails@gmail.com or you can follow me on any of the below social media platforms. Happy Hiking!