When we made the decision to start move to our off grid homestead in the Pacific Northwest, we knew that we were in for some cold weather. Learning how to dress warm in winter, from head to toe, would be absolutely critical, and long underwear are a critical component of our wardrobe. Since it can be touch to find a great pair of long johns, I thought I’d what I’ve found to be the best thermal underwear for women.
To give you some background, I grew up in Southern California and I had no idea what it meant to be cold! My winter layers were pathetic at best, and if I put on any layers whatsoever I was warm because it just doesn’t get that cold in sunny Southern California!
Fast forward many years and I’m living in a climate that winters are actually winter. We have multiple days below zero, weeks in a row below freezing are not uncommon, snow on the ground all throughout winter is not unheard of, and working long days outside in the cold is common. Through trial and error, I’ve finally learned how to dress warm and it all starts with the base layer of thermal long underwear. This is the one thing you can add to your wardrobe that just may very well keep you warmer on a day-to-day basis.
I’ve tried on numerous brands of long underwear in my lifetime (most of them awkward!) but in order, here are my two favorites so far.
The Best Thermal Underwear for Women
1. SmartWool Merino Wool Long Underwear
Hands down, SmartWool is my #1 favorite brand of thermal underwear (and no, SmartWool did not pay me to endorse their product)!
Last winter, I was wearing as many layers as I could inside my home and it simply wasn’t enough. I purchased my first set of SmartWool thermal underwear and it was the best money spent all winter.
Many other thermal long underwear have crotches that are too long, waists that are too high, waists that result in muffin top, have fabric that is too thin which means I can’t walk around in my long underwear alone, and a number of other problems. SmartWool is not only made from one of the warmest materials out there (merino wool), but they are extremely soft, non-itchy, fit great, durable, are highly versatile, and they come in many neckline styles and patterns.
SmartWool Pros
- Warm
- Soft: These feel great next to my skin and are so comfortable that I sleep in them throughout winter. I basically never take them off because they are so comfortable.
- Durable: I’ve been wearing these for two winters now and they look as good as new! Not only that but I wear them when I’m working outside doing strenuous labor, they get washed frequently, and they’ve held up just fine.
- Don’t stretch out: While every set of clothing stretches out a little bit after each washing, these don’t stretch much at all. Even after a week of wearing them without washing, they still maintain great shape.
- Versatile: One of my complaints with thermal underwear in the past is that they don’t work when worn alone. Frequently, I would get too toasty and want to shed my outer layer, but as many long johns are see-through, that wasn’t an option. SmartWool long johns are versatile enough that they can be worn alone, modestly. They are even somewhat flattering and that can’t be said for 99% of long underwear.
SmartWool Cons
- Pricey: The only con to SmartWool long underwear is that they are more pricey than other sets of womens thermal underwear. Seeing that I wear them every day in the winter and they keep me warm, I personally am okay with the price as it is such a critical component to my wardrobe. However, I’d rather have one set of quality thermal underwear than three sets of unflattering, inefficient long johns.
2. Cuddl Duds Long Underwear

My second favorite set of women long johns are by Cuddl Duds. To be honest, I dislike the bottoms but LOVE the tops! If I want to wear a more fashionable long-sleeved t-shirt, then Cuddl Duds long underwear are great to wear underneath because they are a little thinner than SmartWool thermal underwear and have a more subtle neckline. If I’m working in a coffee shop or going out to dinner in winter, then I would prefer to wear my Cuddle Duds long underwear top under my clothing.
Cuddl Duds Pros
- Lightweight: These aren’t merino wool, but because they are 100% polyester, they are a little more lightweight which can be better for indoor use.
- Affordable: These thermal underwear sets are definitely affordable. Easy to stock up on a few tops so that laundry doesn’t have to be done so often!
- Fashionable: Again, these are great to wear day-to-day when you’re in a slightly warmer climate or doing strictly indoor activities.
Cuddl Duds Cons
- Not versatile: These are much less modest as a base layer. If you think you’re going to walk alone in them solo, think again! They look much more like underwear than a sturdy base-layer that can be worn solo if the need arises. I also don’t think they would look great as a base layer with a vest over the top.
- Pants are awkward: I have two sets of Cuddl Duds pants and they are both awkward. Maybe they work for some body types, but not mine! The waist band is too thin which results in looking less-than-flattering, and the crotch is a little too low which makes for a generally uncomfortable fit.
Top 5 Thermal Underwear for Women with Best Reviews
While I’ve tried on numerous brands of thermal underwear, I’ve by no means tried nearly enough! I’m sure there are other great fits out there that I’d like to try. Here are the top 5 brands of ladies long johns according to consumer data. I’ll probably pick one of these next if I ever feel the need to stray from SmartWool[/easyazon]!
{COMING SOON!}