8 Best Long Underwear of 2026, Tested and Ranked

Heavyweight is on the label, but the surprise is how little room the Cuddl Duds set takes up. Under jeans it reads as warmth rather than as an extra layer, and that combination is exactly why it’s the women’s pick here.

The interior is brushed, and it is the softest thing in this group by a wide margin, close to a fleece pajama against the skin. The outside is smooth and slides under a sweater instead of grabbing it, and the fabric holds its color through washes. We also like that it works as loungewear: on a cold evening it’s a set you can wear on its own without feeling like you’re sitting around in underwear.

Sizing is the part to think about. The cut is generous, and the fit splits between true-to-size and a full size large. For a base layer that’s meant to sit close, take your usual size rather than sizing up. Sleeves and legs run long, which tall wearers will be glad of.

That generous cut is the one thing to plan around: if you’re petite, expect to turn a cuff and a hem. Everyone else gets a set that covers a cold commute, a ski weekend and a night on the sofa, and the premium price buys warmth per ounce that the cheaper women’s sets here can’t match.

Carhartt sells this as a single pant, not a set, and that shapes everything about it. You’re paying for one piece built for real cold instead of two built to a price, and the difference shows up the first time you pull it on.

The waffle knit is the old answer to cold and it still works. The texture traps air, so the fabric feels warm without much weight, and it stays comfortable when you’re moving rather than standing still. What we noticed most was the surface. It isn’t itchy, which is the usual complaint about heavy long johns, and it doesn’t chafe under work pants across a long day of bending and lifting.

Our verdict is that this is the bottom to buy if your cold is long and serious: a job site, a treestand, a driveway full of snow. It costs more than any other single piece here and you still have to supply a top. Where it has to earn that back is longevity, and that’s the open question, because the waffle is substantial but seams can split along the leg early.

Fit is where to be careful. These run big through the leg and seat, and the waist is the tight spot for some builds, so if you’re between sizes the smaller one is the safer bet. That is the opposite of what most sets here demand, which is worth remembering if you’re ordering more than one brand in the same week.

Pull the WEERTI set out of the bag and the inside is the first thing you notice. It’s a fleece closer to a hoodie lining than to technical base-layer fabric, and it changes how the thing feels at seven in the morning.

That lining is the whole pitch, and it delivers where it matters. Against skin on a cold start this is the set that feels least like a compromise, and the stretch means it moves with you instead of pulling across the back when you reach for something. Warmth lands right alongside the other midweight sets here, and it stays put under jeans rather than riding up at the waist.

The trade is that the fleece is a surface, not a thickness. It’s a midweight set, and in genuinely brutal weather it wants another layer over the top. The other thing to plan around is sizing, because it runs small through the torso and the shoulders bind first if you order your usual size.

We kept coming back to it for the feel, and that isn’t a small thing in a garment you wear against your skin for eight hours. If softness decides it for you, this is the set. If you want maximum warmth per inch and a harder-wearing weave, the Carhartt waffle does more, and the inner-thigh seams here are the part to watch over a couple of seasons.

For a base layer that has to live under office clothes, start here. The Amazon Essentials set is lighter and less expensive than our top pick, and it is the one that adds warmth without adding anything you can see through a shirt.

The waffle knit does the work. It holds a surprising amount of heat for something this thin, and it breathes enough that a warm train car doesn’t turn into a sauna. Under jeans the legs stay put and there’s no bunching at the ankle, which is more than we can say for some thicker sets in this group. It comes as a multipack too, which suits a work-week rotation.

Two things to know. The cuffs are the weak point: they don’t grip much, so sleeves can creep up under a sweater and the ankles can ride. And the sizing runs small and short, with the leg stopping below the calf on tall wearers, so if you’re over six feet this is not the set for you.

For everyone else it’s the value pick of the group for everyday wear, and the one we point to when someone wants warmth they can forget about by nine in the morning.

The SIMIYA set sits at the bottom of the price range in this group, and the first pleasant surprise is that it doesn’t feel like it. The outside is smooth and slightly silky, the inside has a light fleece, and it pulls on easily under jeans or scrubs.

Warmth is real but modest. It handles a cold commute, a chilly office and a winter walk, and this is the set we reached for when we wanted warmth without the feeling of being dressed for an expedition. It packs down small, which makes it an easy one to leave in a bag.

Our read is that it’s the best value in the women’s group. It costs the least, it layers under almost anything, and it’s soft enough that wearing it all day isn’t a chore. Just don’t ask it to be a midweight, because it isn’t one.

The catch is thickness. This is closer to a heavy pajama than a proper cold-weather base layer: fine if you’re moving or layered, less fine if you’re standing still in freezing air. The pants also run large for some builds, so check the chart rather than assuming your usual size will land.

The legs run long, and for anyone who has had a base layer ride up out of a boot, that’s the detail worth knowing. Fruit of the Loom cuts this bottom generously, long enough to tuck into a boot without pulling at the crotch, which is why tall wearers keep coming back to it.

The waffle is light in the hand, noticeably lighter than the Carhartt, but it still holds heat and the texture sits softly against skin instead of chafing. It packs to nothing, it dries fast, and it’s the pair we’d throw in a bag for a cold weekend without thinking about it.

Where it shows its price is the sewing. The stitching is the weak point, and it can let go along a seam within a few washes, with some material shedding after the first. The waist also runs big, so if you’re between sizes, take the smaller one.

What earns it a place here is cheap entry and that leg length. If you already own a top you like, or you want a spare bottom for a cabin trip without spending much, this is the pair. It isn’t the pair to build a decade of winters around, and it isn’t trying to be.

Two sets arrive in one order, which is the entire reason this one is on the list. One goes on, one goes in the wash, and you stop rationing a single base layer across a working week.

The sets themselves are better than the price per set suggests. Warmth is solid for a fleece-lined layer, the fabric is soft against skin with a smooth face that slides under trousers, and the fit is close without being restrictive. What surprised us is how little the fleece feels like a cheap lining after a couple of washes. For everyday rotation, it’s the most practical buy here.

Two caveats. Check what each set contains before you order, because the listing’s wording is looser than you’d like on that point. And the sizes run small, so going up one is the safer call, particularly through the shoulders and chest.