Top 9 Thermal Underwear for Women

This inexpensive two-piece set is the perfect base layer for those bitterly cold winter days. They’re lined with fleece to keep you warm and block out any weather-related moisture, plus the elastic waistband is super comfortable for layering. You can wear them under your clothes, as pajamas, or even for activewear, but no matter what, they’re guaranteed to keep you toasty.

If you're looking for a basic first layer, try this fleece-lined set of thermals. The form-fitting fabric is soft against your skin, and the flat seams won't rub at all. They're the perfect winter PJs, or they can be worn under clothes for a brisk night on the town. 

A blend of organic cotton and recycled polyester makes these waffle knit pants both comfy and functional. The high-waisted look of Hanes thermals make them a bit more fashionable, but their championing X-TEMP and FreshIQ Technology are the real stars. They're designed to respond to weather changes to maintain optimal body temperature so you never get too cold.

If you’re looking for the comfiest, coziest option on the market, then these thermals are a total necessity. This double-layer thermal material provides complete insulation and warmth. These pants are great for bearing the snow, or even just lounging around the house on a cozy day off.

These stretchy fleece leggings are totally amazing thanks to their flexibility, comfort, and warmth. Designed to hug your body in all the right ways, the super soft fabric makes Cuddl Fleece Underwear perfect for layering underneath other clothing items, ensuring that you’ll stay warm all winter long. Plus, the materialized blend of polyester and Spandex stretch alongside the curves of your legs, making them a total win.

These merino wool leggings work as a base layer, or on their own to keep you warm in cold weather. But you can keep wearing them when it warms up — merino wool is naturally breathable.

If exercising outdoors during the colder seasons is your main concern, then this set is right up your alley. The compression leggings provide an unmatched level of breathability (so you can wear them all day long!), and they’re lightweight and durable. An added bonus: their unique blend of fabrics pledges to allow free movement and provide air circulation so you never overheat.

Bodymapped clothes are designed to retain heat in some areas and release it in others — and it doesn’t hurt that the technical design makes this base layer look super legit. The stretchy jersey fits like a second skin and works best during high-intensity workouts like cross-country skiing, running, and cycling.

This four-way-stretch top has flat-lock seams that feel nonexistent next to your skin. It also features Columbia's Omni-Heat thermal technology that reflects your body heat back onto you, helping you keep warm when temperatures drop below freezing.