10 Best Base Layer Women 2025 in the United States

The Merino.tech Merino Wool Base Layer for women is a strong contender in the base layer category, particularly if you prioritize comfort and moisture management. Made from 100% superfine Merino wool, it offers a soft touch without the itchiness often associated with wool, making it suitable for all-day wear. The midweight fabric (250 g/m²) provides warmth without being overly bulky, which is perfect for various outdoor activities or layering in colder weather. One of the standout features is its moisture-wicking ability; Merino wool naturally absorbs sweat and allows it to evaporate, keeping you dry and fresh during strenuous activities. Additionally, its odor-resistant properties mean you can wear it for an extended time without worrying about unpleasant smells. The inclusion of wool socks adds value to the package, making it an attractive purchase for outdoor enthusiasts.

However, there are a few drawbacks to consider. While the fabric is durable and easy to care for with machine wash options, it may require more attention than synthetic materials, particularly if you want to maintain its longevity. Some users might also find the midweight option a bit heavy for more active pursuits in warmer climates. Lastly, while the product aims to cater to a broad audience, those with a strict budget may find the price point higher compared to synthetic alternatives. Despite these considerations, the Merino.tech base layer is well-suited for those who value performance and comfort in a base layer while enjoying the benefits of natural fabrics.

The Cuddl Duds Thermal Underwear for Women is designed to keep you warm in cold weather with its fleece-lined interior and heavyweight fabric. The set includes a thermal shirt top and leggings, both made from 93% polyester and 7% spandex, providing a snug yet comfortable fit thanks to its spandex stretch. This fabric blend ensures that the material is stretchy and durable while also offering protection against harmful UV rays with a 50+ UV rating.

The moisture-wicking properties help to absorb and evaporate sweat, which is essential for staying dry and comfortable during outdoor activities or layering under other clothing. The design includes thoughtful features such as thumbhole sleeves, modern rise leggings, and a tag-free label, enhancing comfort and usability.

This thermal set is machine washable, which adds convenience for regular use. Ideal for anyone needing a reliable, warm base layer for winter activities or lounging, this set combines style, functionality, and comfort effectively.

The Smartwool Women's Merino 250 Baselayer Crew is a solid choice for active women looking for a comfortable and functional base layer. Its merino wool material offers excellent odor control, ensuring you stay fresh during extended wear, which is a significant advantage for multi-sport activities. The fabric is also temperature regulating, meaning it can keep you warm when it's cold and cool when you're working up a sweat, making it versatile for various weather conditions.

One of the standout features is its lightweight design, weighing just 2 ounces, which makes it easy to layer under other clothing without adding bulk. The fit is designed to minimize chafing, a common concern for those engaging in intense physical activities, thereby enhancing comfort during wear.

The Smartwool Merino 250 Baselayer Crew is well-suited for active women who prioritize comfort, odor control, and temperature regulation in their base layers. Its lightweight feel and chafe-resistant design make it particularly appealing for multi-sport enthusiasts.