6 Best Under Armour Thermal Underwear 2025 in the United States

The Under Armour Men's ColdGear® Base 4.0 Leggings are designed for extreme cold conditions, making them ideal for outdoor activities in harsh winter weather. The material is 100% polyester, which is durable and lightweight. The leggings feature a soft, brushed grid interior that traps air, keeping you warm and comfortable. They also have excellent moisture-wicking properties, ensuring that sweat is quickly drawn away from your skin to keep you dry.

The 4-way stretch construction allows for greater flexibility and movement in all directions, providing a comfortable fit without restricting motion. Additionally, the leggings include UA Scent Control Technology to minimize odor, which is a great feature for prolonged wear. These leggings are best suited for individuals who need reliable thermal wear for extreme cold, such as winter sports enthusiasts or those working in very cold environments.

The Under Armour Men's ColdGear® Base 3.0 Leggings are designed for cold weather activities, offering midweight warmth suitable for various activity levels. These leggings are made from 100% polyester, which contributes to their durability and lightweight feel. The soft brushed grid interior is a standout feature, as it helps trap air and maintain warmth, ensuring comfort during cold temperatures.

Additionally, the material wicks sweat and dries quickly, enhancing comfort during intense activities. Another benefit is the 4-way stretch construction, allowing for better movement in any direction. The performance elastic waistband ensures a snug fit without being restrictive. The leggings also feature UA Scent Control Technology, which helps keep odor at bay, making them ideal for prolonged use.

Despite these strengths, there are a couple of considerations. The product requires specific care instructions such as avoiding ironing, dry cleaning, and the use of softeners, which might be inconvenient for some users. Moreover, while the polyester material is durable, it may not be as breathable as some natural fibers. These leggings are best suited for individuals who engage in outdoor activities in cold weather and need reliable, moisture-wicking, and odor-resistant base layers that offer flexibility and warmth.

The Under Armour Men's ColdGear® Base 2.0 Leggings MD Black are designed for high activity in cool conditions. Made from 100% polyester, the material is lightweight yet durable, offering flexibility and breathability. The soft, brushed grid interior is excellent for trapping air and managing your body's microclimate, ensuring you stay warm and comfortable.

The leggings feature UA Scent Control Technology, which helps in odor resistance, making them suitable for long wear during various pursuits without the concern of bad smells. They also have moisture-wicking properties, allowing sweat to be effectively drawn away from your skin, keeping you dry and ensuring the material dries quickly. The 4-way stretch construction adds to the flexibility, allowing ease of movement in all directions, which is ideal for active use.

The performance elastic waistband ensures a snug fit without being too tight or uncomfortable. The care instructions are quite specific and require attention to maintain the fabric's quality, including machine washing with like colors and avoiding softeners and dry cleaning. The weight of the leggings is relatively light at 1.4 pounds, making them easy to wear without feeling bulky. These leggings are ideal for men who need reliable thermal underwear for activities in cooler weather, combining warmth, comfort, and durability with effective moisture and odor management.