I’ve worked in both surf shops and surf/windsurf centres and there are normally 2 different types of people who ask what do I wear under my wetsuit? Beginners who are renting or have just bought their first wetsuit, or someone looking to layer up to get warmer.
The quick answer to the question of what to wear under a wetsuit is – it can be either nothing at all, a thin garment like a rash vest, compression shorts or bikini for comfort or for extra warmth a thermal hooded rash vest. Whatever you choose to wear under your wetsuit, make sure it’s tight-fitting because anything baggy tends to bunch up and you normally end up with a self-inflicted wedgie.
What you decide to wear can also depend on the sport you intend to do. Sailors and paddleboarders might not get wet or fall in during the session, so they might have a fleece-like base layer under their long john style wetsuit. Whereas surfers and windsurfers may want to want to be toasty in the UK winters will have a thermal rash vest under their wetsuit.
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What to wear when renting a wetsuit
The only time I would always recommend wearing at least something under a wetsuit is when you’re renting.
If you are renting a wetsuit for the day then you should definitely wear something around the nether regions. Although rented suits are cleaned thoroughly, bacteria can still live in the neoprene (which is why wetsuits tend to smell so bad). Whilst I’m not a germaphobe, I just wouldn’t want my privates exposed like that, especially when the person who wore the suit before may have worn nothing at all.
Generally, rental suits are not that comfortable and tend to be quite scratchy around the neck area. So along with general hygiene, wearing something under the suit will make your session on the water more enjoyable.
So if you’re renting a wetsuit, use whatever you have available for you on the day, whether that’s swimming shorts, bikini, rash vest or even normal underwear. Anything is better than wearing nothing under a rental suit.
What to wear under a wetsuit you own
What you decide to wear under your own wetsuit will become clearer over time as you try new methods of either staying warm or for comfort. And what works best for someone else might not be perfect for you.
For me, I wear nothing under my wetsuit until it’s the UK winter, then I’ll wear a thermal hooded rash vest to keep my body and head warm if I’m windsurfing or surfing. When I’m paddle boarding on flat water I’ll (hopefully) not fall in, so in the winter I might wear a normal rash vest and compression shorts under my wetsuit to stop any chafing. On some days when it’s windy and snowing, I have doubled up and worn a summer wetsuit under my winter wetsuit to try to keep me as warm as possible. It kind of worked and I didn’t get cold, but it was almost impossible to move and everything felt very tight!
Nothing at all
If your wetsuit is decent and comfortable, you don’t have to wear anything under it.
Wetsuits are designed to trap a thin layer of water between you and your suit, your body then heats that water to help keep you warm. So in theory not wearing anything that can interfere with that layer will make your wetsuit work more efficiently. Also wearing anything under an already tight-fitting wetsuit will reduce flexibility, so if you want the maximum range of movement in your wetsuit, it’s probably best to wear nothing under it.
Compression shorts are meant to be worn during exercise to help reduce the risk of delayed muscle onset soreness, but they also double up as a really comfortable option to wear under your wetsuit. Because they are very tight-fitting, they don’t bunch up when putting on your wetsuit.
For any chap who owns, or wants to own a pair, speedos are another good option to wear under your wetsuit.
I’ve never worn thermal shorts under my wetsuit, but there have been times surfing in January when I’m sitting on my board and the water lapping around my crotch feels incredibly fresh.
So if you struggle with the cold and want your giblets warm, then I’d look at getting a decent pair of thermal shorts.
Bikini or Swimsuit
For the ladies, a simple bikini or swimsuit is the perfect option to wear under your wetsuit. Any beading or knots in ‘fashion’ type swimwear will be annoying, so look for simpler, sporty type swimsuits.
The swimsuit is mostly helpful for when you are getting changed in a public area, where its almost impossible to get your wetsuit off or on without exposing the top half of your body
A rash vest under a wetsuit is the go-to garment for many people, and it seems to be mostly people new to watersports who religiously wear one, even though it may decrease the efficiency of how your wetsuit heats the body.
I think that’s because they think a rash vest was designed to stop rashing under a wetsuit, but it actually meant to stop the rashing of wax on your skin when surfing.
So firstly if your someone who has always worn a rash vest under a wetsuit, maybe next time go without one, you might find the wetsuit is more comfortable and heats you up faster.
That being said, if your wetsuit is old, uncomfortable and chafes your neck, then a rash vest will help with that.
View our blog on best rash vests >
Thermal rash vest
What do you wear under a wetsuit in cold water? A normal rash vest won’t help at all with dealing with the cold, but a thermal rash vest is perfect to help keep you warm.
From short sleeves, long sleeves to hooded options, there are quite a few different styles of thermal rash vests, so that’s up to you to how much warmer you need to be.
Remember there is always a comprise and more layers or thicknesses will always result in less flexibility and movement in your wetsuit. But it’s worth the comprise if you can stay that little bit warm, which means you can be out on the water for longer and have more fun!
You might like to read our article reviewing women’s wetsuits
About the author
Watersports Pro is managed by Ollie, who has been in the industry since 2007. A paddleboard and advanced windsurfing instructor, Ollie has travelled the world teaching these sports.
Now based on the South Coast of England, he shares his experience and knowledge on watersportspro.co.uk.