The Best Long Underwear for 2025
Need new long underwear bottoms? We've been testing them for over a decade and showcase 16 of the best options in this review. Our team of experts spent months, in every season, taking these layers on river trips, ski slopes, and cold winter trail runs. We backed up our field research with objective, lab-style tests designed to analyze specific features of each pair of long johns.
It's hard to go wrong with Smartwool Classic Thermal Merino Bottoms. They add a serious warmth factor and are some of the most comfortable bottoms we have worn. If you are willing to invest, the Artilect Boulder 125 is a great ultralight choice that offers great breathability and drying speed.
If you want a complete set, our writeup on the best base layer tops can help you figure out what to pair with the bottoms reviewed here. Next, pick out some cozy socks, and you'll be well on your way to adventure-ready. If you need some new outer layers, a lightweight down jacket can be a good place to start.
Editor's Note: We updated this review on November 23, 2024, to add more information on our award recommendations.
Related: Best Long Underwear for Women