Merino

Women's merino underwear is more than a simple base layer: it's a thermoregulation system built from natural fibres. The weight of the wool, measured in grams per square metre, determines whether you stay comfortably cool in summer or well insulated on a winter ski day. Three factors matter most when buying: the right GSM weight for your activities, a close-to-skin fit for effective heat and moisture transfer, and mulesing-free merino that pairs quality with responsible sourcing.

The weight of the merino wool sets its warmth and versatility. Lighter weights around 160 g/m² are ideal for active women in moderate temperatures: they reliably regulate body temperature, wick moisture quickly, and suit hiking, light trail running, and warm-weather outdoor pursuits. A mid-weight at 200 g/m² delivers more warmth without sacrificing breathability, making it a strong choice for ski touring, snowshoeing, and general winter sport. If you're expecting extreme cold or planning lower-intensity activities, step up to the 260 g/m² option: this weight of merino base layer stays warm even in very low temperatures and works exceptionally well as ski underwear.

Merino ski underwear offers properties that synthetic alternatives struggle to match. The fibre actively manages body temperature — keeping you warm when you're stationary and releasing excess heat when you're moving hard. Its natural antimicrobial properties also prevent odours from building up, even after several days of wear. Odlo's merino ski base layers are made from mulesing-free wool in our own European manufacturing facilities, ensuring consistent quality and responsible production throughout.

With seamless merino underwear, the fabric is knitted directly into shape, eliminating the seams that can cause pressure or irritation during intense movement. The construction is body-mapped, meaning different zones are engineered specifically for warmth, ventilation, or freedom of movement. Sewn styles, on the other hand, allow for more design options, such as a half-zip collar for on-the-go temperature control. For high-load disciplines like cross-country skiing or ski touring, a merino-polyamide blend is worth considering: it combines wool's thermoregulation with the durability of synthetic fibres.

Merino base layers for women should fit close to the skin for the thermoregulation and moisture management to work at their best. Odlo offers two fits: Slim, which is next-to-skin — if you prefer a little more room, size up — and Fitted, which still sits close but allows slightly more movement and can be worn in your usual size. Merino t-shirts and tops, depending on their weight and cut, can also be worn as a visible layer rather than purely a base, which is a real advantage on multi-day trips when you're keeping your pack light.

Merino wool is more delicate than synthetic fabrics and needs a gentle approach. Hand wash or use your machine's delicate cycle at a maximum of 30°C, with a wool-specific detergent. Avoid fabric softener — it degrades the natural performance properties of the fibre. Because merino wool is naturally odour-resistant, you don't need to wash your base layers after every session; airing them out between uses is often enough. After washing, gently reshape the garment and dry it flat to prevent it from losing its shape. For more details explore our care guide.