Best thermal underwear of 2023

That extra layer is all that stands between you and an unpleasant day outside.

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Not even the end of Game of Thrones can stop the inevitable march of winter, and if you live in certain sections of the country you know that baseline clothing doesn’t cut it when the temperatures start hitting “are you kidding me?” levels. You need something extra underneath it all to ensure Jack Frost doesn’t playfully nip at your extremities until they turn gangrenous and fall off.

So whether you like old-fashioned thermal underwear or are looking for something an Avenger might wear under their super-armor, you’ll find plenty of options. Here are some of the top.

Most comfortable: Thermajohn Ultra Thermal Underwear

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The 92 percent soft polyester construction will certainly keep you toasty, but it’s the remaining 8 percent that makes the difference here. Thermajohns use that extra percentage for spandex, which gives their underwear that extra bit of stretch that keeps you from feeling like a sausage casing. They are also constructed of moisture-wicking, odor-resistant material, and hug close to the body. The men’s style also has a traditional fly-front opening, which makes hasty trips to frozen restrooms much less of a struggle.

Most versatile: Pisiqi Thermal Underwear

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Featuring fleece-lined polyester, the sleek Pisqi thermal underwear may actually be too warm for anyone not stalking wild wolverines in the Yukon. Although slightly thicker to the touch than expected, they are designed to keep you from getting sweaty or clammy underneath, but note that the sizes run a little on the smaller side (so if you normally wear small, consider medium). Overall, these durable, form-fitting johns are great for those who plan on being a bit more active in the winter months, like skiers, or snowboarders.

Indoor warmth: Rocky Thermal Underwear

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Designed more like “traditional” long johns, these fleece-lined offerings come in a broad range of colors that suggest lounging around in front of a fireplace is an acceptable option. These are a great base layer that—thanks to the extra stitching around the cuffs—don’t bunch up under jeans so you end up looking like a sack of potatoes. Rocky also offers a full line of men’s, women’s, and children’s sizes.


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