Why Merino Wool Underwear?
Soft, breathable and naturally temperature-regulating, merino wool underwear has earned a loyal following among hikers, runners, travelers and increasingly, everyday wearers. One of its standout qualities is its natural resistance to odor buildup, helping it stay fresher for longer than many traditional fabrics like cotton and polyester blends. That makes it especially well-suited for multi-day hiking and backpacking trips, long-haul flights, workouts and sweaty summer days when staying comfortable can be a challenge.
While merino wool comes with plenty of advantages, it does benefit from a gentler care routine since it’s a natural fiber. Many brands recommend washing on a delicate cycle or by hand, then line drying or laying flat to dry instead of tossing them in the dryer, which helps preserve the fabric’s softness and shape over time.
Below, we’ve rounded up eight merino wool underwear styles to shop now.
1. An Everyday Pick Made with 100% Merino Wool
Designed for everyday wear, this Merino.tech merino wool underwear is made from 100% superfine merino wool. The fit is snug, and a four-way stretch construction helps the fabric move naturally with the body. Shop five color options, including olive green, navy and oatmeal, in sizes S-XXL.
Promising review: “No junk stuck to your leg. Good in the heat and cold. Thermo regulating.” — Kawiloje
$27 at Merino.Tech / $27 at Amazon
2. A Bulk Buy Option for Everyday Comfort
If you’re already convinced your drawer could use more merino wool underwear, the Forvevo merino wool boxer briefs come in a six-pack, making them a value-focused option. Made from 100% merino wool, they’re designed to help reduce friction and support all-day, itch-free comfort. Each pair features a 3D pouch for added support, along with a mid-rise fit that sits comfortably throughout the day. The six-pack comes in seven color options, including dark grey, black and mixed-color sets, with sizes ranging from S-3XL.
Promising review: “Best underwear you can buy. Merino wool anything is 100% worth your money. This underwear feels great. You never get sweaty swamp butt like those other cotton underwear - breathability is unmatched. I’ve bought 3 sets of these underwear to replace all the other gnarly pairs in my drawer. Fit, durability and stretch support are all exceptional.” — James Schroeder
$60 at Amazon
3. An All-Around Performance Boxer Brief
Made from a lightweight blend of 56% merino wool and 44% polyester, this Smartwool active boxer brief boxed is designed with movement in mind. A double front panel adds extra support, while flatlock seams help reduce chafing for a smoother feel. This style features a next-to-skin fit and comes in five color options on Amazon for single-unit purchases, including black, grey and teal, and is available in sizes ranging from S-XXL.
Promising review: “I purchased these for my significant other in preparation for walking the Camino Portugués in September 2025. He liked the way they felt, and their lightweight nature meant they dried quickly after handwashing in sinks (just be sure to roll them in a towel to get out excess water). Because the material was not overly thick, they traveled wonderfully and did not add a ton of extra weight to our packs. Great value for the money, as they still look new. The material means they don’t reek and offend others, either. Win-win.” — Lauren1276
$40 at Amazon / $40 at Smartwool
4. An Affordable 2-Pack of Boxer Briefs from a Trusted Outdoor Brand
This well-priced 2-pack of boxer briefs from Columbia includes a duo of 50% merino wool undies equipped with a logo-ed waistband and a supportive pouch.
$25 at Amazon (regularly $60)
5. An Airy and Lightweight Boxer for Warm Days
A trusted name among outdoor enthusiasts, Icebreaker is best known for its well-made merino wool pieces, including base layers, midlayers and socks designed to keep you comfortable while spending time outside. These lightweight merino 125 Cool-Lite Anatomica boxers feature a mid-rise fit and are made with a stretchy and breathable Cool-Lite fabric to regulate temperature as conditions change throughout the day. On Amazon, they come in six color options, including black, heather gray and navy, and are available in sizes ranging from S-XXL.
Promising review: ”No mo smellycat. Holy crap, I love these. I'm a chick who sits in a wheelchair or a handcycle a lot and these take the funky out of my town!” — Jennifer
$50 at Amazon / $50 at Icebreaker
6. A Streamlined Brief for Everyday Performance
Designed for warm-weather days and higher activity levels, this Icebreaker Anatomica brief is a streamlined option for those who prefer a closer fit over boxer-style underwear. It’s made from a blend of 83% merino wool, 12% polyamide and 5% elastane, combining natural temperature regulation with added stretch for ease of movement throughout the day.
Promising review: “Just what Jed would say about these. I did not know about merino wool undies until I was in my 60's...40 bucks a pair has this old man poorer but happier. No more clammy damp nether region. God did put our junk on the outside so it could stay cool, but since Man exchanged Kilts for trousers we have paid the price. They last a long time after cotton undies have turned into a saggy stretched out mess and have to be discarded. I checked back on my previous purchases and had bought 18 pair of cotton undies in a similar time period I bought 3 of these - so not so expensive after all.” — David Graham
$40 at Amazon / $45 at Icebreaker
7. A No-Blend Option for Merino Purists
Made from 100% Australian merino wool in a lightweight knit, this Minus 33 lightweight boxer brief is designed to stay breathable in warm conditions while still providing light insulation when temperatures drop or activity levels increase. It features a close, body-hugging fit that stays in place during movement, whether you’re running, hiking or biking and is available in sizes XS through 4XL, with six color options including olive green, navy and tan.
Promising review: “These are the ones. They fit excellent, stay put, and protect you from chaffing. I forget I am wearing these unlike some other underwear.They never smell, I don’t wear them for a week without washing but you could. I sweat in them welding in overalls and cover alls in 114 degrees all day and they didn’t smell at all and dried super fast.Washing, when done with other Marino wool products, dos not seem to cause pilling or fraying. And they have not shrunk on me.The over all quality is great and this is the best pair of underwear I have ever had. Probably the only pair I’ll buy moving forward aside from their briefs which are also great but ride up your bum if you bend and perform larger movements. Get these instead.” — Ryan T.
$45 at Amazon
8. A Super Soft Option That Also Meets Sustainability Standards
This Woolly Clothing Co. merino boxer is made from 100% ultralight Australian merino wool and designed as an everyday option that feels light and soft, with a relaxed fit that drapes naturally rather than clinging to the body. The brand also highlights its sustainability standards, with RWS certification indicating that the wool is sourced from farms that meet the Responsible Wool Standard, a third-party certification focused on animal welfare and responsible land management in wool production. Plus, if you’re not satisfied within a year of purchase, the brand will replace your pair. Shop this style in six color options for single-unit purchases, including white, salmon pink and charcoal, in sizes S-XXL.
Promising review: “The Rolls Royce of Underwear... They are hands down the most comfortable underwear I have ever worn... They feel great on the skin and dont get hot or sticky... They are awesome at wicking away sweat and keeping you cool and dry.... Their customer service is top notch...” — Alan
$43 at Amazon
9. A Four-Season Staple from a Family-Owned Brand
This family-owned company is best known for its merino wool base layers used across hiking, snowsports and workwear, crafted with premium wool sourced from New Zealand farms. For an underwear option designed to handle a range of activities, including running, camping or just going outside for a walk, the lightweight Thermowave Merino Life merino wool underwear is a popular choice, and is made with 96% merino wool and 4% elastane. This style comes in four color options, including black, forest green and a grey-blue, and is available in sizes ranging from S-3XL.
$30 at Amazon
