Quick answer: The safest, simplest choice for what to wear in a sauna is a clean towel — one to sit on, one to dry off with. If the venue requires more, go for a swimsuit or lightweight shorts in a natural fibre like cotton. Avoid synthetic fabrics, metal jewellery, and anything you'd normally wear to the gym. Keep it minimal, keep it clean.
First time in a sauna? You're probably picturing yourself walking in, glancing around, and quietly panicking because you've no idea what everyone else is wearing — or not wearing. It happens to everyone.
The truth is, there's no single universal rule. What's appropriate depends on where you are: a hotel spa has different expectations to a private home sauna, and a traditional Finnish wood-burning setup plays by different rules again. But across all of them, the principles are the same — comfort, hygiene, and a bit of common sense.
This guide covers sauna etiquette and what to wear for men and women, what to wear in an infrared sauna, why your polyester gym kit deserves to stay in your bag, and a quick checklist so you're not caught short.
The short answer: the safest, simplest sauna attire options
If you're unsure and want a default, here it is:
- A towel to sit on — always, regardless of venue
- A second towel to cover up — as needed, or to dry off after
- Swimwear if the venue requires it — more on venue rules below
- Nothing underneath (in private settings or traditional saunas) — perfectly normal, just always keep that towel barrier between you and the bench
Leave behind anything with metal fastenings, zip pulls, or wire. A full tracksuit. Your gym shoes. These aren't just uncomfortable — some can genuinely become a hazard when the heat's cranked up.
Sauna etiquette: what to wear (and what not to do)
Sauna etiquette around what to wear comes down to a few non-negotiables that apply almost everywhere:
- Always sit on a towel. This is hygiene basics — the bench doesn't need your sweat directly on it, and your skin doesn't need to absorb whatever's been left behind by someone else.
- Shower first. Before you go in, not after. Fragrance, fake tan, or suncream on the skin doesn't belong in a sauna.
- Keep it simple. Bulky layers, dye-heavy fabrics, and anything tight or restrictive will just make you miserable in the heat.
- Remove jewellery. Rings, necklaces, watches, and metal hair clips heat up quickly and can cause burns. Take them off before you go in.
- Check the signage. House rules at the venue always take priority. If the wall says swimwear required, swimwear it is.
- Tie long hair up. And consider a small towel over your head or shoulders to manage sweat — a sauna hat (the traditional linen or wool kind) is also a perfectly legitimate option and actually helps protect your head from intense overhead heat.
What to wear in a sauna for women
For women, the most practical choices are a swimsuit, bikini, or a towel wrap, depending on what the venue allows. A simple swimsuit, bathing suit, or bikini in loose fitting cuts and breathable materials — cotton where possible — is usually the most comfortable option. Avoid underwire bras (the heat and pressure combination isn't kind to either you or the fabric), though a sports bra can work if it's non-metallic and venue-appropriate, and steer clear of tight elastics, which can leave marks when your skin is hot and swollen.
If you're in a private sauna at home or in a more relaxed traditional setting, many women prefer just a towel. That works perfectly well — just make sure it's a full-sized one.
A few extras worth packing: a dry change of underwear and clothes for after, and flip-flops or sliders for the changing area.
What to wear in a sauna for men
For men, men wear swim shorts, a cotton towel, or lightweight shorts in a natural fibre where the venue permits. The best clothing is loose, lightweight sauna wear in natural fibres, since fit matters more than you'd think and anything tight or compressive becomes genuinely unpleasant once the temperature climbs.
Avoid compression leggings, thick waistbands, or anything with zips or metal detailing. Board shorts with a drawstring? Good. Anything from your gym kit? Probably not — and we'll get to why in a moment.
What to wear in an infrared sauna (it's a bit different)
Infrared saunas work differently to traditional steam saunas. Rather than heating the air around you, they use infrared light to warm the body directly — which means you'll still sweat significantly during an infrared sauna session, but the ambient temperature feels lower and the experience is less intense.
Because of the way infrared heat penetrates the body, many people actually prefer less fabric during infrared sessions — the more skin is exposed, the more effectively the heat does its job and helps with body temperature regulation. A towel or minimal natural-fibre clothing is the usual recommendation.
As always, follow the specific guidance from your venue or the manufacturer of your home unit, particularly around bench coverings and hygiene, and focus on staying hydrated by drinking water before and after.
The polyester problem: why your synthetic kit should stay in your bag
Here's something that doesn't get talked about enough. Most gym wear, swimwear, and activewear is made from synthetic fabrics — polyester, nylon, spandex — and while these materials are perfectly fine for a run or a workout, they're not well suited to sauna use.
The most immediate issue is comfort: synthetics trap heat and moisture against the skin. In everyday exercise that's manageable, but in a sauna where you're already hot and sweating heavily, it can make you feel clammy and uncomfortable rather than relaxed.
There's also a growing body of evidence around the broader risks. Research shows that sweating increases the skin's permeability, which means that when synthetic fabrics — which can contain chemical additives including phthalates and PFAS ("forever chemicals") — are pressed against warm, sweaty skin, the rate of absorption increases. According to a 2024 study published in Environment International, dermal absorption of microplastics and associated chemicals rises significantly when the skin is moist or warm. Saunas create exactly those conditions.
This doesn't mean you need to panic about every gym session, but in the sauna specifically — where the whole point is to support your body — it makes sense to avoid creating unnecessary exposure. Around 70% of global textile production is now synthetic, according to research published in Resources, Conservation and Recycling (2025), up from roughly 30% in the 1980s, so it's worth being intentional about when and where you wear these fabrics.
Safer alternatives:
- 100% cotton — breathable, soft, and widely available
- Linen — light and airy, ideal for lounging rather than heavy sweating
- Merino wool (lightweight) — naturally odour-resistant if you prefer a little more coverage
- A plain towel — genuinely, still the best option of all
If in doubt, go natural, go minimal, and bring a clean towel.
Your sauna bag: a quick packing checklist
- ✅ 2 towels (one to sit on, one to dry off with)
- ✅ Water bottle — for staying hydrated before, during, and after a sauna session
- ✅ Flip-flops or sliders for changing areas
- ✅ Small toiletry kit (gentle cleanser, deodorant for after, hair tie)
- ✅ Dry change of clothes, including cosy layers
- ✅ Optional: a robe for walking to and from the sauna, especially if you’re pairing it with a cold plunge or cold water recovery
Frequently asked questions
Can I wear gym clothes in a sauna?
It's not recommended. Most gym clothes are synthetic fabrics that trap heat and sweat, making the experience uncomfortable. In high temperatures, synthetic materials can also increase your skin's exposure to the chemical additives they contain. For appropriate attire, natural fibres or a towel are a much better option.
Should I wear underwear in a sauna?
In most cases, no. Underwear is often synthetic, tight, and uncomfortable in the heat. If you're in a venue that requires coverage, opt for a clean swimsuit or towel instead.
Can I wear just a towel?
Absolutely. In many traditional settings and home saunas, a towel is the preferred option for both comfort and hygiene. Going sauna naked is also a common practice in many traditional settings, but you should still use a towel to sit on regardless of what else you're wearing.
Are sauna hats actually necessary?
Not strictly necessary, but they do serve a practical purpose — they protect your head and ears from intense overhead heat, which can help you stay in longer without discomfort. In a dry sauna, a sauna cap can also help protect hair from drying out. Traditional versions are made from linen or merino wool.
Can I wear jewellery in a sauna?
No. Metal heats up quickly and can cause burns. Remove rings, necklaces, watches, and metal hair accessories before going in.
What should I wear in a mixed sauna?
Follow the venue's rules first and foremost. In public saunas and other shared spaces, venues often set a clear dress code with specific rules on coverage and footwear. In most UK public or spa settings, a swimsuit or towel is expected. In many cultures, going nude is accepted, but this varies by venue, and ignoring local norms can be considered rude. In more traditional or private settings, the norm may differ — when in doubt, wrap up and check.
Ready to make the most of your sauna sessions?
Getting the basics right — natural fabrics, a clean towel, no metal, and a quick shower beforehand — means you can focus on what the sauna is actually there for: genuine recovery, better sleep, and a bit of proper downtime.
At Vitru, we believe that investing in how you feel is one of the most worthwhile things you can do. If this has got you thinking about setting up a proper recovery space at home, take a look at our sauna collection — from outdoor pods and barrel saunas to premium cedar cabins built for serious, repeatable sessions.