Best Thermal Bottoms for Men of 2025

The Heatwave Thermal Trousers are an essential addition to your winter wardrobe. This pack of two offers a 0.45 TOG rating, ensuring you stay warm by trapping more air close to your skin. The comfort fit, with its ribbed construction, shapes perfectly to your body contours, providing both warmth and comfort. Available in multiple colours, these thermal trousers are ideal as a baselayer, making them versatile for various outdoor activities or lounging at home.

The DOLCE ENVY Thermal Bottoms are designed to keep you warm and comfortable during winter activities. Made from a blend of cotton and polyester, these long johns feature heat preservation technology, ensuring you stay lightweight while minimising heat loss. The breathable materials help regulate your temperature, making them perfect for various activities. Additionally, these thermal bottoms effectively absorb sweat, keeping you dry and free from unpleasant odours, allowing you to focus on your adventures.

The Heat Stoke Thermal Long Johns are designed to keep you warm during the cold winter months. With a TOG rating of 0.45, these long johns effectively trap body heat, ensuring you stay comfortable. The brushed inside technology enhances cold resistance, providing extra warmth. Additionally, the ribbed construction fits your body perfectly, while the open fly design adds convenience. Made from a blend of 50% cotton and 50% polyester, these long johns are both soft and durable, making them an excellent choice for chilly days.

The Mountain Warehouse Thermal Trousers are designed to keep you warm and comfortable. Made from high-quality Merino wool, these trousers have natural antibacterial properties, ensuring you stay fresh during your outdoor activities. They actively wick moisture away from your body, helping you feel dry and comfortable even during intense exercise. Additionally, the quick-dry feature allows the fabric to dry rapidly, making them perfect for camping or hiking trips. With these trousers, you can enjoy your adventures without worrying about discomfort.

The DANISH ENDURANCE Long Johns are crafted from a midweight blend of antibacterial merino wool and polyamide, ensuring optimal warmth while keeping you dry through moisture-wicking properties. You can choose between versions with or without a fly for your comfort, and the superfine fibres provide a soft touch against your skin. Designed in collaboration with endurance athletes, these tights are perfect for outdoor activities like hiking and skiing, guaranteeing both quality and performance.

The Talus Thermal Baselayer Trousers from Mountain Warehouse are designed for outdoor enthusiasts like you. With Isotherm technology, these trousers retain heat while remaining light and comfortable. The moisture-wicking feature actively pulls sweat away from your body, keeping you dry during hikes or camping trips. Additionally, the quick-drying fabric ensures that even if you get wet, the trousers will dry swiftly, making them ideal for travel. Lightweight and easy to pack, these trousers are perfect for any active adventure.

The SIMIYA Thermal Long Johns offer exceptional fleece-lined comfort, ensuring you stay warm and cosy throughout the day. The unique free cutting design allows you to customise the leg length to your preference, providing a perfect fit. With double thickness knee fabrics, you can enjoy extra protection against the cold, making them ideal for outdoor activities like hiking and skiing. The 4-way stretch technology ensures you have complete freedom of movement, whether at the gym or relaxing at home.

The orbiz Thermal Trousers are designed for ultimate comfort and warmth. Made from a blend of cotton and polyester, these trousers are incredibly soft against your skin while allowing breathability to keep you fresh. The heat retention feature ensures you stay warm even in the coldest conditions, while the moisture-wicking properties help maintain a comfortable temperature. With their 4-way stretchy fabric, you'll enjoy flexibility that allows you to move freely without feeling restricted, making them perfect for outdoor activities.

The HIPOWER Thermal Long Johns are designed to keep you warm during the chilly winter months. Made from ultra-soft micro-fleece fabric, they fit snugly to minimise heat loss while remaining lightweight. The advanced 4-way stretch allows for excellent comfort and movement, making them perfect for activities like running or yoga. Additionally, their moisture-wicking properties ensure you stay dry by quickly drawing sweat away from your skin, providing you with a sense of security in cold weather.

The LE11 Thermal Trousers provide warmth and comfort with their ribbed construction that shapes to your body. Featuring a 0.45 TOG rating, these trousers effectively trap warm air close to your skin, ensuring you stay cosy during chilly days. Made from a blend of 50% cotton and 50% polyester, they are machine washable for added convenience. Available in various colours, these thermal trousers are perfect for layering under your clothes, providing you with an excellent baselayer option.