What to Wear in a Sauna? (Dos, Don'ts and Pro Tips)

The short answer: as little as possible, made from natural fibres. In a traditional Finnish sauna running at 80–100°C, your attire directly affects your comfort, your safety, and how well your body thermoregulates. Synthetic fabrics trap heat, restrict sweat evaporation, and at those temperatures, some release chemicals you do not want on your skin.

Whether you're stepping into a private home sauna or a shared public one, the same rules apply. Natural fibres or nothing. Loose fit. No metal. No synthetics. Here's exactly what that looks like in practice.

What to Wear in the Sauna

The right attire is not about aesthetics. It's about keeping your body free to sweat, your skin free to breathe, and your session free from anything that shouldn't be in a 90°C environment.

The reason we built a sauna with no glue is the same reason to be picky about what you wear in a sauna. Whatever is inside the sauna is being heated to high temperatures, this means most polyester (aka plastic) activewear is a no no.

Here are the options that actually work.

Go Naked

This is the Finnish standard — and Finland invented the sauna, so it carries weight. Nudity in both private and public saunas is common practice in Finland, as documented by the Finnish Sauna Society. No fabric means nothing between your skin and the heat. Maximum sweat. Maximum thermoregulation.

If you're in a private home sauna, this is the most effective option. If you're in a shared setting, check the rules and your own comfort level first.

Cover Yourself with a Towel

A towel is the universal sauna solution. Wrap it around your waist or chest, lay it on the bench beneath you, or both. Cotton or linen — nothing synthetic.

At public saunas, towels are typically provided. In your home sauna, have one on hand regardless of what else you're wearing. The bench will thank you.

Wear Cotton Clothing

If you prefer more coverage, cotton is the gold standard. It's breathable, it allows sweat to escape, and it does not trap heat against your skin the way synthetics do. Loose-fitting, light-coloured, and clean — those are the three requirements.

According to the National Institute of Environmental Health Sciences, synthetic fabrics like nylon and polyester trap heat and moisture against the skin, increasing discomfort and interfering with the body's natural cooling response. Cotton does the opposite.

One rule that applies regardless: your clothing must be clean. The sauna is a place to purge toxins — not redistribute them.

Sauna Hats

Your head heats up faster than the rest of your body in a sauna. That temperature differential is why experienced sauna users get dizzy — the brain overheats before the body signals you to leave. A sauna hat slows that process down.

Wool felt is the traditional material. It insulates your head from the direct radiant heat without trapping it. If you sauna frequently, a hat is worth the investment. Just make sure it's made from natural fibres — wool or cotton, not synthetic blends.

Footwear

Not essential in a private home sauna, but useful in shared public settings. Flip flops or sauna sandals protect your feet from the floor and reduce slip risk. Rubber soles handle the heat without issue.

Style points? Absolutely. Mandatory? No.

What Not to Wear in the Sauna

What you leave outside matters as much as what you bring in. The wrong attire can restrict circulation, release chemicals at high temperatures, and undermine the entire point of the session.

Steer Clear of Synthetic Fibres

Polyester, nylon, PVC — none of these belong in a sauna. At 80–100°C, synthetic fabrics trap sweat against your skin, restrict evaporation, and some release chemical compounds when heated. If you're wearing a standard gym kit or compression gear, leave it at the door.

You are in the sauna to detoxify. Not to re-toxify.

Choose Your Swimwear Wisely

Swimwear is acceptable — but the fit and construction matter. Tight-fitting swimwear compresses the skin and restricts blood flow as your vessels dilate in the heat. That's uncomfortable and counterproductive.

More importantly: go wire-free. Metal heats rapidly in a sauna environment and can cause burns. A soft, wire-free cotton swim top or sports bra is the right call. And again — nothing synthetic.

Don't Wear Makeup

Harvard Health research shows that sauna heat opens pores and drives increased sweating — one of the mechanisms behind the skin-clearing effects of regular sauna use. Makeup clogs those open pores, blocking the process entirely.

Go in clean. Come out cleaner. That is the protocol.

Avoid Strong Perfumes

In a confined heated space, a heavy fragrance becomes overwhelming. It disrupts the session for everyone present and clashes with the natural timber environment of the sauna itself.

Essential oils diffused into the ölöy steam are a different matter — cedar, eucalyptus, and birch are all traditional and on-brand. Synthetic body spray is not.

Why Fabric Choice Matters More Than You Think

Most people treat sauna attire as an afterthought. It is not.

At 90°C, your body is working hard to push sweat to the surface, dilate blood vessels, and regulate core temperature. Every layer of clothing either assists or interferes with that process. Natural fabrics — cotton, linen, wool — assist. Synthetics interfere.

Natural Fabrics

Cotton and linen are breathable and wick moisture away from the skin rather than trapping it. They allow sweat to evaporate, which is how your body dissipates heat. In a sauna running at 80–100°C, that evaporation mechanism is critical.

If you prefer swimwear, choose pieces without metal fasteners or embellishments. Metal heats fast in a high-temperature environment and direct contact with hot metal on skin causes burns.

Synthetic Fabrics

Nylon, polyester, and PVC create a barrier between your skin and the air. Sweat accumulates. Temperature regulation suffers. And at sustained high heat, some synthetic materials release compounds that you absolutely do not want to be inhaling in an enclosed space.

The whole point of a quality sauna session is to purge what your body does not need. Synthetic clothing works against that from the first minute.

For a deeper look at how the sauna environment itself should be engineered — and why zero-toxin construction matters as much as what you wear — read our guide to sauna temperature and what it means for your session.

Frequently Asked Questions

What are you supposed to wear in a sauna?

Natural fibres or nothing. Cotton, linen, and wool are all appropriate. Loose-fitting, clean, and wire-free. A towel is the baseline — either worn or laid on the bench beneath you. Synthetic fabrics, tight clothing, and anything with metal fasteners should be left outside.

Can you wear a bathing suit in a sauna?

Yes, but choose carefully. A loose-fitting, wire-free swimsuit in a natural or at minimum non-PVC fabric is acceptable. Avoid tight compression swimwear, as it restricts circulation when blood vessels dilate in the heat. Always bring a towel to sit on regardless of what you are wearing.

What should you not wear in a sauna?

Avoid synthetic fabrics including polyester, nylon, and PVC. Avoid tight-fitting clothing and anything with metal components — underwire bras, metal buckles, or jewellery. Do not wear makeup or strong synthetic perfumes. At 80–100°C, synthetics trap heat and some release chemical compounds.

What is sauna etiquette in Australia?

In private home saunas, personal preference governs. In shared or public settings: arrive clean, sit on a towel, avoid strong fragrances, keep noise down, and respect other users' space. In traditional Finnish sauna culture, nudity is standard — in Australian public settings, check the facility's rules first.

Can I take my phone into a sauna?

No. High heat and humidity will damage internal components and may cause the battery to overheat. Most phones are not rated for sustained exposure above 45°C. Leave it outside — the session is 15 to 20 minutes. It can wait.