For centuries, people have raised Merino sheep for their wool. Merino wool is known for its softness, making it ideal for underwear and base layers. But Merino wool is much more than that, says Rita Kulis Samuelson, vice president of the American Wool Council in Colorado, who calls it a “miracle fiber.”
“Merino wool feels great against the skin because the fibers are so fine,” she said. “When you choose merino wool clothing, you know it’s biodegradable, reusable, flame-retardant, waterproof and eco-friendly.”
This fabric is also known for its moisture-wicking properties, which prevents the growth of odor-causing bacteria. As a result, merino wool stays fresher longer and helps prevent sweat and odor.
Today, travelers can find a wide range of merino wool clothing, from underwear to sweatshirts. As seasoned travelers, we’ve worn our fair share of merino wool underwear. Here are a few of our favorites.
Merino wool has natural temperature-regulating properties, is moisture-wicking, and is odor-resistant, making it ideal for underwear. Since you’ll likely be wearing other clothing over your bra, it should feel soft and comfortable (not too tight, not too loose). Our recommended merino wool base layers are made from 100% merino wool or blended with other fabrics. Keep reading to learn more about each bra, plus our buying tips.
Why we like it: This base layer from Smartwool is perfect for year-round adventures. These legging-inspired styles feature a wide elastic waistband and improved seam finishes for more stretch than previous styles. The average size for men and women has an inseam length of 31 inches, which is enough to cover the ankles of a 5-foot-7-inch person. Taller people can wear this base layer as cropped leggings.
Overall, this is a lightweight and versatile piece that can be worn with joggers, jeans, or hiking pants. The fabric is mostly merino wool, which feels soft like a sweater and is comfortable to wear every day.
Please note: This base layer is made from recycled nylon, which is not ideal if you are environmentally conscious. The pants are slightly stretchy, which may cause some sections to be see-through. This base layer is suitable for most cold climates, but is not suitable for use in sub-zero temperatures.
Product details: Sizes: Women’s: XS-3XL; Men’s: S–XXL | Composition: 88% merino wool, 12% nylon
Why you should buy it: Swiss sportswear company Mammut makes gear, accessories, and apparel for skiing, mountaineering, and hiking. The merino wool baselayers are part of the company’s “Trift” collection, which the company says helps travelers stay warm and active in the coldest climates without sacrificing functionality, range of motion, or comfort.
This top is form-fitting and has longer sleeves to better cover your arms. The high collar helps keep you warm, and the front zipper allows you to cool down and breathe. The fabric contains 8% spandex, which is stretchy enough for skiing, snowboarding, or any other intense activity. The front and back of the leggings (at the knees) are also stretchy.
Please note: The fabric is a polyamide blend, which the company claims provides durability and dryness, but this may impact the material’s odor resistance and breathability.
Why we like it: Crafted from premium merino wool fibers, this casual top is perfect for everyday wear. We love the softness of this shirt, but its real selling point is the design. Functional details like thumbholes, elastic seams, and a half-zip make the jacket versatile, making it easy to wear for both casual winter hiking and more active pursuits like skiing and snowboarding.
NOTE: If you are over 5’10″, the thumbhole may be shorter. The upper only comes in two colors: eggplant and vintage pattern.
Why we like it: These midweight pants combine premium nylon with the natural properties of merino wool. The fabric also has a degree of stretch, which allows for a comfortable fit, easy layering, and maximum warmth.
The slim elastic waistband provides comfort, while ergonomic panels enhance freedom of movement. The inseam length of the large size is 32 inches, and for tall people, it covers the leg below the ankle. We also really appreciate the fact that the merino wool is ethically sourced.
Please note: This base layer is treated with silver nitrate to improve odor resistance. Silver nitrate is a compound that enhances UV protection and prevents bacterial growth. Exposure to silver nitrate does not pose any particular health risks to humans, but silver-treated clothing may end up in waterways when washed.
Recommended Reason: Merino wool is moisture-wicking, odor-resistant, and non-stick, making it a great sock material. Ideal for year-round hiking.
These mid-calf socks feature a cushioned footbed and lightweight arch support for a comfortable fit. The stretchy fabric and cable knit pattern will keep your socks fresh and free of bunching in your shoes. The company is also offering 50% off four-packs of a variety of styles, colors, and patterns.
Please note: These socks contain a small amount of polyester and spandex and are therefore not fully biodegradable. We noticed that the socks pilled slightly after the first wash.
Why we like it: This crewneck sweatshirt is a great layering piece for all seasons. The silhouette is slightly fitted so you can move freely. The sleeves are set-in for ease of movement, and the side slits at the hem provide enhanced ventilation.
Additionally, the shirt is made from a blend of merino wool and polyester, which improves the performance characteristics of the product – it wicks away moisture and dries quickly. Many Patagonia shirts, including this one, have a loop on the back of the collar for easy hanging.
Please note: A slightly longer back edge on women may not suit everyone.
Why we like it: Icebreaker uses the finest merino wool fibers to make this swimsuit, which makes it super lightweight and soft. The fit is sleek and form-fitting, with a low-to-mid rise and medium coverage in the back. The fabric has a degree of stretch to help it hug the body, and the waistband keeps the bikini in place. We love that this style comes in both classic and unconventional colors like sage and orange.
Please note: Some customers feel that this bikini style is too tight and does not provide enough back coverage. This bikini is available in plus size.
Why we like it: The Unbound Merino boxer briefs are pretty classic, with a 5.5-inch inseam in all sizes and an elastic waistband with no tag. Nylon helps wick moisture and dry quickly, while spandex provides a comfortable fit without restricting movement. These boxer briefs are also machine washable.
Please note: These boxers have a comfortable mid-rise, but some may find the waistband too tight.
Why we recommend it: This super-soft merino wool bra is a great choice for everyday errands, walking, or light physical activity. It’s wire-free, making it easy to put on and take off, and the straps cross at the back so you can wear it over a racerback. The deep V-neck at the front means you can pair it with almost any outfit without worrying about it showing.
Please note: This bra is unlined and has no pockets for padding. They are similar in style to sports bras but provide less support. Best suited for C cups or smaller.
Why we recommend: Bionic This Italian-made base layer provides breathability and temperature regulation in cold weather. The company’s proprietary technology uses high-density knit fabrics that help maximize heat retention (they act as a filler but don’t add bulk) while keeping your body cool and dry.
The blended fabric has a medium compression level, which provides support without restricting movement or creating a feeling of tightness, even when worn under standard winter trousers.
Please note: Some people may find the compression a little uncomfortable at first. If you are looking for a warm, sweatshirt-like layer for everyday wear, this may not be the option for you. However, we think it is ideal for winter sports.
Product details: Sizes: Women’s XS-XL, Men’s S-XXL | Composition: 87% merino wool, 12% polypropylene, 1% elastane
Why we like them: These sweatpants are so comfortable, you could sleep in them. They’re made from heavyweight merino wool spun from microfibers that feel super soft and have just the right amount of structure and thickness. The tapered silhouette hugs the body but is loose enough to allow for movement. The elastic waistband won’t dig into your skin like some leggings can. We love that there are three pockets, plus a hidden zippered pocket on the right side for storing small valuables.
Why we like it: Quince is known for producing high-quality, affordable, classic essentials. This long-sleeve top is no exception. The crew neck makes it versatile—you can layer it underneath other layers while still enjoying all the benefits of pure merino wool on its own. We also love the feel of the knit and how comfortable it is to wear.
NOTE: This top is made from 100% merino wool and has little to no stretch. We recommend sizing up for a looser fit.
Why we like it: Regular bras aren’t usually great for wearing on their own; some bras are even sheer. These leggings combine the comfort of soft merino wool base layers with the thickness of leggings. They feature a high waist, a wide, adjustable waistband, and a patch pocket deep enough to hold credit cards and a regular-sized smartphone.
We love that they’re not too tight, so they’re just as comfortable for traveling or doing active wear, and they still look great layered with a shirtdress or skirt.
Note: These leggings are cropped, so you might want to wear a liner or socks to cover your ankles. I also wish they had a second side pocket.
Why we like it: This classic beanie with a rounded brim is a must-have for winter sports. The two-layer fabric construction helps keep you warm, and it can be easily worn under a jacket hood, even in cold weather. We also really appreciate that it comes in more than 10 colors and patterns.
Please note: This hat comes in one size and fits best on head circumferences between 21.5 and 23.5 inches.
While merino wool clothing remains high-quality year-round, its quality can vary depending on factors such as fiber thickness, fabric weight and construction, material combinations, silhouette, and style. Here is our curated list of the best merino wool clothing and accessories.
• Third-Party Reviews: We reviewed dozens of customer reviews from retail and editorial sites for every product on our list. We also consult with other travelers and outdoor experts to ensure consistency of experience and quality.
• Fiber diameter: Whenever possible, we pay special attention to technical characteristics such as fiber thickness. But we are especially interested in the fiber diameter, as it affects the softness of the product.
• Fabric weight: Merino wool comes in different weights: light, medium, and heavy. These values ​​depend on the thickness of the fabric and indicate the seasons, temperatures, and activities that each item is best suited for.
• Fabric composition: We pay attention to the composition of each product, as merino wool is often blended with other materials to improve performance and durability. Fabric composition can also affect the biodegradability of a product.
• Fit: Comfort depends largely on the fit and cut of the garment. Undergarments (both tops and bottoms) are usually designed to fit closer to the skin.
• Brand Reputation: We consider a company’s history, renowned manufacturing practices, and reputation among outdoor enthusiasts to determine product quality and durability.
Merino wool weight is measured in grams per square meter (g/m2). Some companies list the weight of the fabric in the product description so that consumers know what climate conditions the product is best suited for.