What to Wear in a Sauna: Towel, Shorts, Briefs or Nothing?

What to wear in a sauna depends on where the sauna is. At home, many people wear a towel or nothing at all. At a gym or spa, sit on a towel and wear swim shorts or a swimsuit if the rules ask for it. Either way, pick natural fabrics, take off anything metal and follow the posted rules.

If you also want to keep the testes cooler during your session, cooling underwear worn beneath your towel is a simple add-on.

Want cooling built into what you wear? See how SaunaArmor cooling briefs work.

What should you wear in a sauna?

There is no single answer, because sauna customs vary by country, facility and even time of day. These three situations cover most cases.

At home or in a private sauna

You decide. Many people sit on a towel and wear nothing else, which is the traditional approach in Finland. Others prefer cotton shorts or swim shorts. The one rule that holds everywhere is a towel between your skin and the bench, both for hygiene and because the wood gets hot.

At a gym or spa sauna

Most gyms and spas require a towel and often swimwear or shorts. Check the sign on the door or ask staff, because the rules differ. When in doubt, wear swim shorts or a swimsuit and bring two towels: one to sit on and one to dry off.

At a public or mixed sauna abroad

In some countries, nudity is normal in designated saunas and swimwear is banned for hygiene reasons. In others, it is the reverse. Look for the posted rules before you go in, and follow what other regulars are doing.

Which fabrics work best in a sauna?

Choose fabrics that breathe and feel fine when damp. Cotton, linen and wool felt are all traditional choices. Skip anything that traps heat against your skin or that you cannot easily wash.

A towel is the one item that works everywhere. Bring two if you can, so you never sit in your own sweat on the way out.

What should you not wear in a sauna?

Some items are uncomfortable, some are unsafe and some are against the rules. Leave these outside:

• Metal jewelry and watches, because metal heats up quickly and can burn your skin.
• Glasses, because the frames get hot against your face.
• Synthetic clothing, which can trap heat and feel unpleasant once it is soaked.
• Tight or heavy clothing, which restricts airflow and makes you hotter.
• Phones and electronics, which can overheat and are often banned for privacy.

What to wear in a sauna if you want to protect your fertility

The testes sit outside the body so they can stay about 2–4°C cooler than your core. A traditional sauna typically runs at around 66–91°C (150–195°F), so the air is far hotter than your body and that cooling gap shrinks.

In a 2013 University of Padova study, men who used a sauna for 15 minutes twice a week for three months had lower sperm count and motility. The effect reversed, but only months after they stopped. No study has yet tested cooling underwear on sperm outcomes, so treat cooling as a practical way to reduce heat, not a guarantee.

That makes underwear the one clothing choice with a real job to do in a sauna. Cooling during the session reduces heat at the source. A cold plunge afterward cannot undo exposure that already happened.

Sauna shorts with an ice pack: what to look for

Many men search for "sauna shorts with ice pack" or "sauna underwear with ice pack". Whatever the name, look for four things:

• A closed pouch that holds the pack in place.
• A fabric barrier between the cold and your skin.
• At least two inserts, so one can refreeze while you use the other.
• A breathable cotton body.

A loose pack tucked into regular shorts slides out of position and drips onto the bench.

How to wear cooling briefs in a sauna

SaunaArmor cooling briefs have a 100% cotton body and a horizontal zip pouch that holds a reusable insert beneath the testes. Wear them under your towel like normal underwear:

1. Freeze one insert for 1–2 hours before your session.
2. Zip it into the pouch.
3. Put the briefs on and wrap your towel over them.
4. Sit on a lower or middle bench and use the sauna as usual.

Each pair comes with two inserts, so one can be in the freezer while you use the other. Check the size chart: the cotton body has minimal stretch, so size up if you are between sizes or have larger legs.

What to wear in a sauna: infrared vs traditional

The clothing rules are the same, but the heat is not. Traditional saunas typically run at around 66–91°C (150–195°F), while infrared saunas run cooler at the air level, roughly 43–57°C (110–135°F). In an infrared sauna you may find lighter clothing or a towel is enough, and sessions often feel less intense.

Whichever you use, shorter sessions are easier on your body while you are learning your limits. See our guide on how much time to spend in the sauna.

Sauna etiquette checklist

Good etiquette is mostly about hygiene and respect for other people. These habits cover it:

1. Shower before you go in.
2. Sit and lie on a towel, always.
3. Keep your phone outside.
4. Keep conversation quiet, and do not stare.
5. Leave if you feel dizzy or unwell, and drink water afterward.
6. Follow the posted rules, even if they differ from what you are used to.

What to pack in your sauna bag

A small, well-packed bag makes every session easier:

• Two towels, one to sit on and one to dry off.
• Flip-flops for the floor.
• A water bottle.
• A felt sauna hat to insulate your head from the hottest air.
• A wool sauna mat if you want a cleaner, more comfortable seat.
• The insulated travel case if your inserts need to stay frozen on the way, since it holds up to eight and keeps them frozen for up to four hours.

How to stay comfortable once you are in the sauna

What you wear is only part of a good session. A few habits keep you comfortable and make it easier to judge how you feel.

• Start on a lower bench and move up only if you feel fine, because the air is hotter higher up.
• Keep your first sessions short and build up gradually.
• Drink water before and after, and leave if you feel lightheaded.
• Cool down gradually afterward, and sit out for a few minutes if you feel unwell.

If something feels wrong, leave. No outfit or accessory is worth ignoring dizziness, a racing heart or nausea.

What to wear after the sauna

Dry off properly and change into dry, loose clothes, ideally cotton. Putting sweaty clothes back on can leave you chilly and uncomfortable. If you use cooling inserts, put them back in the freezer so they are ready for next time.

Frequently asked questions

Can you wear underwear in a sauna?

Yes, in most gyms and spas, and cotton is the best choice. In some traditional or single-sex saunas nudity is the norm, so check the rules. If you go without, still sit on a towel.

Can you wear a swimsuit in a sauna?

Often yes, and many gyms require it. Swim fabric is usually synthetic and can get hot against the skin, so keep sessions short and take it off if it feels uncomfortable. Some facilities ban swimwear for hygiene, so check first.

Is it okay to wear cotton shorts in a sauna?

Yes. Cotton breathes and is comfortable when damp. Choose a loose pair without metal zippers or snaps that could heat up.

Do you wear shoes in a sauna?

Not on the bench. Wear flip-flops or sandals to protect your feet on hot, wet floors, and leave them outside the hot room.

The bottom line on what to wear in a sauna

Keep it simple: a towel to sit on, natural fabrics, nothing metal and an eye on the house rules. If you sauna regularly and plan to have kids now or later, underwear is where you can make a real difference by cooling during the session instead of after it.

Sauna Protocol makes gear for men who sauna regularly. Learn why we started or browse the full range.

Shop SaunaArmor cooling briefs

This article is for general information only and is not medical advice. If you have concerns about your fertility or your health, speak with a doctor.