This guide to merino wool clothes will walk you through how to shop and what details to consider, especially if you're seeking warmth for the outdoors!
This post is not sponsored by any of the merino wool brands listed below. We purchased and tested their products without brand collaboration.
If your hiking or camping trips have taken you through all the seasons and all sorts of weather, you know the importance of dressing for comfort.
And not just the kind of comfort that feels good when you first put something on. No — but the kind that lasts through cold, through perspiration, and through long hours.
If you've shopped around for the best base layers, one material that might keep popping up is merino wool.
Merino wool is often a great choice for outdoor recreation, and I've gathered a few tips that will make shopping for it much easier!
Here's a guide to merino wool clothes, along with some of our favorite products tried so far. Let's start with a few pros and cons.
Pros of Merino Wool Clothes
Merino wool is a natural fiber grown on Merino sheep. Whereas some people find traditional wool to be scratchy, merino is known for its soft texture.
It’s also great at wicking moisture from the body, which keeps you warm in the cold and cool in the heat.
It naturally resists odors and dries quickly. And it's said to be a sustainable, eco-friendly fabric.
Some brands (like Smartwool) advertise merino wool that's woven to include sun protection (UPF clothing.)
Cons of Merino Wool
The main drawback of merino wool is the price. It can be expensive!
Also, shopping for it can be a bit confusing, with terms like “gsm” (which we'll explain below).
Finally, merino wool is more delicate than synthetic fabrics, so it needs to be cared for more carefully.
GSM (grams per square meter)
The GSM numbers on merino clothes are a guide to how thick the wool is.
Not every brand includes the GSM number, but when it’s listed, it can be helpful to consider.
Numbers and descriptions between brands may vary, but here’s a general guide:
150 - 180: Lightweight fabric (summer weight), may be slightly see-through.
190 - 220: Midweight, mostly opaque. Great for layering.
230 - 320: Heavyweight, fully opaque, thicker fabric.
Wool vs. Wool Blend Clothing
Much of the merino wool clothing available, especially the merino wool clothing marketed to outdoor adventurers, is not 100% wool.
Instead, it’s often a blend of merino wool and synthetic fibers (such as polyester).
Merino wool is more delicate than synthetic fabrics. Adding synthetic fabrics to the blend can provide more durability. And that's what you want in sports clothing like leggings or bike shorts.
However, as the percentage of synthetic fabric goes higher, the less you’re getting the merino wool benefits.
It’s always a good idea to check the percentage of wool in a garment!
Sometimes the lower wool / higher synthetic blends are more affordable, but not always.
Some clothing items will even be totally synthetic on the outside with a partially wool lining, such as these Smartwool training shorts. You’ll usually see that on items that need lots of stretching ability.
Our Favorite Merino Wool Clothing
We tried lots (and lots) of merino wool clothing. After lots of testing, our absolute favorite brands are Branwyn, Icebreaker and Smartwool.
Clothing from these brands (in general) tends to be high-quality and hold up to wear and tear. In particular, these brands made clothes that held up to being used as activewear, which can be a little harder on clothes than casualwear.
Keep reading to see our full brand reviews below, plus our favorite items for each brand.
Not sure if you should choose between Icebreaker and Smartwool? We've found most of the products we tried from both brands were high-quality. In general, the fabrics on Icebreaker products tend to be silkier and softer, and Smartwool products tended to have more texture (but also more color and pattern options).
Merino Wool Clothing Reviews (By Brand)
I’ve been testing out various merino wool brands over the past few years. Overall I’ve been thrilled, but not every purchase was a win.
We got a small group of testers to try even more merino wool products. Here are some of the merino wool clothes we tried, listed by brand name in alphabetical order.
AllBirds makes shoes with merino wool uppers. Most of their shoes lean towards casualwear over activewear, but we still wanted to try them.
What we loved:
• Tree Breezers Knit Ballet Flats may have been the most comfortable ballet flats our testers have ever tried! We loved how breathable they are and the removable insole made them extra cushy. I'm curious to see how long they last, since the fabric top makes them seem more delicate. Also they do get dirty easily, but are washable.
What else we tried:
• The women's Wool Runners Sneakers were comfy at first, but quickly started to feel uncomfortable (for our testers). Also, despite the name, these are not running shoes, and don't hug your foot like an athletic shoe would. We later realized that Allbird's does make a more athletic style sneaker, but we haven't tried that one yet.
Branwyn is a new (to me) brand that sells merino wool bras and women’s undies.
What we loved:
• Their merino wool undies are also wonderful! They’re slightly less “sporty” looking than other merino undies we tried, and the fabric felt mid-weight.
What else we tried:
• Branwyn has a new "swag" clothing line. We tried the hoodie, but the fit just wasn't right for us.
Darn Tough is based in Vermont, and makes a nice variety of merino wool socks.
I love their cushioned hiking and mountaineering socks, as well as their thinner crew socks. Some of the patterns on these socks are pretty adorable too, Darn Tough currently has both a bear and squirrel print sock.
Icebreaker is a well-established merino wool brand that makes high-quality merino wool clothes. It's one of my favorite merino wool brands, and I've had many of the pieces listed below for years.
What we loved:
• Icebreaker wool undies for women: We tried multiple styles of their undies, and loved them all. The cuts are sporty and lightweight, and the percentage of merino wool is high (without lots of synthetics blended in). These are great for hiking and backpacking.
• Icebreaker socks: We tried a few different styles, and particularly liked their light or medium crew socks. For hiking I prefer a the medium weight sock.
• Icebreaker women's Tech Lite tshirt: This was our absolute favorite merino wool tshirt. It's 100% wool, survived (without shrinking) accidentally being put in the dryer for a full cycle, and fit well.
• Women’s 200 half-zip pullover: This pullover is a nice midweight top that’s perfect for layering. The fabric is extremely comfortable, and it's remained in great shape over many washings and multiple years.
• The Icebreaker 200 Oasis crew top is a light-weight, long-sleeved base layer. The fabric feels somewhat silky, and we love this as an extra layer when hiking on cold days.
• The Icebreaker 260 half-zip top (as opposed to the medium-heavy half-zip mentioned above) is heavy-weight, and is also great for pajamas when camping or backpacking in cold weather.
• Icebreaker merino wool jogger pants for women are my favorite merino wool pant. They’re comfy and warm, and I love them as camping pajama bottoms.
• These Icebreaker lounge shorts are so cozy! We love them as pajamas bottoms for summer camping.
• The Icebreaker high-rise shorts are my new favorite workout shorts! They're opaque enough to wear out of the house, and are also a great option for wearing under (knee length or longer) skirts in the heat to prevent thigh-chaffing.
• Icebreaker 200 base layer leggings make great base layers for cold weather. I like them as pajamas when it's extra-cold out. They're not fully opaque like workout leggings, so they're definitely meant to be worn as a base layer (under pants) or as pajamas.
• The Icebreaker headband is a merino wool headband for keeping your ears warm. It's warmer than some of the Buffs we've used in the past. This headband is soft and cozy, and fits a little more loosely than the Smartwool headband we tried. It currently seems to only come in solid colors.
• We also loved this Icebreaker flexi neck chute, and found it to be warm and cozy.
What else we tried:
• Icebreaker Quantum hoodie: Overall we liked this hoodie. It was a nice weight, fit well and comes in a nice range of colors. What stops us from recommending it? There's a front pocket that (for us) didn't lay flat, and the double zipper was extremely finicky.
• Icebreaker everyday women’s cami and the Icebreaker siren cami: Again, we liked these camis, but a few things made us feel that they may not be worth the price. First, the fabric on both was slightly coarser and itchier than other merino clothing we've tried. Also, the plastic strap adjusters concerned us, because we worried that these camis might not last for years.
• Icebreaker Sphere II t-shirt: This t-shirt was lightweight and perfect for working out in hot weather, but the merino wool percentage was fairly low (about 40%), and to us, the fabric felt more like our other synthetic blend athletic-wear tops. (I accidentally tumble-dried this top instead of line-drying as the care directions said, and it shrunk. A lot.)
What we tried:
• The Meriwool men’s boxer briefs were (impressively) 100% merino wool and were more affordable than others we tried. Our testers found these undies a little warm for day-to-day wearing, but they might be a good choice for colder days. Also, these undies didn't hold up to regular wear and tear, and developed runs in the fabric within a few months.
• The Meriwool T-shirt is comfy. Despite having a lightweight description, the t-shirt we tried was a bit thicker than some other brands (which was nice in the spring and fall). The t-shirt did seem to run small. (We tried a large, and it fit more like a medium, which was a shame since the large was the largest size available.)
What we loved:
• We also tried their hike light crew socks, which come in cuter prints than the classic hiking sock and are also fabulous socks. We did prefer the more cushiony classic socks for a more comfortable hike.
• Smartwool’s base layer tee is comfy and lightweight enough to wear in the summer heat. It does definitely look like athletic wear, but has a high merino wool percentage and performed really well.
• Smartwool's classic thermal crew base layer is a 250 heavy-weight thermal layer. It feels more sweater-like than the Icebreaker crew tops we tried (which felt silkier), but we found this shirt to be cozy and perfect for cold weather.
• We also loved these (extra warm and cozy) Smartwool classic thermal bottoms. Just like the matching crew top, these leggings are perfect for extremely cold base layering or for backpacking or camping pajamas.
• Smartwool training shorts are also great (even though, as mentioned, only the lining is wool). We preferred the Icebreaker high-rise shorts (especially in the heat) because it didn't have a synthetic outer layer, but found these Smartwool training shorts were also really nice for workouts.
• The Smartwool headband, another merino wool headband, is a little smaller than the Icebreaker one (so it might depend on how your head is shaped as to which you prefer). This one isn't quite as soft as the Icebreaker one, but comes in more colors and fun prints, and I like the texture. It seems like it will stay in place on my head longer than the Icebreaker one. (Currently I like both headbands and don't have a favorite.)
• Need more coverage than a headband? We found this Smartwool beanie to be extremely warm and comfortable.
• We especially loved this Smartwool Smartloft Women's Jacket. It fit well, was flattering, was (fairly) warm, and we really loved that it had thumb-holes on the arms. This jacket does have a somewhat lower merino wool percentage than we prefer, but we liked it so much that we decided it was okay.
What else we tried:
• I did not care for the Smartwool sport fleece wind tights that I tried (they ran small and were too long).
WoolX merino wool clothing comes in a variety of categories. I’ve owned a pair of their undies for years and am a fan, so I was excited to try more of their clothing options.
What we loved:
• Women’s undies: These seemed very similar to the Icebreaker undies! The fit, fabric and performance was fantastic. Additionally, these undies hold up well to regular wear and tear.
• Men’s boxers: Their men’s boxers were soft, comfy and breathed well! Our testers were impressed.
• WoolX hats, such as the Kaylee beanie and the Baylor beanie: The beanies were warm, cozy and cute. The Kaylee beanie was lined and warmer than the Baylor.
We initially loved almost all of the WoolX items we tried, but over time, have found that many of their items pill and show heavy wear after only light use. The items listed below as ones we like have not begun to show early wear and tear, but we still would hesitate before purchasing again.
What we still love (but worry about long-term wear and tear):
• Women’s long sleeve shirts: They make both lightweight and heavier shirts, and we loved them both.
• Men’s base camp hoodie: I was initially disappointed in this hoodie because I expected it to be thicker. (It's significantly thinner than the women's Ryann hoodie.) However, it's turned out to be a nice base layer and (so far) hasn't begun to pill.
What else we tried:
• Cushioned ankle sock: These were very soft and cozy, but less cushioned than the Smartwool socks. Sadly, the fabric on these socks began to pill after just a few wears.
• Addie short sleeve crew (Women's) was one of our favorite tshirts, at first. The fit was great, the fabric is soft, and this tshirt was just all-around fantastic. Sadly, we noticed that this shirt pilled when we wore it hiking with a backpack. In time (about 6 months of wearing about once or twice a week), we found that these shirts began to develop thin spots and holes where they rubbed against buttons on our shorts or pants. Unfortunately, this shirt just didn't hold up.
• Liza short sleeve crew (Women's) had cozy fabric, but the fit seemed to run large and we found the fit less flattering.
• Women's Ryann hoodie: This hoodie is a nice, medium-weight zipped hoodie. While it is fairly comfy, we found that the sleeves were too short and the hood was too small to actually use.
• Dani bike shorts: These workout shorts fit a little loose (similar to the Woolx leggings), and we found that the seams began to unravel on after a few wears. Also, these were slightly too constrictive to wear for workouts, and the synthetic outer layer meant they weren't breathable enough to wear under skirts in the heat.
• Merino Flex McKenna leggings: These leggings are a recycled synthetic material on the outside with wool lining, so they're fully opaque (but slightly less breathable than a fully wool legging). We tried both the full-length and capri version. They were comfy and fit well, but sadly after light to moderate wear (about 15-20 uses) the fabric on the inner leg had worn thin.
• Duralite Stella leggings: These ran a little big and (sadly) the fabric pilled on the leggings within a few hours. We ordered a second pair (just in case the first were defective), but these pilled quickly too. We definitely preferred the sturdier McKenna legging.
• The neck gator was soft, but began to pill after only light use.
Woolly Clothing Co.
Woolly Clothing Co. is based in Seattle and designs both activewear and casual clothes.
What we tried:
NatureDry LOFT women’s jacket: Woolly makes some pretty innovative jackets, like 100% wool all-weather winter coats. These are marketed as more natural alternatives to synthetic or chemically treated winter wear such as GoreTex or polyester.
I was excited to try this coat, and it does seem to do what they claim.
There was a lot that I liked about this coat: it’s warm, I liked the feel of the fabric, and the fit was good. However, for me, it’s unlikely to replace my other winter outerwear, because it’s slightly bulkier and heavier than I prefer.
Also, the pockets were small (too small to store a bulky glove) and didn’t zip shut (activewear coats really need zippers on the pockets!).
Women’s hipster brief undies: I’m not sure what happened here, but these ran huge. I ordered my usual size, and they were saggy and too big to wear.
We typically focus on outdoor gear, but I’ve heard a lot about Wool& and their merino wool dresses, and wanted to include them in this post.
A friend of mine is doing the 100-day wool dress challenge and is thrilled with her dress.
We tried two of their 160 gsm (lightweight) dresses. The majority of their dresses are lightweight.
My dress (the Fiona Fit and Flare) didn’t fit quite right. It was perfect in the shoulders but too loose in the upper body. I also found myself wishing it was slightly heavier fabric and a more structured fit.
For me, this wasn’t a win.
Another friend tried the Charlotte V-Neck Midi Dress, and while she found the fit flattering, the fabric felt slightly itchy to her.
So it's worth noting that even though most people find merino wool smooth and soft, if you have very sensitive skin it's possible you may still pick up on a bit of irritation.
I hope this guide has acquainted you with some of the nuts and bolts of shopping for merino wool clothes. And maybe you've already discovered a few of your own favorite items for outdoor wear — let me know in the comments!