10 Best Base Layer Tops 2025 in the United States

The Under Armour Men's Armour HeatGear Compression Long-Sleeve T-Shirt in white and black, size X-Large, is designed for those seeking a high-performance base layer. Made from a blend of 84% Polyester and 16% Elastane, it offers a super-light HeatGear fabric that provides excellent coverage without adding bulk. This fabric is highly effective at wicking sweat and dries quickly, making it ideal for intense activities.

The mesh panels under the arms and on the back provide targeted ventilation to keep you cool. The ergonomic design enhances durability by keeping seams away from high abrasion areas, and the hybrid raglan sleeve construction allows for a greater range of motion and comfort. Additionally, it features a UPF 30 rating to protect your skin from the sun and a locker tag for personal identification.

However, the ultra-tight compression fit may not be comfortable for everyone, especially those who prefer a looser fit. The high polyester content might be less breathable compared to natural fibers. Despite these minor drawbacks, this T-shirt is a strong option for athletes or anyone needing a reliable moisture-wicking and durable base layer.

The Merino.tech Merino Wool Base Layer for Women is a versatile and comfortable choice in the base-layer tops category. Made from 100% superfine 17.5-micron Merino wool, it offers an incredibly soft and itch-free experience, making it ideal for all-day wear. This midweight shirt (250 g/m²) is suitable for varied weather conditions and includes moisture-wicking and odor-resistant properties to keep you dry and fresh throughout the day.

The natural ability of Merino wool to regulate body temperature ensures comfort year-round, making it a great option for outdoor activities like hiking or everyday use. The product comes with a pair of Merino wool hiking socks, adding value to the purchase. However, while the base layer is machine washable, it's recommended to hand wash and air dry for longevity, which might be slightly inconvenient for some users.

Additionally, the pull-on closure design is simple but may not be preferred by everyone who might seek a more adjustable fit. The product's light weight (4.8 ounces) and compact dimensions (10 x 9 x 0.7 inches) contribute to its ease of packing for travel. This base layer makes a thoughtful gift, thanks to its cool packaging and high-quality material. Backed by the Merino.tech Promise, customer satisfaction is a priority, ensuring a positive purchase experience.

The TELALEO 4 Pack Women's Compression Shirt is designed with performance in mind, making it a solid choice for athletes and active individuals. Made from 85% Polyester and 15% Spandex, these shirts offer a four-way stretch fabric that promises great compression support, enhancing muscle stability and flexibility. The snug fit is like a second skin; however, it’s recommended to order a size up if you prefer a less tight fit. This might be especially useful information for those new to compression wear.

The shirts are lightweight and quick-drying, ensuring comfort and focus during intense workouts without feeling weighed down. The moisture-wicking capability helps keep you dry, while the cooling effect provides comfort in various weather conditions. One potential drawback is that there’s no mention of specific odor control technology, which could be a concern for those engaging in particularly sweaty activities.

These shirts are versatile and can be used for a range of outdoor activities — from running and cycling to yoga. Easy to care for with machine wash instructions, they are convenient for daily use. These compression shirts could be a great addition to your athletic wardrobe, especially if you’re seeking support and comfort during physical activities.