10 Unwritten Japanese Onsen Rules All Travellers Should Know

Being highly volcanic, Japan has thousands of onsen (hot springs) all across the archipelago. To be classed as an onsen, an establishment’s water must contain at least one of 19 minerals, such as iron, sulphur or hydrogen carbonate, and be naturally warmer than 25 degrees Celsius. According to the Nippon Onsen Research Association, there are more than 3000 onsens in Japan. 

There are several different ways to experience an onsen. Many ryokan (traditional Japanese inns) are built on top of hot springs and have baths fed with onsen water. This is a great introductory experience: you can bath at your leisure, travelling between your room and the baths in a yukata (light cotton kimono, provided by inns to wear in-house). At some fancier ryokan you will have the option to upgrade to a room with its own private onsen bath.

A soak in an onsen is a must-do experience in Japan, that comes with several unwritten rules:

Wrap the yakata properly

If you decide to wear a yukata to walk to the onsen, which is highly encouraged, put the left side of the garment over the right.

Shower first

After you exit the change rooms you will find showers closer to the onsen baths. 

Tie up your hair

Before you enter the onsen, tie up your hair to ensure it doesn’t get in the bath.

Go alone or in small groups

Big groups of foreigners tend to draw attention and are often considered to be a bit intimidating.

Keep your voices soft and quiet

The onsen is a place to relax. You should try to be quiet and calm.

Place your shoes in the line

Before you enter the onsen you will notice a line of shoes. The Japanese line their shoes up facing away from the onsen so they are easy to put on when they exit.

You must be naked

Keep in mind that everyone is naked. This is all part of the experience. Go with it.

Take the small towel with you

Japanese people often place the towel on their head when they bathe. This helps to cool down the head while enjoying the heat on the rest of the body.

Give people space

It is common courtesy to give other people some space and not sit down right next to them, or squeeze into an already well-filled pool.

Short eye contact

If you do want to interact with the locals, follow the Japanese onsen etiquette and make (very) short eye contact and smile.

Go slow

The onsen is not a swimming pool. It’s not a place to splash and play.

There are also onsen in the wild. Hidden in the mountains or along undeveloped coasts, these humble baths may be no more than a pool in a riverbed blocked off with stones or a tidal basin beside crashing waves. Bathing is open-air, often co-ed and usually free. Hokkaidō, in particular, has some good ones, as do some of Japan’s more far-flung islands. In many of these, it’s okay to wear a swimsuit.