Do Rash Vests Keep You Warm? What To Wear In Cold Water

Rash vests are a great options for protecting you from the harmful UV rays of the sun but when it comes to the cold water do rash vests actually keep you warm or what do you need to wear if you want to stay warm in the water?

Rash vests don’t keep you warm and should never be the sole source of heat retention. These thin, sleeved shirts are made of spandex and nylon or polyester and designed to protect the user from UV rays and abrasions. They do NOT to trap body heat or warmth and can have the opposite effect when exposed to wind. Wetsuits or wetsuit vests are recommended if you want to stay warm.

Rash vests do provide some warmth in certain circumstances, but this is primarily when it's very hot outside with little to no breeze. In these circumstances warmth isn't really required. Rash vests will also keep you warm if they are completely dry.

A black rash vest will keep you warmer than any other color as it'll absorb more of the sun's light and heat and warm up faster. A white rash vest will do the opposite and will be the coolest option to wear as it reflects the majority of the sun's light and heat.

However, when there is a cool breeze a wet rash vest (no matter what color) will actually make you colder than wearing no vest at all.

In this article, we’ll discuss the true purpose of rash vests and why anyone participating in water-related activities shouldn't rely on them for warmth. We'll also look at what swimwear and gear is specifically designed for the task of heat retention and will keep you warm even in the coldest water temperatures.

Why Don't Rash Vests Keep You Warm?

Long sleeve t-shirts keep you warm when it cold outside so you could assume that long sleeve rash vests would achieve the same thing when you're swimming right? Wrong!

While it might be easy to assume that rash vests will keep surfers, swimmers, and other water-loving individuals warm because they can cover most of their upper body, this assumption can’t be further from the truth.

Rash vests trap cold water against you skin. When exposed to the wind some of the water in the rash vest evaporates and this in turn cools down the remaining water on the vest.

The faster the wind the more pronounced this effect is and this means rash vests can actually make you colder than not wearing a vest at all.

Why Wear Rash Vests?

Rash vests are specifically designed for two overarching purposes:

  • UV sun protection
  • Rash prevention

Because of this, they optimize providing coverage and comfort over heat retention, especially since most are worn when temperatures are high, as that is when protection from sunburn is most vital. 

One of the greatest risks of being on the water is not only the direct sunlight that falls on your skin, but the amplified reflection of the sun off the water’s surface. Even on cloudy days harmful UV rays reach through the cloud and can burn your skin.

This is why surfers and other individuals on the water can bet sunburned easily even when there is minimal sunlight. 

Long exposure to the sun's UV rays can lead to sun burn and increase your chances of cancer. However, rash vests stop the majority of UV rays decreasing your skin's exposure.

Not only does the coverage rash vests provide ensure these harmful UV rays don’t reach the skin, but they also protect the skin underneath from potential injury, such as abrasions caused by surfing wax or chafing from a wetsuit. 

There is nothing worse than riding a foam bodyboard or surfboard without a rash shirt on and ending up getting a huge abrasion rash all over your stomach. You can certainly surf without a wetsuit but depending on what kind of board you ride you may or may not get a stomach rash.

Of course, it isn’t fair to say rash vests don’t provide any warmth. Despite their thin, skin-tight material, these garbs can be effective at providing coverage from chilly breezes when they are worn completely dry or when they are wet on a relatively warm day without much breeze.

If you’re facing cold water temperatures or cold external weather you might want to start considering something like a wetsuit or a neoprene insulated rash vest. 

What Should You Wear to Keep Warm Instead of a Rash Vest?

When the waves are roaring and the ocean calls, the last thing you want is to be held back because you don’t have the proper outfit to keep you warm.

Rash vests are great in summer for sun protection but there are much better options to keep you warm in and on the water. 

Depending on what kind of water sport your doing options to keep you warm include

  • Neoprene rash vests
  • Wetsuits
  • Dry suits (for extra cold water)
  • Water resistant jackets (if you won't be fully submerged in water…eg. Boating or Jet-skiing)

As you can see, some of these items are clearly more water-resistant or completely waterproof compared to others.

This is because common water-based activities where the individual has low-to-minimal exposure to water can wear more clothing-related layers versus those who are fully submersing in cold water. Surfers (like myself) usually choose to wear wetsuits in cold weather to keep themselves as warm as possible.

You can even wear extra clothing under a wetsuit for increasing warmth if you're going out on a really cold day and there are some really cool hacks for staying warmer in your wetsuit.

For the sake of this article, we’re going to discuss the benefits of each and what circumstances they’re best suited for using three of the most common water-based sports: sailing, surfing, and diving.


While sailors will certainly receive their fair splashes of water, they don’t usually intend to get as wet as surfers or divers.

Because of this, they can wear numerous layers to stay warm while sailing their vessel that will work significantly better than a thin rash vest. 

Typically, if a sailor knows they’re only fighting off a slight chill or even warm rains, they’ll opt for a comfortable sailing jacket.

These are a popular choice because they’re designed with multiple layers of material for additional warmth and insulation as well as being completely waterproof to ensure the users doesn’t lose precious body heat trying to warm up wet clothes. 

When sailing conditions take a turn for the freezing, most will break out their wool sweaters as a base layer and cover it with additional layers, such as jackets similar to sailing jackets made of merino wool or synthetic blends that are extremely water resistant. 

Wool is always an exceptional choice for warmth on the water because it doesn’t absorb body heat and is a moisture-wicking mater, meaning it can absorb a third of its weight in water before it starts feeling wet.

So, even if you encounter an unexpected wave or two, you can likely keep your cozy sweater on and still feel toasty. 

Surfing or Diving

Preparing for cold weather when you’re surfing or diving is an entirely different process than if you were sailing. These individuals are well aware that at some point, they’re going to be completely submerged in water, and therefore, they require completely waterproof attire to stay warm. 

In these cases, the best piece of water-related equipment any surfer, diver, swimmer or similar athlete could invest in is a wetsuit. 

Wetsuits are ingeniously designed to keep the user warm in a wide range of temperatures through a thick insulating layer of neoprene. The thicker the wetsuit, the warmer you’ll be, which is why individuals who like to surf or dive in a range of temperatures will likely own more than one wetsuit. 

While you can accessorize a quality wetsuit with a number of items, such as gloves and water shoes, the best option for those prioritizing warmth would be a wetsuit hood. These items are made of the same heat-retaining material as an ordinary wetsuit and can ensure excess body heat doesn’t leave your head in frigid conditions, which can make a world of difference in keeping you warm. 

Final Thoughts

Rash vests might look promising for keeping people warm at first glance, but in reality, they are nothing but a thin layer meant to protect your skin from a range of hazards you’ll encounter on and in the water.

If you’re looking for attire to keep you warm during your water-related activities, a wetsuit is almost always the best choice.

The exception being if you’re sailing or participating in some water sport where you rarely get wet. In these cases, insulted jackets made of wool or other quality materials are ideal.