If you’ve ever overheated halfway down a run or ended up shivering on a chairlift, you already know how important the right base layer is. It’s the first layer against your skin and the one responsible for keeping you warm, dry, and comfortable while skiing or snowboarding.
But here’s the big question: should you go with merino wool, synthetic fabrics, or cotton? Each has its reputation, but not all are made equal, especially in 2025 when performance and sustainability matter more than ever.
Cotton: Why It’s the Wrong Choice
Let’s start with cotton. We’ve all got drawers full of cotton t-shirts, so it’s tempting to throw one on as a base layer. But here’s the problem:
• Cotton soaks up sweat.
• It dries incredibly slowly.
• Once damp, it makes you cold, not cosy.
On the mountain, that’s a recipe for discomfort (or worse).
Verdict:
Cotton is fine for après-ski lounging but never for actual skiing or snowboarding.
Merino Wool: The Traditional Favourite
Merino wool has been popular with skiers for years.
Pros:
• Naturally warm, great at resisting odours, and helps regulate body temperature.
Cons:
• Can feel itchy, more expensive, slower to dry, and not suitable for those avoiding animal-derived products.
It’s a good option for multi-day touring or anyone who values natural fibres. But it’s not for everyone.
Verdict:
A strong choice if you want natural fibres, don’t mind the price, and wool works for your skin.
Synthetic Base Layers: The Modern Upgrade
Here’s where things get exciting: recycled synthetic fabrics.
Today’s recycled polyester blends are designed to perform in the toughest conditions:
• They wick sweat away from the skin faster than wool.
• They dry in no time, even after an intense run.
• They’re durable, stretchy, and comfortable.
• They’re eco-friendly, giving waste materials a second life.
And unlike older synthetics that trapped odours, new eco synthetics are built with odour-control tech.
Verdict:
If you want vegan-friendly, high-performing, sustainable recycled synthetics are hands down the winner.
Which Base Layer Should You Choose?
Here’s the no-nonsense answer:
Cotton:
• Never for snow sports.
Merino wool:
• If you can wear and don’t mind the price.
Recycled synthetics:
• The best balance of performance, comfort, and sustainability for most skiers and snowboarders.
How Tight Should a Thermal Layer Be?
Your base layer should fit snug like a second skin. A close fit helps with moisture transfer and insulation. If it’s too loose, sweat won’t wick away properly; too tight, and you’ll feel restricted. Look for stretchy fabrics that hug the body but still let you move freely.
Should You Size Up for Thermals?
Generally, no you don’t need to size up for thermals. They’re designed to be fitted. Stick to your usual size, and the fabric’s stretch will do the rest. If you’re between sizes, choose the one that feels comfortably snug without restricting movement.
Best Place to Buy Base Layers?
The best way to shop is online, where you’ll find a wider range of eco-friendly options. For performance-driven, sustainable gear, check out the Arctic Eco-Sno Base Layer Collection created from recycled materials designed for skiing, snowboarding, and cold-weather adventures.
Conclusion
When it comes to merino vs synthetic vs cotton, the choice is clear:
Cotton is out. It simply doesn’t work on the slopes.
Merino wool has its place, but it’s not for everyone.
Recycled synthetics are the clear winner, lightweight, quick-drying, affordable, vegan-friendly, and sustainable.