Pick the wrong ski base layer and nothing on top can save you. You sweat on the climb, freeze on the chairlift and spend the afternoon arguing with your own jacket. Pick the right fabric and fit, and you’ll forget you’re wearing it.
To keep things simple, we’ve created a guide to all things Merino wool base layer: what it is, how it compares to synthetics, and how to choose the right warmth and fit for your mission. Because you can’t control the weather, but you can control the chilly sweat patch that sends you packing.
What is a Merino ski base layer (and how is it different from thermals)?
A base layer is the layer that sits next to your skin. Its job is to pull sweat away from your body and keep your temperature steady while you move, pause and cool down. Merino ‘thermals’ is the everyday word for the same idea. Tomato, potato. What separates a good one from a bad one is the fabric.
A Merino base layer uses fine Merino wool, a natural fibre that works in both directions: cool when it’s hot, warm when it’s not. It wicks sweat, dries quickly and resists odour, keeping you on the slopes for longer.
Merino wool thermal underwear, leggings, hoods, zip necks, socks and balaclavas all do the same job. Sit close, manage moisture, let the good times roll.
Merino vs synthetic base layers
Synthetic base layers move sweat. Merino takes it to the next level, taking on vapour and releasing it instead of leaving it sitting damp against your skin. A four-year study led by NC State University and The Woolmark Company proved what we already knew: Merino outperforms polyester in moisture buffering by 96%.
Odour is the other gap. Merino resists it naturally, so your base layer stays fresher for longer than most synthetics. And because Merino regulates heat as well as moisture, you’re less likely to be stripping layers on the climb, dragging them around, then pulling them back on at the top.
We’re not here to bash anyone’s kit. Merino just does the job better, and the science backs it up.
What is the best Merino base layer for skiing and snowboarding?
Ski days run hot and cold. You push hard on the climb, then sit still on a chairlift in the wind. Sweat, storms and chills, Merino ski base layers handle all three like a champ. But which one is the best?
The short answer: it depends on the weather. Cascade is your go-to for winter days, and our most popular base layer for a reason. When the weather gets moody, step up to Olympus. And when it’s well below freezing from sunrise to last call, reach for Ascender.
Whatever you choose, don’t forget your legs. Cascade, Olympus and Ascender all come as bottoms, so you can run the same warmth level top to toe.
Choosing base layer warmth: warm, warmer, warmest
Our warmth finder splits the range into three levels. Pick the one that matches the conditions, and you’re done.
Warm: Cascade
Your daily driver for winter days.
Our most popular and versatile base layer. Cascade covers most days on the mountain, with all the warmth of 180gsm Merino wool (81% Merino, 12% nylon, 7% elastane). The four-way stretch keeps its shape and moves with you when you ride, and thumb loops hold the sleeves in place. From cool winter days to Aperols at après, it’s the one most people reach for most days.
Warmer: Olympus
A level up for when the weather turns.
Olympus is the layer you’ll reach for when the forecast looks variable. Midweight 250gsm Merino (96% Merino, 4% elastane) and underarm mesh panels give you a warmer layer that regulates your core temperature and wicks sweat. Warm and dry, whatever the weather brings.
Warmest: Ascender
Our warmest layer for the coldest days.
Meet Ascender, our warmest base layer yet. Seamless construction builds ventilation zones right into the fabric, so it’s thermo-mapped to breathe, stretch and mould to your body. It keeps you warm on storm days, without the scratch of seams. Ascender is a Merino and Tencel™ blend: 48% Merino wool, 26% polyamide, 21% lyocell and 5% elastane.
Not sure which to pick? Start with Cascade. It’s our best-seller for a reason. Alternatively, if you’re after a more lightweight base layer for shoulder season or spring ski touring, the Temple (men’s) and Bella (women’s) have you covered. They also double as a hiking layer in summer. Perks of versatile Merino, and all that.
Choosing base layer fit
Choosing the right base layer fit is important. Our men’s Merino base layers and women’s Merino base layers come in a few different fits: slim suits high-output days and lets you layer up under a shell without the bulk. Standard fits a little looser for easy wearing on and off the mountain. Cascade, Olympus, and Ascender are designed in a slim fit, while the Yotei is our original loose-fitting standard fit base layer.
When you're choosing base layer fit, check the size guide and use our size finder tool to find the size best suited to you. You'll find this on our base layer product pages.
How to layer
A base layer is step one, not the whole system. Each layer needs to work together to maintain the benefits of Merino wool, then bring in the extra insulation and waterproof shell as the weather requests.
Here’s how the Merino layer system builds:
- Base layer: Starts next to your skin and sets the tone for your day. Think Cascade, Olympus or Ascender. See men’s and women’s.
- Mid layer: Works with your base system to add extra warmth on colder days. Lightweight, breathable Merino warmth that packs small. See men’s and women’s.
- Active insulation: When things go sub-zero, swap out your mid layer or throw it on top. See men’s and women’s.
- Neckwear and accessories: Beanies, balaclavas, neckwear and gloves cover the places you lose warmth first.
- Waterproof shell: Keeps out wind, snow and rain on those average days. Look for high waterproof ratings, pit zips, helmet-friendly hoods and sealed seams.
Get the full breakdown in our Winter Layering Guide. Check the weather, choose your layer, get outside.
