The best way to prevent surf rash is to remove the friction before it starts. Wear a snug rash guard, keep sand out of your wax and off your skin, put a thin layer of balm on the spots that rub, and rinse with fresh water as soon as you are out. Most rash comes from the same few habits, so most of it is fixable in a single session.

We teach first-timers every day in Waikiki and on the North Shore, and the pattern repeats: people paddle hard, lie on a waxed board and sit up and down for an hour, then notice their ribs or armpits burning in the shower. This guide covers where rash shows up, why it happens, what to wear, how to treat a scrape and when to see a professional.

TL;DR

• Surf rash is friction damage between your skin and the board, wetsuit or shorts. It is not contagious, and it is largely preventable.
• A snug rash guard is the foundation. Under a wetsuit, it goes directly against your skin with nothing beneath it.
• Add a thin layer of balm made for neoprene on armpits, neck, inner thighs and ribs, and keep sand out of your wax.
• Rinse off, wash the scrape gently and keep it clean. See a health care provider for signs of infection, a large wound or an out-of-date tetanus shot.

Table of Contents

• What surf rash is and where it shows up
• Why it happens
• Wear the right layer
• Use balm on the hot spots
• Technique and board habits that reduce friction
• Care for your gear between sessions
• If you already have a rash
• Our perspective on surf rash
• Ready to get in the water comfortably?
• FAQ
• Sources

What surf rash is and where it shows up

Surf rash is skin abrasion from repeated rubbing while you surf, bodyboard or ride other waves. It runs from sore, red skin to deep, bleeding cuts if left untreated. It is a physical reaction to friction between skin and wet gear, not a contagious disease.

Dermatology literature has a name for the chest version: surf rider’s dermatitis, an irritant contact dermatitis in surfers and bodyboarders. It shows up as painful red, swollen nipples with small abrasions and fissures, caused by friction, shearing and pressure between body and board. A review of contact dermatitis in athletes adds that sand, salt water, wind and the board itself all contribute.

The usual trouble spots follow your movement on the board:

Rib cage, armpits and inner thighs are the most commonly affected board rash areas, and the neck, stomach and inner thighs are prone to wetsuit rash from repeated movement between suit, board and skin.

Why it happens

Knowing the cause tells you which fix to use.

Wax and sand. Wax grips your feet, but it also holds sand. Sand in wax turns the deck into sandpaper under your belly. If you are curious how wax works, our guide to why surf wax matters explains the grip side. For rash, the lesson is simple: a clean, fresh wax job beats a gritty one.

Salt and water. Salt water dries the skin and weakens its protective barrier. A UAB dermatologist notes that salt water can cause drying and irritant contact dermatitis or aggravate an existing skin condition. The same source points out that true water allergies are rare and that most swim-related skin problems are irritation.

Gear that fits badly. Old neoprene, sandy suits, cheap seams and loose fits all create friction points. Sandy gear peeling against skin is a common culprit, and poorly fitted suits and thin boardshorts are on the usual list.

Skin that is not used to it yet. Surfers who get in the water several times a week tend to build up tougher skin, while weekend surfers often get rash every time they paddle out, according to a surf skincare maker interviewed by Surf Science. The same source says rash does not mean you are doing something wrong. Body shape and skin sensitivity play a part. If you are on vacation and surfing for a few days, plan for protection from the first session rather than waiting for the first sore spot.

Wear the right layer

Start with a rash guard

A rash guard is the single easiest piece of prevention. It is flexible, repels moisture, protects against UV and prevents chafing through its snug fit. It creates a smooth barrier between your skin and a waxed board.

Fit matters more than brand:

• Choose snug, not tight. It should stay in place when you reach overhead, with no bunching under the arms.
• Pick flat or soft seams. Raised stitching along the ribs or underarm is where a rash guard starts to cause its own rash.
• Wear it directly on skin under a wetsuit, with nothing beneath it.
• Rinse it after every session. Sand trapped in the fabric defeats the purpose.

Sun protection is a bonus. The American Orthopaedic Society for Sports Medicine recommends rash guard coverage along with zinc and titanium sunscreen at SPF 30 on exposed skin, reapplied every 2 hours. We cover that in more detail in our sun protection guide for surfers.

Match the layer to water temperature

The same AOSSM resource gives a temperature chart: a rash guard is enough in 80 to 74 degree Fahrenheit water, a 2mm top or springsuit suits 73 to 66 degrees, and thicker suits follow as water gets colder. Use it as a starting point and check the current water temperature before you go. Warm-water spots like Waikiki often call for just a rash guard and shorts, and that is exactly why the rash guard fit matters so much: it is the only thing between you and the board.

Pick shorts that will not chew your thighs

Boardshorts with coarse seams or loose, long legs rub your inner thighs as you straddle the board. Look for soft, flat inseam stitching and a length that does not bunch when you sit up. For kids, the same logic applies, and our kids wetsuit fitting guide shows how a good fit keeps skin from rubbing in the first place.

Use balm on the hot spots

A rash guard covers most of your torso, but arms, neck, thighs and ankles still need help. This is where an anti-chafe balm earns its place. REI’s expert advice says that products made to lubricate high-friction areas can be used to pretreat known problem spots or fix hot spots mid-activity, applied liberally anywhere something rubs.

How to use it well:

1. Apply to clean, dry skin before you get in the water, since balm sticks better before it is wet.
2. Cover armpits, neck, inner thighs, wrists, ankles and the edge of any seam or collar. Wetsuit-focused guidance lists armpits, neck, wrists, thighs and ankles.
3. Choose a balm labeled for use with neoprene. Greasy products can break down wetsuit material, so check the label before you put anything on a suit you own.
4. Reapply if you take a break on the beach. Thick, greasy layers wear off in the water faster than you expect, so a quick touch-up between sessions is worth it.

Balm does not replace a rash guard on your ribs and chest. Think of it as the finishing layer for the places fabric cannot cover.

Technique and board habits that reduce friction

Gear is half the picture. How you move matters too.

• Keep your body centered and your chest lifted. Dragging your belly flat on the deck while paddling increases rubbing. A good paddling position lifts your chest slightly and keeps your arms moving cleanly past your ribs. Our paddling technique breakdown walks through the four stroke phases.
• Wax thoughtfully. Put wax where your feet and hands need it. Scrape off old, dirty wax and re-apply instead of stacking sandy layers. Wax made mainly of paraffin or beeswax can itself irritate the stomach, chest and inner thighs that touch the board, which is another reason to wear a rash guard.
• Keep sand out. Set your board on the sand deck-up or on a towel, and brush off your legs and belly before paddling out.
• Build tolerance gradually. Shorter first sessions with a rash guard on let your skin adapt.
• Warm up and stretch afterward. It does not prevent rash directly, but looser shoulders and hips mean smoother paddling and sitting. Try our 10-minute post-surf routine.

For a wider look at keeping a first session safe, see our beginner guide to preventing surfing injuries.

Care for your gear between sessions

A dirty wetsuit or rash guard is a rash waiting to happen. Salt, sand and bacteria build up in the fabric.

• Rinse in cool, fresh water after every session, inside and out.
• Hang the suit inside out in the shade, on a wide-shoulder hanger, rather than a thin wire one.
• Skip hot water. It can damage neoprene fibers.
• Avoid direct sun for drying, because UV can make neoprene brittle and less stretchy.
• Never stash a damp suit in a closed bag or a hot car trunk.

If you are renting gear, the same logic applies to you. Rinse yourself off as soon as you finish, and let rental gear dry on its own at the shop.

If you already have a rash

Prevention is the goal, but scrapes happen. Here is a careful approach.

Clean it first. Rinse off salt, sand and surface bacteria in a fresh water shower as soon as you can. A single ocean dip can swap your normal skin bacteria for ocean bacteria for about a day, which can matter if you have open sores from surf rash. Use a gentle, fragrance-free cleanser and lukewarm water. The UAB dermatologist advises avoiding lactic, salicylic and glycolic acids on irritated skin and following the shower with a thick, bland, fragrance-free moisturizer.

Let it breathe. Loose, soft clothing and uncovered skin when possible help healing. The clinical guidance describes surf rider’s dermatitis as typically resolving by itself, with supportive care like pain relief, protective dressings and soft clothing.

Give it a few days off the board. Surfing on raw skin reopens the wound. Use the time to rehearse your paddling on land or take a different kind of lesson.

When to see a health care provider

Contact a provider if a scrape looks infected, with warmth, red streaks, pus or fever, is very large, has deep debris in it, or you have not had a tetanus shot in 10 years. The American Academy of Dermatology adds that a rash needs medical attention if it blisters, turns into open sores, spreads rapidly or is painful, and that signs of infection include yellow or golden crusts, swelling, warmth or an unpleasant smell. If a rash comes with trouble breathing or swallowing, or swelling of the eyes or lips, seek emergency care immediately.

If redness, burning, persistent itching or stinging continues after rinsing and moisturizing, the UAB dermatologist recommends seeing a dermatologist.

Our perspective on surf rash

Most beginners think rash is the price of learning to surf. We see it differently: it is a sign that something in the setup is off, and the setup is easy to fix.

After more than 30 years of teaching in Waikiki, we have seen the same first-lesson mistakes: dragging the belly flat, sitting on a gritty deck, wearing something loose that bunches. Our instructors are experienced local and professional surfers, and they work on body position from the first minute because good paddling form is also the best friction control. A lifted chest and clean strokes mean less skin on the board.

That is also why we like to teach in small groups or private sessions when a beginner is nervous or has sensitive skin. One-on-one attention means someone is watching how you lie on the board and can adjust you before the rubbing starts. All the equipment is included in our lessons, so you can focus on your first waves rather than gear logistics.

Our advice is simple. Wear a snug rash guard, put balm on the spots it does not cover, rinse right away, and tell your instructor if anything starts to sting. A comfortable first session is the one that gets you back in the water the next day.

Johann

Ready to get in the water comfortably?

If you are planning your first session in Hawaii, a lesson is the quickest way to learn the body position that keeps rash away. Our group lessons cost $100 per person, semi-private lessons are $150 per person and private lessons are $180 per person. On the North Shore, group surf lessons start from $95 and private lessons from $145, with details on our services page.

Surfing several days in a row? Our multi-day guided packages are $472 for three days and $744 for five days, which gives your skin time to adapt while your technique improves. If you would rather practice on your own after a lesson, a Waikiki surfboard rental is $60 per day.

FAQ

Does a rash guard really prevent surf rash?

It is the most effective first step for most people. A rash guard puts a smooth, snug layer between your skin and the waxed board, which cuts down on friction. It also adds UV protection. Fit is key, so avoid loose styles and raised seams.

Can I use petroleum jelly or balm before surfing?

A thin layer of lubricant can reduce rubbing on skin, but it wears off in the water, so reapply between sessions. If you wear a wetsuit, pick a product labeled as safe for neoprene, since greasy products can harm the material. Always apply to clean, dry skin.

Is surf rash contagious?

No. It is a physical reaction to friction between skin and wet surf equipment, not an infection. However, an open scrape can become infected, so wash it and watch for warmth, pus, red streaks or fever.

How long does surf rash take to heal?

Mild irritation often settles by itself within days when you keep the area clean and avoid more friction. Deep scrapes take longer. If it is not improving, is painful, blistering or showing signs of infection, see a health care provider.

Will I get rash on a first surf lesson?

It is possible, especially if you wear loose clothing or lie flat on a gritty board, because beginner skin is not yet used to the friction. Wear a snug rash guard, use balm on the hot spots and ask your instructor to check your position.

Sources

• Honest Surf: Surf Rash, Causes, Treatment, Prevention
• SwimZip: What is a surf rash?
• IntechOpen: Aquatic sports dermatoses, clinical presentation and treatment guidelines
• ScienceDirect: Contact dermatitis in athletes
• Island Water Sports: Tips to Prevent Board Rash
• Body Glide: How to Treat and Prevent Wetsuit Rash
• UAB: How to protect skin and hair from chlorine and salt water
• Surf Science: How to Beat Board Rash
• Kalon Dermatology: What Is a Rash Guard?
• AOSSM: Preventing Surfing Injuries
• REI Expert Advice: Managing Chafing
• Quiksilver: How To Wash, Clean and Care for Your Wetsuit
• Cleanline Surf: Wetsuit Care Guide
• Swim2000: Men’s Wetsuit Buyer’s Guide
• Slipins: How Can You Prevent Surf Rash?
• MedlinePlus: Scrape
• American Academy of Dermatology: Rash 101 in adults

Recommended

• How to Prevent Surfing Injuries: A Beginner’s Safety Guide
• Sun Protection for Surfing: Your Complete Skin Safety Guide
• Apply Sunscreen 15 Minutes Early for Waikiki Surf Lessons