Best Polyester Thermal Bottoms for Boys of 2025

The Orbiz Kids Thermal Bottoms are crafted from a soft blend of cotton and polyester, ensuring maximum comfort against your child's skin. They are perfect for keeping warm during school or sports activities, providing versatile performance for various occasions. With quick-dry fibres, you won't have to worry about sweat, as these thermals maintain comfort even during vigorous play. Designed to flex and stretch, they hug the body while allowing freedom of movement, making them ideal for active children.

The Indigo Soul Thermal Bottoms are perfect for keeping your child warm during winter. Designed as thermal underwear, these long johns offer a cosy and comfortable fit, making them ideal for chilly days. Crafted from a soft blend of 50% cotton and 50% polyester, they provide warmth without sacrificing comfort. Available in sizes for children aged 4 to 11 years, you can easily find the right fit for your child. Choose from classic black or white to suit their style.

The Sondico Thermal Sports Pants are designed to keep you warm during various sports activities, such as football, rugby, and skiing. Their full-length style provides complete coverage, ensuring comfort in cold weather. The elasticated waistband allows for a secure fit, giving you the freedom to move without restriction. Additionally, the compression fit helps support your muscles, making these pants ideal for active youths. You can easily maintain these trousers, as they are machine washable and made from a durable blend of polyester and elastane.

The Heatwave Boys Long Johns are ideal for keeping your little ones warm and comfortable during cold weather. Crafted from a blend of cotton and polyester, they provide excellent insulation with a TOG rating of 0.45. The moisture-wicking fabric ensures you stay dry and warm, even in temperatures below 30°F (0°C). With a soft fleece lining, these long johns are perfect for outdoor activities like skiing and camping, while the elastic seams allow for unrestricted movement, making them great for everyday wear.

The Floso Kids Thermal Pants are an excellent choice for keeping your little one warm during the winter months. Made from a blend of 50% cotton and 50% polyester, these thermal long johns provide great quality and comfort. The fully brushed interior adds an extra layer of softness, ensuring your child feels cosy throughout the day. Being machine washable, they are also easy to care for, making them a convenient addition to your child's wardrobe.

The DEVOPS Thermal Pants are designed to keep your child warm and comfortable. The micro fleece lining provides a soft touch against the skin, ensuring maximum comfort during wear. With added spandex, these pants offer extra stretch and shape retention, so they fit snugly and retain body heat effectively. Their versatile performance makes them ideal for both indoor activities and outdoor adventures, helping to keep your child warm no matter the setting. Plus, they are machine washable and quick-drying for easy care.

The Under Armour ColdGear Leggings are designed to provide lightweight warmth, perfect for chilly weather. You will appreciate how these leggings wick away sweat, keeping you comfortable during exercises. Their 4-way stretch construction allows for excellent flexibility, enabling you to move freely while working out. The dual-layer fabric features soft, brushed material on the inside for added warmth, while the smooth exterior ensures quick drying, keeping you warm and dry throughout your activities.

The Under Armour Thermal Leggings provide lightweight warmth, making them perfect for cold weather activities. You will appreciate how these leggings wick away sweat, keeping you dry and comfortable. With their 4-way stretch construction, you can enjoy unrestricted movement during workouts. The dual-layer fabric ensures you stay warm with a brushed interior while the smooth exterior dries quickly. These versatile leggings can be worn for running or under your clothes for added warmth.

The Under Armour ColdGear Leggings offer lightweight warmth, making them ideal for cold weather activities. You can enjoy amazing insulation without the bulk, as they are the weight of a t-shirt and effectively wick away sweat. The 4-way stretch construction allows for impressive flexibility, enabling you to move freely during workouts. Additionally, the dual-layer fabric ensures that you stay warm, with a brushed interior and a smooth exterior that dries quickly for added comfort.

The De feuilles Thermal Bottoms are designed to keep your children warm during chilly autumn and winter days. Made from a high-quality blend of fabrics, these trousers feature a soft fleece lining that provides extra warmth compared to standard long johns. The knee area is specially padded with wool and silk fibres, ensuring comfort and warmth where it's needed most. With a good level of elasticity, these bottoms offer a comfortable fit, making them perfect for both indoor and outdoor activities.