Is There a Difference Between Long Johns and Thermals?

Is There a Difference Between Long Johns and Thermals?

The general term “long underwear” describes a two-piece base layer you wear in cold weather conditions. Whether you wear long underwear for physical outdoor activities or simply as an additional layer when going into the cold, they’re perfect for any winter weather.

You might hear the terms “long johns” and “thermal underwear” used interchangeably to describe long underwear. There’s a good reason this occurs because the two items are quite similar. When determining the difference between long johns and thermals, very few differences set the clothing materials apart.


There is a slight distinction between the materials of long johns and thermals. Traditionally, long johns consist of silk fabrics, while a scratchier, waffle-like material makes up thermal wear. However, both materials are incredibly high-quality and will protect your body in cold weather environments.


When trying to determine the differences between both clothing items, it’s a challenge to differentiate the terms because they are nearly the same. The difference in which words people choose depends on a couple of factors.

First, people tend to use the term “long johns” when referring to only warm pants. When you hear the word “long,” you think of legs and pants. Second, people think of both shirts and bottoms when they hear the term “thermals.” You might hear phrases such as “thermal shirts,” “thermal underwear,” and “thermal bottoms.”

Finally, some individuals prefer calling all cold-weather clothing items you wear beneath other clothing items “thermals” because it feels like a more appropriate and modern phrase. Additionally, they view “long johns” as an outdated name, which is why it isn’t as popular. While these clothing items are incredibly similar, many prefer the word “thermals” over “long johns.”

After concluding that there is only a slight difference between long johns and thermals, both clothing layers are ideal for any outdoor activity that requires a little extra warmth—whether you’re hiking, camping, or just going for a run outside. Since “long johns” and “thermals” are interchangeable terms, either type of men’s thermal long johns will withstand the test of winter weather during your outdoor activities.