10 Best Thermal Long Johns 2026 in the United States

The WEERTI Thermal Underwear for Men Long Johns is designed to be a reliable base layer for cold weather. Made from 92% polyester and 8% spandex, the material is lightweight yet offers warmth and comfort. The fleece lining helps in trapping body heat, making it suitable for layering under various types of clothing, from formal wear to casual outfits. The snug fit mimics a second skin, minimizing heat loss, while the 4-way stretch fabric ensures full mobility and flexibility without tearing the seams prematurely.

This is ideal for those who need comfortable yet durable thermal wear for both outdoor activities and lounging at home. The moisture-wicking feature is a significant advantage, keeping sweat at bay and maintaining dryness throughout the day, which is essential for staying comfortable in cold conditions. Additionally, the fabric's odor resistance helps in maintaining freshness after extended wear. However, a potential drawback is the polyester blend, which might not be as breathable as natural fibers like wool. Also, the fit being snug may not be suitable for everyone, particularly those who prefer a looser fit.

Nonetheless, these long johns offer a good balance of warmth, comfort, and functionality for cold weather use.

The Cuddl Duds Thermal Underwear set offers a cozy and practical option for women looking to stay warm in cold weather. Made from a polyester and spandex blend, it features a soft, brushed fleece interior that provides warmth without feeling bulky. The spandex content gives the top and leggings a comfortable stretch, making it easy to move around or layer under other clothing.

This set is designed to wick moisture away from your skin, helping to keep you dry during physical activity or throughout the day. It also offers added UV protection, which is a nice bonus if you spend time outdoors. The seamless design with a tag-free label and thumbholes in the sleeves adds to comfort by reducing irritation. Weighing just under 15 ounces, it’s lightweight enough to wear for extended periods without feeling heavy.

It is suitable as a base layer or worn on its own indoors, meeting the needs of anyone seeking warm, stretchy, moisture-managing thermal wear for everyday winter use.

The Carhartt Men's Force Midweight Waffle Base Layer Pant is designed with practical features that suit those seeking comfortable, performance-oriented thermal long johns. Made from 100% polyester with Carhartt’s Force technology, these pants excel at moisture-wicking and fast drying, which helps keep you dry during physical activities or cold weather wear. The midweight fabric offers a good balance—not too heavy for layering, yet warm enough for chilly conditions.

Fit-wise, the pants include a brushed elastic waistband with a contoured front and fly for added comfort and convenience. Flatlock seams are thoughtfully placed to minimize chafing, which is a nice plus for all-day wear. Additionally, the fabric fights odor, making these base layers suitable for extended use without smelling unpleasant. The pull-on closure style is simple but effective for easy wearing. One thing to keep in mind is the sizing advice: if you're between sizes, going larger is recommended to ensure a comfortable fit, which suggests the fit might run a bit snug.

These base layer pants are a solid choice for men needing reliable moisture management, comfort, and odor control in moderately cold weather, especially if you want something durable from a recognizable workwear brand.