What to Wear Under a Wetsuit: Swimsuit, Rash Vest or Nothing?

Most surfers wear tight swim shorts or briefs, or a swimsuit or bikini, under a wetsuit. Some wear nothing at all in their own suit. Add a rash vest if the suit rubs, or a thermal top if you get cold. If you're in a rental suit at a surf school, always wear something underneath.

The longer answer depends on how well your suit fits, how cold the water is, and whose wetsuit it is.

If you're still choosing a suit, start with our wetsuit thickness guide. If it's your first week of lessons, our guide on what to expect at your first surf camp covers the rest of the day.

What are your options under a wetsuit?

There are seven realistic options, from nothing at all to a thermal top, and each one solves a different problem. The table sums up what wetsuit brands, surf schools and water sports shops say about each, plus the practical stuff they agree on.

Option	Pros	Cons	Best for
Nothing	No bulk, no bunching, the neoprene sits flat on your skin; quick to change	More rubbing at the neck, armpits and thighs for some people; not an option in a shared or rental suit for most; awkward to change on a busy beach	Your own well-fitting suit, if you're comfortable with it
Swimsuit or bikini	Sits flat if it fits well; you can fold the suit down to your waist and still be covered; what most surf schools ask for	Straps and ties can dig in under neoprene; loose or bulky pieces bunch	Lessons, surf camps, rental suits, most sessions
Swim briefs or jammers	Tight, so they don't ride up or bunch; a barrier against thigh rubbing	One more thing to dry	Men who want cover without bulk
Board shorts	You already own them; good for walking around afterwards	Baggy fabric bunches under the suit and can rub; brands advise against it	Wearing over the top after the session, not under the suit
Rash vest or lycra	Barrier against chafing, a thin layer of warmth, sun cover when worn without a wetsuit	Adds a layer the suit has to stretch over; dries slower than skin	Chafe-prone surfers, summer sessions, some surf parks that require one
Thermal or neoprene top	Extra warmth at the core, where brands say it counts most	Has to fit snugly or water pools in it; can make a tight suit tighter	Cold water, long sessions, surfers who feel the cold
Wetsuit socks	Warmer feet, some protection on cold sand and decks; quick to dry	Thin socks don't protect you from sharp rocks, reef or urchins	Cold days when you'd rather not go barefoot

Is it OK to wear nothing under a wetsuit?

Yes, in your own suit, and one wetsuit brand even calls it technically the best choice. Body Glove's reasoning is simple: neoprene keeps body heat in and cold water out, and anything between your skin and the suit gets in the way of that. It also points out that underwear, board shorts or a bikini can bunch up and stop the suit from sitting flat against you.

A British outdoor clothing brand lands somewhere in the middle. It notes that some people go without to cut bulk and move more freely, and that it speeds up changing, but adds that it "may not be as comfortable for everyone".

So it's a preference, not a rule. If your suit fits well and you don't mind the logistics of getting out of it on a beach, nothing works. If you share a suit, rent one, or simply feel better covered, wear swimwear.

Swimsuit, bikini or swim shorts: what works best?

Tight and flat beats loose and baggy, whatever you wear. The same brand guide says many men choose tight-fitting swim shorts and advises against baggy or bulky ones. For women it suggests a well-fitting full-coverage swimsuit or a bikini, which you can mix and match.

A women's water sports brand adds a useful detail: swimwear should sit flat and stay in place, and straps shouldn't dig in under the pressure of the neoprene. Think about where the straps and ties sit. A knot at the back of your neck can press into you for an hour and a half once the suit is zipped over it.

A Swiss water sports shop also warns against swimwear with metal buckles, zips or loose straps. You'll be lying on your chest to paddle, so anything hard or dangling gets old quickly.

Board shorts are the one item most guides steer you away from. They're baggy by design, and bunched fabric under neoprene is exactly what causes rubbing. Keep them for afterwards.

Where does a wetsuit chafe, and how do you stop it?

Chafing happens where the suit moves against your skin: the neck, armpits, stomach and inner thighs. A surf camp's guide lists those four areas, and a wetsuit brand names the neck, underarms and thighs as the spots "especially prone to irritation".

The causes they give are similar too: a suit that's too tight or too loose, folds and badly placed seams, and sand and salt trapped against your skin. Their advice comes down to a few steps:

• Fit first. Try the suit on before you buy it and check those high-rub areas. A snug fit reduces friction.
• Add a barrier. A rash vest or tight compression shorts sit between you and the neoprene. The British brand guide says simply that "a rash vest can stop any rashes occurring through chafing".
• Use an anti-chafe product. Both guides suggest applying one to the neck, underarms and inner thighs before you suit up. The surf camp guide notes that water-based or silicone-based lubricants are preferable because they don't degrade neoprene.
• Rinse. Rinse your skin and your suit with fresh water after every session to get the salt and sand out.

Rash vests were the standard fix in the past. Body Glove says they were common under wetsuits in the early 90s, mainly against seam rub, and that you rarely see them under a modern suit because glued, blind-stitched or taped seams have reduced the need. If you do get rubbed raw, the chafing guide suggests seeing a healthcare professional if there's swelling, worsening redness or signs of an allergic reaction.

Does wearing something underneath keep you warmer?

A thin layer can help, but only if it's snug; a loose one can make you colder. The British brand guide says a rash vest gives "a thin layer of warmth" and that full-coverage swimwear adds a little insulation.

For colder water, a women's wetsuit brand calls a thermal rash vest, with a brushed or fleece-lined inside, "the single most effective layer you can add under a wetsuit". It focuses on the core, where it says most body heat is lost. The catch is fit: "layers must be snug to work", because loose layers let water collect that your body then has to warm. In summer the same brand suggests a lightweight, quick-drying rash vest instead of a thermal one.

Body Glove's angle is different. It says many modern suits have heat-retaining linings built in, so you need extra layers less often, and it would rather you got the right thickness and a snug fit. Our wetsuit thickness guide helps you match the suit to the water, and our guide to cold-water surfing and how to stay warm covers boots, gloves and hoods.

Wetsuit socks sit somewhere in between. They're thin neoprene socks that one paddling brand says keep feet warm and dry in cold conditions and dry quickly. It also warns that they won't protect you from sharp rocks, reef or sea urchins. In the Netherlands, the Scheveningen surf school we checked includes neoprene accessories with its lessons and recommends booties, gloves and a cap with a 5/4 suit in winter.

What should you wear under a rental wetsuit at a surf school?

Swimwear, every time. It's what the schools ask for. A surf lesson booking platform tells you to bring "swimwear (swimsuit, swimming trunks, or bikini) to wear under your wetsuit", plus a towel, sunscreen and water. An inland surf park in England is just as clear: "You need to bring a swimming costume to wear underneath your wetsuit and a towel to get dry after your surf." One Australian surf school keeps it even shorter: bring your swimwear and a towel.

Some places go further. A Swiss surf park says that in summer you can surf in just a swimsuit but must add a lycra, and that lycra is essential in every season. Its coaches hand them out at the start of each session. That's a rule at one park, not a general one, so check with your school before you go.

We couldn't find a surf school that publishes how it washes its rental suits, so we won't guess. What we can say is that a wetsuit brand describes an underlayer as a practical choice for rental suits and suggests quick-drying fabrics. Your own swimwear between you and a suit that someone else wore yesterday just makes sense.

A surf camp week usually means a shared bathroom and a wet bag that never quite dries, so keep the rest of your kit small. One solid bar for hair, body and face is one thing to remember instead of three bottles, and there's nothing to leak into your swimwear.

Our surf trip packing list has the full list for a week away.

How do you change into and out of a wetsuit on the beach?

A changing robe or a big towel, plus swimwear underneath, makes it easy. Body Glove recommends a towel or a changing robe for getting into a suit on the beach. The British brand guide notes that tight swim shorts make changing simpler, and that with a swimsuit you can walk down to the water with the top half of your suit folded down.

A few practical habits help, whatever beach you're on:

• Stand on something: a changing mat, the robe's hem or a towel keeps sand out of the suit.
• Put your swimwear on at home or in the accommodation, so you only have to deal with the suit at the beach.
• Peel the suit down to your waist first, put the robe on, then take the rest off underneath it.

We couldn't find official rules on changing at the beach in the Netherlands, Belgium or France to quote here, so we'll stick to the practical point: wearing swimwear under your suit means you're never fully undressed, which keeps it simple on any beach.

What should you not wear under a wetsuit?

Cotton, anything baggy, and anything with hard bits. A Swiss water sports shop puts it plainly: "No cotton underwear underneath, as it stays wet and becomes uncomfortable under neoprene." Wetsuit and swimwear brands recommend synthetic, quick-drying fabrics such as nylon and polyester instead.

• Cotton underwear or T-shirts. They stay wet and heavy.
• Baggy board shorts. They bunch and rub.
• Swimwear with metal buckles, zips or loose straps. They press into you or snag.
• Loose layers of any kind. Water collects in them and you get colder, not warmer.

What should you do after the session?

Rinse the suit in fresh water, rinse yourself, and get everything dry. O'Neill tells you to rinse your suit inside and out with cold or lukewarm water after every surf, until the sand, salt and dirt are gone, and never with hot water. Patagonia's advice is to let the water run down the neck and out of the legs when you can, and to wash it out with fresh water as soon as you get home: "The quicker you can get to a rinse the better."

Both brands want it dried inside out in the shade, because UV damages the rubber. O'Neill adds: use a wide plastic hanger rather than a wire one, don't fold it, keep it away from car boots and heat, and clean it with a wetsuit-specific product every 3 to 5 sessions. Patagonia warns that a wet suit left in a parked car gets musty. If yours already smells, our guide on how to get rid of wetsuit smell goes deeper.

Your swimwear or rash vest needs the same treatment. The British brand guide says to rinse it in fresh water, skip harsh detergents and hang it to dry out of direct sun.

Then it's your turn. Beach showers are for sand and salt. Don't rinse shampoo or soap directly into the ocean or into beach showers that drain to the sea. Lather only where the water goes into a drain. Our guide on how to rinse off after a surf covers the quick beach rinse and the proper shower later, and our guide to surf camp showers helps with shared bathrooms.

A proper shower after a session is where a bar is handy: it goes into a damp wash bag next to your wet swimwear without leaking, and it does hair, body and face in one.

Then hang the suit and your swimwear up, and you're ready for tomorrow.

Packing for a surf trip: what goes in the bag?

Two sets of swimwear, a rash vest, a towel or robe, and a wash kit that doesn't mind being damp. Two sets means one can dry while you wear the other.

For the wash kit, think small and solid. A bar for hair, body and face isn't a liquid at airport security and takes up less room than bottles. Our guide to a carry-on surf trip wash kit has the details, and if you're surfing closer to home, our guide to surfing in the Netherlands and Belgium covers the local spots.

With the kit sorted, all that's left is the water.

Summary

Wear tight swim shorts, briefs, a swimsuit or a bikini under your wetsuit, or nothing in your own suit if you prefer. Add a rash vest against chafing, a snug thermal top for cold water, and always wear swimwear under a rental suit at a surf school. Skip cotton and baggy shorts. Afterwards, rinse the suit in fresh water and dry it inside out in the shade, then wash yourself where the water goes into a drain. See our wetsuit thickness guide, how to rinse off after a surf and surf trip packing list for the next steps.

Frequently asked questions

Sources

The facts in this article are based on the sources below, checked in October 2026.

1. What to wear under your wetsuit. Body Glove, 2026.
2. What should I wear under my wetsuit?. Finisterre, 2026.
3. The ultimate guide to layering under your wetsuit. Wallien, 2026.
4. Do you wear anything under a wetsuit?. Sharkskin, 2026.
5. How to prevent and manage wetsuit chafing. Sharkskin, 2026.
6. Say goodbye to wetsuit rash with these proven solutions. Rapture Surfcamps, 2026.
7. What do I wear under the wetsuit?. Outdoor Switzerland, 2026.
8. What are wetsuit socks and do they work?. Vaikobi, 2026.
9. What do I need to bring for my surf lesson?. CheckYeti, 2026.
10. Surfboards and wetsuits. The Wave, 2026.
11. FAQs. Let's Go Surfing, 2026.
12. What do I need to wear to surf at Alaïa Bay?. Alaïa, 2026.
13. Frequently asked questions. Hart Beach, 2026.
14. Wetsuit care instructions: how to wash and clean your wetsuit. O'Neill, 2026.
15. How to clean a wetsuit: remove odor and grime. Patagonia, 2026.