Best Thermal Underwear T-Shirts for Men of 2026

"I bought this shirt mainly for its quick-drying and lightweight qualities to use as a cycling base layer, and it’s become one of my favorite shirts for lounging around the house. The fit isn’t too tight, which I love, and despite the affordable price, it's great quality and keeps me warm."

"I used to wear traditional thermals, but after finding these, they’re now my top choice for a base layer. They’re lightweight, yet surprisingly warm, and the quality is super soft—I even ordered more after my first one!"

"These shirts are perfect for our Texas weather—very light and comfortable. My whole family uses them for an extra layer in winter without feeling weighed down."

"I was really impressed by how these shirts stayed fresh and odor-free even after wearing them all day while traveling. The merino wool fabric was thin yet effective, keeping me comfortable in both warm and cool conditions. I appreciated the softness—never itchy—and how quickly the shirts dried after washing. My only small complaint is that the washing instructions were a bit unclear, but I used my best judgment and had no issues. Overall, I’m very happy with this purchase and definitely plan to buy more."

"I picked up a Merino.tech shirt for cold-weather layering, and the fit and comfort exceeded my expectations. As someone with an average build, it fits just like my favorite undershirts but is noticeably warmer than cotton. The material feels smooth and well-crafted. Plus, it came with a great pair of merino wool socks. Highly recommend for anyone wanting a quality, lightweight base layer."

"After trying several merino wool brands, I found that Merino.tech shirts stand out for their quality and durability. Wearing one under my work shirts, I stayed dry and odor-free regardless of the weather. The fabric and stitching are solid, though I did find the tags a bit noticeable. Still, the overall comfort and performance make this a shirt I’ll buy again."

"I bought this long-sleeve tee as a Christmas present for my dad, and it turned out to be a fantastic gift. The shirt arrived quickly, the quality matched the description, and my dad said the fit was just right—not baggy, not snug. I appreciate how it can be dressed up or kept casual. I'll definitely check out more options from this brand!"

"This shirt is now my husband's absolute favorite. He finds it incredibly comfortable and soft, and it's become his go-to for casual wear. The quality really stands out, and it looks great on him!"

"Although I found the fit a bit too snug and the material thinner than expected, I have to mention the outstanding customer service from Yrue Fit. They reached out, offered a full refund with no hassle, and left me genuinely impressed with how they handled everything."

"I'm really impressed with the super soft fabric and perfect fit—that’s rare to find in this style of shirt. The quality feels great, and it’s now my go-to piece for cooler days."

"I appreciate that these shirts are budget-friendly while still looking sharp and stylish. The design is simple yet dressy, and I love that I didn’t have to iron it after washing. Fits wonderfully and feels fantastic!"

"I’ve become a fan of this brand—they offer vibrant colors and true sizing, and I own several of their shirt styles now. This ribbed thermal isn’t just warm, it’s stylish and comfortable. I’m genuinely happy with my purchase."

"I found the fabric to be incredibly soft and comfortable, and the fit was just right. The stylish appearance is a bonus, and it keeps me warm without feeling bulky."

"This turtleneck is a great value for the price. It’s warm, durable, and works well with both casual and dress pants. I’ve had several people compliment me while wearing it."

"The material is thick and almost felt-like, which makes it feel very nice against the skin. I also appreciate that the turtleneck is long enough to cover my cheeks and nose on colder days."

"I've been wearing merino wool for years, and after trying the Merino Protect T-shirt, I was blown away by how well it kept me cool, even in 100-degree heat. It outperformed both a regular cotton T-shirt and another merino brand when it came to ventilation and comfort. The difference was so noticeable that I ended up returning the other brand. This shirt is now my go-to for travel and hot weather, combining all the benefits of merino wool with a design that really delivers on breathability."

"I bought this shirt for a wedding trip to Saudi Arabia, and it really proved itself in extreme heat. I wore it for over 20 hours of travel and then out in the afternoon sun, and it stayed nearly odorless the whole time—even my wife was amazed. Plus, it held its shape after washing, unlike a more expensive alternative. It’s become my hot weather solution, and I appreciate that it’s reasonably priced and long-lasting. Just be careful with stains, but overall, I’m thoroughly impressed."

"I’ve switched over to these Merino Protect T-shirts for all my workouts and daily wear. They’re soft, stretchy, and never itchy, and the fit is just right for my build. I especially like how well they work for activities like hot yoga, where odor and comfort really matter. These shirts feel more premium than any cotton or synthetic option I’ve worn—can’t wait to see what new colors or styles come out next!"

"I was initially skeptical about wool shirts, but after wearing this one in the hot Rio Grande Valley while sweating profusely, I was genuinely impressed. It stayed comfortable, dried quickly, and had no odor even after multiple wears. Sizing up was perfect for me, and I love that I can easily hand wash it and have it dry by morning."

"I've become a huge fan of Merino wool, especially after realizing how warm, itch-free, and odor-resistant these shirts are. I can wear them several times between washes, and I appreciate that they're machine washable and dryer safe. Honestly, it's hard to go back to cotton or synthetics now."

"I use these shirts every day for workouts, and the comfort is top-notch. I toss them in the washing machine, but have learned to air dry them to prevent shrinkage. They're super soft, though I wish they held up better over time."

"I was really impressed with the softness and comfort of this shirt. Despite the thin material, it keeps me warm without bulk and fits just right. The attention to detail, especially on the button placket, is impressive, especially for the price. I’m planning to get more in other colors."

"I bought this shirt for my son and he loves how extremely soft it feels. The fit was true to size and there were no issues with shrinking after washing. For the price, it’s a great deal and looks good, too."

"The value is unbeatable—the shirt fits perfectly, feels nice and soft, and the length is right. I highly recommend it, and my grandson already wants more in different colors!"

"I'm about 6' tall and 160 pounds, and the medium fits me well. The material is soft, a bit stretchy, and very comfortable. I like that it has a slim fit and the grey color is nicely done. It is a little longer than I expected, so I usually tuck it in."

"I bought this for my husband who is 6'1 and 240 pounds, and the XXL fit him perfectly. The quality is impressive, and the material feels soft and buttery."

"The fit and fabric are great, and it's incredibly comfortable to wear. Plus, I got it at a good price, which makes it even better."

"I found these shirts to be a great deal, offering a comfortable fit and very soft fabric. They're easy to care for and ideal for travel, thanks to their lightweight and packable design."

"The sizing is a bit off, so I'm glad I chose a size down from what I usually wear. They do run a little big for my frame."

"For the price, these mock turtlenecks are better than basic tees and provide extra warmth in winter. However, there are some minor issues like tags that irritate and seams that are slightly misaligned, so I just wear them for casual or home use."