25 Best Thermal Underwear for Men in 2022: Base Layers from Fear of God, Patagonia, and Smartwool

Long before the days of electric blankets (or electricity, period) the best thermal underwear for men was the only thing separating you from frostbite in the dead of winter. Their appeal is actually pretty simple: in winter you freely swaddle your upper half with coats, beanies, sweaters, and scarves, so why leave your legs out in the cold with nothing in the way of insulation beyond a layer of cotton or corduroy? Thankfully, we’re here to remedy the imbalance immediately. 

These days, thermal underwear isn’t exactly a necessity on most early winter days, but it’s precisely the type of product you’re going to be glad you own for those, ahem, truly brick moments in February—when polar vortexes descend upon your hometown and you can’t so much as scroll through your favorite meme page without your fingers going numb. Below, we’ve rounded up the best thermal underwear for men on the market today, from old-timey versions crafted of durable, always-acceptable cotton to the high-tech, moisture-wicking riffs you’ll sport under your snow gear while carving up a Black Diamond trail. 

The Best Entry-Level Long Underwear

Uniqlo Heattech extra warm crewneck long-sleeve T-shirt

Uniqlo Heattech extra warm long johns

At this stage, Uniqlo’s Heattech has, like Google and Kleenex before it, entered the common lexicon. As in, Oh, it’s going to be 20 below before windchill today? That’s Heattech weather. Or, You’re driving up to Quebec for that ski trip this weekend? Better stock up on Heattech. That ubiquity is well earned: the stuff is warm as hell, easy on the skin, and affordable enough to buy in bulk. These days, Uniqlo makes three levels of Heatteach gear—regular, Extra Warm, and Ultra Warm—and we’re fans of the middle option, which has a brushed lining for extra insulation but is still breathable enough that you won’t sweat bullets indoors.

The Best Long Underwear for Hitting the Slopes

Icebreaker 260 tech long sleeve crew

Icebreaker 260 tech leggings

If you’re planning on spending time on a mountain this winter—whether that means hiking up or skiing down—these are the ones you want. Fashioned from merino wool to ward off odors and regulate your body temperature, with flatlock seams to sidestep any chafing, Icebreaker’s technical base layers are engineered to keep you warm and comfortable on the move.

The Best Old-Fashioned Long Underwear

Hemen “Harri” henley

Hemen “Ikar” longjohns

When you imagine long underwear, these are probably what you picture first: heavy ribbed, button-fly henleys and long johns in heather gray and white. Hemen’s hardily-constructed organic cotton takes are as traditional as can be, but they’ll still be up to snuff heat-wise on your chilly morning commutes.

The Best Long Underwear to Luxuriate In

Hanro woolen silk long sleeve shirt

Hanro woolen silk longleg

On the awfulest winter days, when you wake up feeling extra gloomy, this set will serve as a worthy motivator to get you out of bed and moving in the right direction. Thanks to an opulent blend of merino and silk, they’re deceptively light and airy, feeling like absolute heaven against your body while still packing in the heat. Dropping nearly $300 on undies might seem crazy, but we’d argue that choosing to live in a cold climate isn’t totally sane, either. Treat yourself. You deserve it.

The Best Long Underwear You Can Wear on Their Own

Fear of God Essentials waffle thermal set

End Clothing

At the end of the day, thermal underwear is meant to be just that—underwear. So leave it to Fear of God’s Jerry Lorenzo to turn a pair of ultra-cozy waffle knit long johns into a henley-and-sweats combo you could—and should!—wear out of the house. They can still be worn as intended if you’re say, heading to the office (or any place, really, where hanging out in skivvies-adjacent loungewear is a no-go), but that slim silhouette means they’ll look just as rad under a topcoat and with a beanie when you run out to grab coffee on a milder winter day. The best part of the whole set? Those nifty pockets, so you can easily stash your keys, wallet, and phone on said early-morning coffee run.

15 More Pairs Worth Pulling On

The North Face winter warm leggings

Surprise, surprise: the outdoors-y experts at the North Face make a killer pair of long johns too, specifically designed to keep the wind out when you need them to and wick away sweat once you get moving.

Fjallraven “Bertagen” thinwool long johns

Lightweight merino means these will deliver max toastiness while still allowing for max breathability.

$100

Backcountry

Polo Ralph Lauren knit long john

For serious ‘Lo Heads who need everything to be pony’d out year-round, and folks who simply know that the Ralph stamp of approval still goes a long way, even on underwear.

Alpacas of Montana extreme warmth base layer bottoms

Don’t let their 100% alpaca wool construction fool you: These long johns are seriously technical, featuring 12 ergonomically-designed panels for flexibility and warmth.

$220

Alpacas of Montana

Hamilton and Hare thermal jersey long johns

Want the benefits of long johns but have sensitive skin that doesn’t play nice with wool? These silky lyocell-cotton joints are calling your name.

Bombas cotton modal long underwear

No tags, barely any seams, and a specially-designed waistband that won’t dig in or bunch up throughout the day.

Sunspel active merino long johns

If your idea of a winter workout is a skiing in Vail, these ultra-luxe, insanely soft Merino long johns deserve prime of place in your weekend bag.

Mack Weldon warmknit long underwear

Mack Weldon’s micro-waffle knit fabric is as hearty as the cold-weather breakfast food that inspired its name—and a whole lot easier to slip beneath your work pants.

$58

Mack Weldon

32 Degrees long underwear

Moisture-wicking long johns with just the right amount of stretch.

L.L.Bean double-layer underwear

Like a little wiggle room around your nether regions? L.L.Bean’s long underwear is made out of two layers of super-soft Lycra with flatlock seams that prevent bunching.

Land’s End thermaskin long underwear

If you’re worried about your gut expanding unduly over the course of a months-long hibernation on the couch, an elastic waistband—coupled with a soft, stretchy fabric for added flexibility—is the way to go.

Land’s End

Zimmerli tapered long johns

A wool-silk blend will help you retain body heat without suffocating your gams.

Tom Ford cotton long johns

Are these the warmest option on the list? No. Are they the most affordable? Also, no. But are they the absolute, capital-B boss-est pair on the market right now? Yes. Resoundingly so.

Tommy John sleekheat long johns

A touch of spandex means Tommy John’s undies will hug your body just so—without veering into Spanx territory.

$60

Tommy John

Smartwool Intraknit merino 250 thermal bottom

Smartwool’s performance-minded leggings may use an age-old fiber to get the job done, but it’s the innovative Intraknit tech behind it that really heats things up. They combine terry loops and mesh for a calculated combination of insulation and ventilation, all 3D-knit for a better fit and durability.

Indera Icetex pants

Indera has been making toasty undergarments in the USA since 1914, so they know what they’re doing. These guys are knit with a heavyweight cotton raschel knit on the outside and odor-resistant polyester fleece on the inside.

Patagonia Capilene Air base layer bottoms

Billed as Patagonia’s “most advanced” base layer ever, the Capilene Air traps warmth, dries swiftly, and keeps odors at bay even on multi-day camping trips.

Carhartt Force midweight thermal base layer pant

A tough, basic option at a killer price.

Tani SilkCut thermal underwear set

Cut from Micro Modal Air, a fabric fashioned from beech trees that’s purportedly thinner, stronger and softer than silk.