Customs & Etiquette
Onsen etiquette
温泉おんせんonsenWash first, soak second: the logic of the shared bath
In a Japanese onsen (hot spring) or sentō (public bath), bathers wash thoroughly at a shower station before entering the shared bath, bathe without swimwear, and keep towels and hair out of the water. The rules exist to keep water that many people share clean and calm.
Japan sits on one of the world's most volcanically active zones, and thousands of hot springs rise across the archipelago. Bathing in them is one of the country's most loved pastimes, from the great resort towns of Beppu and Kusatsu to modest village baths and the ryokan (traditional inn) with its own spring.
The shared bath works because everyone follows the same few rules. None is arbitrary: the bath water is for soaking, not washing, and it is shared by strangers who expect it to be clean and quiet. Once that principle is clear, onsen etiquette is easy.
Step by step
- 1Undress in the changing roomRemove shoes at the entrance, then in the changing room place all clothes in a basket or locker. Take only a small towel into the bathing area.
- 2Wash thoroughlySit on a stool at a shower station and wash your whole body and hair with soap. Rinse off completely and rinse the stool when you have finished.
- 3Enter the bath slowlyPour some bath water over yourself first (kakeyu) to adjust to the heat, then lower yourself in slowly. Keep the towel out of the water.
- 4Soak quietlyRelax without swimming or splashing and keep conversation low. Get out and cool down whenever you feel too hot.
- 5Dry off before the changing roomWipe yourself down with the small towel before stepping back into the changing area so the floor stays dry. Many people do not rinse off mineral-rich water afterwards.
What counts as an onsen
Legally, an onsen is water or gas from underground that either emerges at 25 °C or more or contains specified amounts of minerals, as defined by the Hot Springs Act of 1948. Many springs are rich in sulphur, iron, salt or carbonate, and bath houses post a notice describing the water's composition and traditional uses.
A sentō is a neighbourhood public bath with heated tap water, historically essential in cities where homes had no bath. The etiquette is the same in both, and in rotenburo (open-air baths) as well.
Rotenburo
露天風呂rotenburoAn open-air bath, often set among rocks with views of a river, sea or mountains.
Sentō
銭湯sentōUrban public bath, often with a painted mural of Mount Fuji above the tubs.
Kashikiri-buro
貸切風呂kashikiri-buroA private bath reserved for a set time, offered by many inns; suitable for families or those who prefer privacy.
Ashiyu
足湯ashiyuA footbath, often free and outdoors in spa towns; no undressing needed.
Why the rules exist
Traditional bathing separates cleaning from soaking. The body is washed outside the tub, and the tub is entered clean to relax. Soap, shampoo and dirt in the shared water would spoil it for everyone else, and in many onsen the water flows continuously from the source rather than being chemically treated, so keeping it clean depends on the bathers.
Nudity is simply the normal way of bathing and carries no special meaning. Swimwear is considered unhygienic because it is worn elsewhere, and hides whether a person has washed. Quiet behaviour follows from the bath's purpose as a place of rest.
Towels, hair and the water
Bathers take a small towel into the bathing area for washing and modesty, but it must never go into the bath water. People fold it on their head or leave it at the edge. Long hair is tied up so that it does not touch the water.
Swimming, splashing, diving and dunking the head are not done. Staying too long in hot water can cause dizziness; it is sensible to enter slowly, sit out on the edge when needed and drink water afterwards. Bathing after drinking alcohol is discouraged.
Tattoos
Many onsen and sentō have traditionally refused entry to people with tattoos, a rule rooted in the association of full-body tattoos with organised crime. Practice varies widely: some baths welcome tattoos, some allow them if covered with a skin-coloured patch, and some still refuse. Private baths avoid the question entirely.
Policies change and are set by each facility, so it is best to check the bath's own website or ask before visiting.
Mixed bathing
Most baths are separated by sex, with the entrances marked by noren curtains, typically blue or reading 男 for men and red or reading 女 for women. The two sides are sometimes swapped between morning and evening in inns, so it is worth checking the sign each time.
Konyoku, mixed bathing, survives in some rural hot springs. Some now permit bathing wraps or towels, but rules depend on the individual bath.
Frequently asked questions
Do you have to be naked in an onsen?
Yes, in almost all traditional onsen and sentō bathers are naked. Swimwear is only worn in some mixed leisure spas that explicitly allow it.
Can I use an onsen if I have tattoos?
It depends on the facility. Some accept tattoos, some allow them if covered, others refuse; private baths are an option. Check with the bath before visiting.
Why can't the towel go into the water?
The towel has been used for washing, and the bath water is shared. Keeping it out of the water keeps the bath clean for others.
Should I shower after an onsen?
It is not required. Many people deliberately leave the mineral water on their skin, but those with sensitive skin may prefer to rinse off acidic or sulphurous water.
Are onsen safe for everyone?
Most healthy people bathe without problems, but those with heart conditions, high blood pressure or pregnancy should take care with hot water and seek medical advice. Avoid bathing after alcohol.
Related
Sources
- 1.温泉の保護と利用 (opens in a new tab) — 環境省 (Ministry of the Environment)
- 2.Japan National Tourism Organization – Official travel guide (opens in a new tab) — JNTO